This document discusses applying cell zooming to compensate for cell outages in mobile networks. Cell zooming involves adjusting transmission power levels or antenna heights to vary cell sizes. The document develops an algorithm using the Okumura-Hata propagation model to calculate the transmission power or antenna height needed for outage compensation. Simulation results using a planning software show that cell zooming can achieve outage compensation with minimal human intervention, in line with self-organizing network (SON) objectives.
Energy Efficient Wireless CommunicationsJingon Joung
The tutorial begins with a brief introduction of spectral efficiency (SE) and energy efficiency (EE) in communications. Various definitions of EE will also be covered briefly. One typically used EE, i.e., bits-per-Joule, is theoretically derived and the ideal SE-EE tradeoff is introduced. It is recognized that a power amplifier (PA) is one of the most critical components in wireless communication systems and consumes a significant fraction of the total energy. The fundamental properties of PA, such as linearity and efficiency, are introduced. With the practical characteristics of PA, the detrimental effects of the signal non-linearity and power inefficiency of the PA on the SE, EE, and their tradeoff, are quantified.
Next, various existing EE-improving techniques are categorized from three perspectives: PA design, signal design and network design. This broad understanding based on the three categories will help motivate holistic design approaches to mitigate the non-ideal effects in real-life PA devices, and accelerate cross-domain research to further enhance the available techniques for high EE or good SE-EE tradeoff.
Last, the remaining challenges and future work for EE issue will be discussed.
This document summarizes a presentation on analyzing massive MIMO systems under different wireless scenarios. It begins with background on mobile communication generations and challenges with exponentially growing data demand. It then discusses massive MIMO as a promising technology for 5G, noting it can support large numbers of users simultaneously and increase spectrum efficiency. However, challenges include hardware mismatch in TDD systems and highly correlated spatial gains. The presentation outlines analyzing the impact of these issues, as well as the feasibility of massive MIMO in cooperative networks. It proposes modeling hardware mismatch and deriving the probability distribution functions of amplitude and phase mismatches. It also discusses using different precoding techniques like zero-forcing to calculate signal-to-interference-plus-noise ratio in the down
Green technology is the development of products and systems that minimize environmental impact and conserve resources. It aims to reduce degradation of the environment, greenhouse gas emissions, and efficient use of energy and natural resources. Spectral efficiency refers to the information rate transmitted over a given bandwidth, while energy efficiency is the number of bits transmitted per joule of energy. Techniques like orthogonal frequency-division multiple access, multiple-input multiple-output, and relay transmission can improve the spectral efficiency of wireless networks. Adaptively allocating resources and turning off redundant systems when not in use can enhance both the energy efficiency and spectral efficiency-energy efficiency tradeoff.
Enabling full-duplex in multiple access technique for 5G wireless networks ov...TELKOMNIKA JOURNAL
This document analyzes the performance of a two-user non-orthogonal multiple access (NOMA) network where one user is served directly by the base station and the other is served via an unmanned aerial vehicle (UAV) relay operating in full-duplex mode. It derives the exact outage probabilities of the two users under Rician fading channels. The analysis provides guidelines for designing UAV-enabled wireless networks using NOMA techniques. Key results include the outage probabilities accounting for interference at both the UAV relay and users under different self-interference conditions at the relay.
This document discusses green communication and summarizes several research papers on the topic. It outlines the objectives of green communication as protecting the environment from harmful EM radiation, reducing greenhouse gases, and reducing wireless network operational costs. It then summarizes several papers on topics like power control, resource allocation, power allocation, and massive MIMO. The document also discusses energy consumption in the ICT industry, wireless resource trading challenges, and open research areas in green communication like massive MIMO and cooperative communication. It presents two case studies analyzing the energy efficiency of massive MIMO systems with considerations for aspects like channel gain, number of antennas, and transceiver power consumption.
Enhancement algorithm for reverse loop technique on planar reverse loop antennaTELKOMNIKA JOURNAL
This document presents a method to stabilize wireless transfer efficiency (WTE) between two planar loop antennas using a reverse loop technique. The method involves introducing a reverse loop to the transmitting planar loop antenna to form a planar reverse loop antenna (PRLA). This helps control the mutual inductance between the antennas in the over-coupled region where they are closer than the optimal operating distance. Mathematical modeling and electromagnetic simulations show that the PRLA maintains a more constant mutual inductance with distance changes compared to conventional planar loop antennas. Fabricated prototypes validate that the reverse loop technique results in greater stability of WTE at closer distances without additional system adjustments.
Massive MIMO for Cooperative Network ApplicationVARUN KUMAR
This document summarizes a research paper on analyzing the achievable rate and power efficiency of massive MIMO in cooperative networks using zero-forcing receivers. It outlines the problem definition, system model, and simulation results. The system model considers uplink transmission from mobile users to a base station via relay stations. It analyzes the observed signal-to-noise ratio in direct and cooperative transmission and defines achievable rate metrics for direct, non-cooperative, and cooperative decoding schemes. Power efficiency is defined as the achievable rate divided by the total transmit power of all nodes.
Survey of analysis and performance of ofdm signals in time and frequency disp...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Energy Efficient Wireless CommunicationsJingon Joung
The tutorial begins with a brief introduction of spectral efficiency (SE) and energy efficiency (EE) in communications. Various definitions of EE will also be covered briefly. One typically used EE, i.e., bits-per-Joule, is theoretically derived and the ideal SE-EE tradeoff is introduced. It is recognized that a power amplifier (PA) is one of the most critical components in wireless communication systems and consumes a significant fraction of the total energy. The fundamental properties of PA, such as linearity and efficiency, are introduced. With the practical characteristics of PA, the detrimental effects of the signal non-linearity and power inefficiency of the PA on the SE, EE, and their tradeoff, are quantified.
Next, various existing EE-improving techniques are categorized from three perspectives: PA design, signal design and network design. This broad understanding based on the three categories will help motivate holistic design approaches to mitigate the non-ideal effects in real-life PA devices, and accelerate cross-domain research to further enhance the available techniques for high EE or good SE-EE tradeoff.
Last, the remaining challenges and future work for EE issue will be discussed.
This document summarizes a presentation on analyzing massive MIMO systems under different wireless scenarios. It begins with background on mobile communication generations and challenges with exponentially growing data demand. It then discusses massive MIMO as a promising technology for 5G, noting it can support large numbers of users simultaneously and increase spectrum efficiency. However, challenges include hardware mismatch in TDD systems and highly correlated spatial gains. The presentation outlines analyzing the impact of these issues, as well as the feasibility of massive MIMO in cooperative networks. It proposes modeling hardware mismatch and deriving the probability distribution functions of amplitude and phase mismatches. It also discusses using different precoding techniques like zero-forcing to calculate signal-to-interference-plus-noise ratio in the down
Green technology is the development of products and systems that minimize environmental impact and conserve resources. It aims to reduce degradation of the environment, greenhouse gas emissions, and efficient use of energy and natural resources. Spectral efficiency refers to the information rate transmitted over a given bandwidth, while energy efficiency is the number of bits transmitted per joule of energy. Techniques like orthogonal frequency-division multiple access, multiple-input multiple-output, and relay transmission can improve the spectral efficiency of wireless networks. Adaptively allocating resources and turning off redundant systems when not in use can enhance both the energy efficiency and spectral efficiency-energy efficiency tradeoff.
Enabling full-duplex in multiple access technique for 5G wireless networks ov...TELKOMNIKA JOURNAL
This document analyzes the performance of a two-user non-orthogonal multiple access (NOMA) network where one user is served directly by the base station and the other is served via an unmanned aerial vehicle (UAV) relay operating in full-duplex mode. It derives the exact outage probabilities of the two users under Rician fading channels. The analysis provides guidelines for designing UAV-enabled wireless networks using NOMA techniques. Key results include the outage probabilities accounting for interference at both the UAV relay and users under different self-interference conditions at the relay.
This document discusses green communication and summarizes several research papers on the topic. It outlines the objectives of green communication as protecting the environment from harmful EM radiation, reducing greenhouse gases, and reducing wireless network operational costs. It then summarizes several papers on topics like power control, resource allocation, power allocation, and massive MIMO. The document also discusses energy consumption in the ICT industry, wireless resource trading challenges, and open research areas in green communication like massive MIMO and cooperative communication. It presents two case studies analyzing the energy efficiency of massive MIMO systems with considerations for aspects like channel gain, number of antennas, and transceiver power consumption.
Enhancement algorithm for reverse loop technique on planar reverse loop antennaTELKOMNIKA JOURNAL
This document presents a method to stabilize wireless transfer efficiency (WTE) between two planar loop antennas using a reverse loop technique. The method involves introducing a reverse loop to the transmitting planar loop antenna to form a planar reverse loop antenna (PRLA). This helps control the mutual inductance between the antennas in the over-coupled region where they are closer than the optimal operating distance. Mathematical modeling and electromagnetic simulations show that the PRLA maintains a more constant mutual inductance with distance changes compared to conventional planar loop antennas. Fabricated prototypes validate that the reverse loop technique results in greater stability of WTE at closer distances without additional system adjustments.
Massive MIMO for Cooperative Network ApplicationVARUN KUMAR
This document summarizes a research paper on analyzing the achievable rate and power efficiency of massive MIMO in cooperative networks using zero-forcing receivers. It outlines the problem definition, system model, and simulation results. The system model considers uplink transmission from mobile users to a base station via relay stations. It analyzes the observed signal-to-noise ratio in direct and cooperative transmission and defines achievable rate metrics for direct, non-cooperative, and cooperative decoding schemes. Power efficiency is defined as the achievable rate divided by the total transmit power of all nodes.
Survey of analysis and performance of ofdm signals in time and frequency disp...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Limitation of Maasive MIMO in Antenna CorrelationVARUN KUMAR
The document discusses the limitations of massive MIMO systems due to antenna correlation. It presents a system model to analyze the impact of antenna correlation on achievable rates and power efficiency. Simulation results show that antenna correlation significantly degrades performance compared to an uncorrelated channel. The document concludes that while massive MIMO provides diversity, antenna proximity causes correlation and coupling which cannot be solved by increasing antenna spacing alone under physical space constraints at the base station.
Simulation and optimization of a tuneable rectangular microstrip patch antenn...TELKOMNIKA JOURNAL
In this paper, a tuneable rectangular microstrip patch antenna (MPA) is simulated and optimized to operate in four frequency bands of the next generation of wireless communication systems. The proposed design incorporates a copper radiating patch with four implanted graphene strips for tuning purposes. The reconfigurable surface impedance of graphene can easily be altered by applying a DC voltage bias directly to the graphene strips, allowing the operating frequency of the antenna to be tuned as desired. The capability of the applied voltage to tune the operating frequency band of the proposed antenna is studied via computer simulation technology (CST) microwave studio (MWS). Frequency selective surfaces (FSSs) are introduced in order to improve the radiation parameters of the antenna. The operating frequency band of the tuneable rectangular MPA increases directly as the applied DC voltage bias is increased. Based on the simulation results, a tuneable rectangular MPA placed between two FSSs is proposed for fifth-generation applications.
Design and software implementation of radio frequency satellite link based on...TELKOMNIKA JOURNAL
The satellite communication providea utilization of radio frequency links. Specific frequencies are dedicated for satellite correspondences through global administrative and coordination procedures which keeps impedance amongframeworks. Over typical work, the satellite receives uplinked indicator fromearth. Progressions its frequency marginally will keep away from self-intervention then re-transmits signal ahead the downlink on the land. Pathloss depicts characteristic Propagate outside the sending signal front as it goes bythe space. A software defined radio (SDR) is a flexible technology that aimsto replace all hardware by software to enables the design of adaptive communications systems such as changing frequencies, modulation schemes and data rates. Applied to small satellites, some of the implications areincreased data through put when down-linking or up-linking by varying communications parameters and making use of one hardware design and implementation for communicating for many missions, just by updating the software. Therefore, development time for small satellite communication systems can be reduced in the future. This paper analyzes, design and software implementation of radio frequency satellite communications links under noisy channels such as phase/frequency offsets and noise temperature. Modulation schemes such as 64QAM system is used based on Matlab tools to implement the results. Obtained results shows a good response that get the goal from the paper.
11.smart antennas in 0004www.iiste.org call for paper_gAlexander Decker
This document summarizes a paper on smart antennas in 4G systems. It discusses how smart antennas work using an array of antenna elements and a digital signal processor to form beams. This allows for diversity gain, array gain, and interference suppression, improving capacity. Smart antennas can distinguish between propagation paths to transmit independent data streams or redundantly encode data. They can also suppress interference for conventional transmitters. Applications discussed include space division multiple access, beamforming basics, switched beam antennas, and use in mobile communications for increased gain and reduced interference.
System Consideration, Design and Implementation of Point To Point Microwave L...ijtsrd
Microwave technology is extremely used for point to point communications because it is more easily focused into narrower beams than radio waves, allowing frequency use, it is available higher data transmission rates and antenna sizes are smaller than at lower frequencies. The main aim of this system is to provide internet access for rural area using ePMP Force 180 5GHz subscriber module. The two sites are 1.45 km away from each other. GPS is used to determine the latitude and longitude of two sites location. Google Earth Pro software is used to check for line of sight in choosing potential terminal site locations. In this system, system consideration, design and analysis of line of sight microwave link and hardware implementations are to be carried out. In the analysis, path profile, Fresnel zone, link budget and other parameters are implemented using the link planner software Lay Nandar Soe | Kyaw Thet Zaw | Wai Phyo Aung "System Consideration, Design and Implementation of Point-To-Point Microwave Link for Internet Access" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-5 , August 2019, URL: https://www.ijtsrd.com/papers/ijtsrd26769.pdf Paper URL: https://www.ijtsrd.com/engineering/electronics-and-communication-engineering/26769/system-consideration-design-and-implementation-of-point-to-point-microwave-link-for-internet-access/lay-nandar-soe
Soft Frequency Reuse (SFR) in LTE-A Heterogeneous Networks based upon Power R...IJECEIAES
As the traffic demand grows and the RF environment changes, the mobile network relies on techniques such as SFR in Heterogeneous Network (HetNet) to overcome capacity and link budget limitation to maintain user experience. Inter-Cell Interference (ICI) strongly affecting Signal-toInterference plus Noise Ratio (SINR) of active UEs, especially cell-edge users, which leads to a significant degradation in the total throughput. In this paper we evaluate the performance of SFR with HetNet system in order dealing with interferences. Simulation result shows that the power ratio control in SFR HetNet system doesn’t have much effect on total achieved capacity for overall cell.
1. The document proposes an energy efficiency optimization power allocation (EEOPA) algorithm for multiuser multiple-input multiple-output (MU-MIMO) systems to improve energy efficiency.
2. In existing TDD MU-MIMO systems, high bit error rates result from imperfect channel state information. The proposed EEOPA algorithm aims to address this by optimizing power allocation.
3. The algorithm involves using quadrature amplitude modulation (QAM) and adapting the modulation scheme based on channel quality measurements to improve energy efficiency while maintaining low bit error rates. Simulation results show the algorithm can calculate SNR and BER to validate the energy efficiency gains.
The document analyzes the performance of vector antenna arrays compared to uniform linear arrays for code division multiple access (CDMA) signals in a multipath fading channel. It considers a closed loop power control system for a beamformer-RAKE receiver for a wireless CDMA system with multiple users. Both theoretical analysis and simulations show that vector antennas, which can detect six independent components of the electromagnetic field, can better exploit multipath diversity and significantly improve bit error rate performance over uniform linear arrays in frequency selective rich multipath channels. The vector antennas provide additional diversity to combat signal fading and improve interference suppression for multiple users.
Performance evaluation of path loss parameters for broadcasting applicationseSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Energy-efficient user association mechanism enabling fully hybrid spectrum sh...TELKOMNIKA JOURNAL
The document proposes an energy-efficient user association mechanism enabling fully hybrid spectrum sharing among multiple 5G cellular operators. It presents a network model with four independent operators, where each operator owns a set of mmWave base stations. The spectrum is divided into licensed, semi-shared, and fully-shared portions to serve users belonging to the different operators. The proposed QoE-based energy-efficient user association and fully hybrid spectrum sharing approach aims to maximize the energy efficiency of the four operators while maintaining a high quality of experience for users. Numerical results show that the approach can significantly improve energy efficiency for the operators compared to a maximum SINR-based approach, while still providing high quality of service to users.
Simulation and optimization of tuneable microstrip patch antenna for fifth-ge...IJECEIAES
Microstrip patch antennas (MPAs) are known largely for their versatility in terms of feasible geometries, making them applicable in many distinct circumstances. In this paper, a graphene-based tuneable single/array rectangular microstrip patch antenna (MPA) utilizing an inset feed technique designed to function in multiple frequency bands are used in a fifth-generation (5G) wireless communications system. The tuneable antenna is used to eliminate the difficulties caused by the narrow bandwidths typically associated with MPAs. The graphene material has a reconfigurable surface conductivity that can be adjusted to function at the required value, thus allowing the required resonance frequency to be selected. The simulated tuneable antenna comprises a copper radiating patch with four graphene strips used for tuning purposes and is designed to cover a wide frequency band. The proposed antenna can be tuned directly by applying a direct current (DC) voltage to the graphene strips, resulting in a variation in the surface impedance of the graphene strips and leading to shifts in the resonance frequency.
Paper Review: ENERGY-EFFICIENT WIRELESS COMMUNICATIONS TUTORIAL, SURVEY, AND ...Kaivalya Shah
This paper reviews energy-efficient wireless communications, providing an introduction to basic concepts, summarizing existing fundamental works and advanced techniques, and discussing open issues. Some techniques discussed include OFDMA networks, MIMO techniques, relay transmission, and resource allocation between signaling and data symbols. The paper concludes that while techniques like OFDMA, MIMO, and relaying can improve energy efficiency, joint optimization across techniques and consideration of practical factors is still needed, particularly for multi-user and multi-cell scenarios.
Performance Evaluation of PAPR Reduction with SER and BER by Modified Clippin...ijcsse
This paper work focuses on performance analysis of PAPR reduction of orthogonal frequency division multiplexing (OFDM) using amplitude clipping & filtering based design. Now a days one of the most proficient multi-carrier transmission techniques widely used today is orthogonal frequency division multiplexing (OFDM) which has been implemented by the next generation wireless communication technology: Long Term Evolution (LTE). Extra robustness to multipath fading and impulse noise is provided OFDM. It eliminates inter symbol interference (ISI) & inter carrier interference (ICI) with certain procedure. Therefore peak to average power ratio (PAPR) is the basic problem with OFDM. However in this paper we proposed a reduction procedure of the PAPR by using clipping and filtering. Here we use a composed high pass , low pass & Chevyshev band pass filter II after amplitude clipping to reduce the PAPR. The performance of the system in terms of bit error rate (BER) and symbol error rate (SER) is also investigated as a new filter based clipping method is proposed. Our proposed clipping method with and composed high pass the Chevyshev bandpass filter II in PAPR performance of the system with a little compromise of BER & SER showing the significant improvement in Quadrature Amplitude Modulation (QAM).
International Journal of Engineering and Science Invention (IJESI)inventionjournals
International Journal of Engineering and Science Invention (IJESI) is an international journal intended for professionals and researchers in all fields of computer science and electronics. IJESI publishes research articles and reviews within the whole field Engineering Science and Technology, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online.
Bit error rate analysis of miso system in rayleigh fading channeleSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Effect on Channel Capacity of Multi-User MIMO System in Crowded AreaIJEEE
1) The document analyzes the effect of multi-user MIMO (MU-MIMO) systems on channel capacity in crowded urban areas compared to single-user MIMO (SU-MIMO) systems.
2) It finds that MU-MIMO can achieve higher channel capacity than SU-MIMO in urban environments due to lower spatial correlation between users, unlike assumptions of independent channels in MIMO transmission.
3) The improvement of MU-MIMO capacity over SU-MIMO increases with path visibility, with MU-MIMO showing better performance when path visibility is over 13%.
COMPARISON BETWEEN ENERGY EFFICIENT COOPERATIVE MIMO AND COOPERATIVE RELAY IN...jantjournal
Wireless sensor network consists of thousand number of sensor nodes employed in a wide range of data gathering application such as environmental gathering, military applications etc. Each sensor node in WS N are powered by battery having limited energy so it is very difficult to replace there batteries for
prolonged the network life time. Maximizing the network lifetime have been most important design goal for the network. In WSN channel fading and radio interference constitute a big dispute in design of energy efficient communication protocol. To reduce fading and energy consumption in WSN, MIMO MISO SISO
scheme is employed but implement multiple antenna technology to sensor network is improbable because of the sensor node generally support a single antenna. Cooperative scheme are utilized in WSN by applying the collective nature of the sensor nodes to provide reliable communication links in order to lower the total energy consumption. In this paper, the cooperative technique are inspected and by comparing different
cooperative techniques we can elect the best cooperative scheme for energy constrained WS N application.
This document describes a gesture-controlled robot that uses image processing and an Arduino board. The robot has two wheels driven by motors connected to an L293D motor driver circuit. An Arduino board controls the motor driver circuit. A Python program uses OpenCV to detect hand gestures based on colored objects. When an object of a certain color moves in different directions, the Python program sends signals to the Arduino board to move the robot forward, backward, left or right. The Python program and Arduino program communicate over serial to control the robot's movement based on hand gestures.
This document describes the design and analysis of an image-activated street light system. The system uses a light dependent resistor (LDR) sensor that is placed outside of the system casing to detect light and dark conditions. When the LDR senses darkness, it acts as a switch to turn on the circuit and provide a 220V output that can power street lights. When the LDR senses light, it automatically switches off the circuit. The system is designed to operate automatically without any manual switching in response to environmental light conditions detected by the LDR sensor. The document provides details on the system components, including the power control unit, operating sensor unit, and control system, and analyzes the performance of the image-activated switch design
Numerical Solution for the Design of a Traditional Aerospike Nozzle using Met...IOSR Journals
This document describes a numerical method for designing a traditional aerospike nozzle contour using the method of characteristics. The method discretizes the characteristic and compatibility equations and applies boundary conditions to define a characteristic net. Points along the nozzle contour are determined by satisfying the stream function within the characteristic net, sweeping through the expansion fan in small increments of Prandtl-Meyer expansion angle. The accuracy of the numerical method is verified by comparing the exit Mach number and area ratio to theoretical values and running CFD simulations with ANSYS-FLUENT. Good agreement is achieved when using small increments of the expansion angle.
Limitation of Maasive MIMO in Antenna CorrelationVARUN KUMAR
The document discusses the limitations of massive MIMO systems due to antenna correlation. It presents a system model to analyze the impact of antenna correlation on achievable rates and power efficiency. Simulation results show that antenna correlation significantly degrades performance compared to an uncorrelated channel. The document concludes that while massive MIMO provides diversity, antenna proximity causes correlation and coupling which cannot be solved by increasing antenna spacing alone under physical space constraints at the base station.
Simulation and optimization of a tuneable rectangular microstrip patch antenn...TELKOMNIKA JOURNAL
In this paper, a tuneable rectangular microstrip patch antenna (MPA) is simulated and optimized to operate in four frequency bands of the next generation of wireless communication systems. The proposed design incorporates a copper radiating patch with four implanted graphene strips for tuning purposes. The reconfigurable surface impedance of graphene can easily be altered by applying a DC voltage bias directly to the graphene strips, allowing the operating frequency of the antenna to be tuned as desired. The capability of the applied voltage to tune the operating frequency band of the proposed antenna is studied via computer simulation technology (CST) microwave studio (MWS). Frequency selective surfaces (FSSs) are introduced in order to improve the radiation parameters of the antenna. The operating frequency band of the tuneable rectangular MPA increases directly as the applied DC voltage bias is increased. Based on the simulation results, a tuneable rectangular MPA placed between two FSSs is proposed for fifth-generation applications.
Design and software implementation of radio frequency satellite link based on...TELKOMNIKA JOURNAL
The satellite communication providea utilization of radio frequency links. Specific frequencies are dedicated for satellite correspondences through global administrative and coordination procedures which keeps impedance amongframeworks. Over typical work, the satellite receives uplinked indicator fromearth. Progressions its frequency marginally will keep away from self-intervention then re-transmits signal ahead the downlink on the land. Pathloss depicts characteristic Propagate outside the sending signal front as it goes bythe space. A software defined radio (SDR) is a flexible technology that aimsto replace all hardware by software to enables the design of adaptive communications systems such as changing frequencies, modulation schemes and data rates. Applied to small satellites, some of the implications areincreased data through put when down-linking or up-linking by varying communications parameters and making use of one hardware design and implementation for communicating for many missions, just by updating the software. Therefore, development time for small satellite communication systems can be reduced in the future. This paper analyzes, design and software implementation of radio frequency satellite communications links under noisy channels such as phase/frequency offsets and noise temperature. Modulation schemes such as 64QAM system is used based on Matlab tools to implement the results. Obtained results shows a good response that get the goal from the paper.
11.smart antennas in 0004www.iiste.org call for paper_gAlexander Decker
This document summarizes a paper on smart antennas in 4G systems. It discusses how smart antennas work using an array of antenna elements and a digital signal processor to form beams. This allows for diversity gain, array gain, and interference suppression, improving capacity. Smart antennas can distinguish between propagation paths to transmit independent data streams or redundantly encode data. They can also suppress interference for conventional transmitters. Applications discussed include space division multiple access, beamforming basics, switched beam antennas, and use in mobile communications for increased gain and reduced interference.
System Consideration, Design and Implementation of Point To Point Microwave L...ijtsrd
Microwave technology is extremely used for point to point communications because it is more easily focused into narrower beams than radio waves, allowing frequency use, it is available higher data transmission rates and antenna sizes are smaller than at lower frequencies. The main aim of this system is to provide internet access for rural area using ePMP Force 180 5GHz subscriber module. The two sites are 1.45 km away from each other. GPS is used to determine the latitude and longitude of two sites location. Google Earth Pro software is used to check for line of sight in choosing potential terminal site locations. In this system, system consideration, design and analysis of line of sight microwave link and hardware implementations are to be carried out. In the analysis, path profile, Fresnel zone, link budget and other parameters are implemented using the link planner software Lay Nandar Soe | Kyaw Thet Zaw | Wai Phyo Aung "System Consideration, Design and Implementation of Point-To-Point Microwave Link for Internet Access" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-5 , August 2019, URL: https://www.ijtsrd.com/papers/ijtsrd26769.pdf Paper URL: https://www.ijtsrd.com/engineering/electronics-and-communication-engineering/26769/system-consideration-design-and-implementation-of-point-to-point-microwave-link-for-internet-access/lay-nandar-soe
Soft Frequency Reuse (SFR) in LTE-A Heterogeneous Networks based upon Power R...IJECEIAES
As the traffic demand grows and the RF environment changes, the mobile network relies on techniques such as SFR in Heterogeneous Network (HetNet) to overcome capacity and link budget limitation to maintain user experience. Inter-Cell Interference (ICI) strongly affecting Signal-toInterference plus Noise Ratio (SINR) of active UEs, especially cell-edge users, which leads to a significant degradation in the total throughput. In this paper we evaluate the performance of SFR with HetNet system in order dealing with interferences. Simulation result shows that the power ratio control in SFR HetNet system doesn’t have much effect on total achieved capacity for overall cell.
1. The document proposes an energy efficiency optimization power allocation (EEOPA) algorithm for multiuser multiple-input multiple-output (MU-MIMO) systems to improve energy efficiency.
2. In existing TDD MU-MIMO systems, high bit error rates result from imperfect channel state information. The proposed EEOPA algorithm aims to address this by optimizing power allocation.
3. The algorithm involves using quadrature amplitude modulation (QAM) and adapting the modulation scheme based on channel quality measurements to improve energy efficiency while maintaining low bit error rates. Simulation results show the algorithm can calculate SNR and BER to validate the energy efficiency gains.
The document analyzes the performance of vector antenna arrays compared to uniform linear arrays for code division multiple access (CDMA) signals in a multipath fading channel. It considers a closed loop power control system for a beamformer-RAKE receiver for a wireless CDMA system with multiple users. Both theoretical analysis and simulations show that vector antennas, which can detect six independent components of the electromagnetic field, can better exploit multipath diversity and significantly improve bit error rate performance over uniform linear arrays in frequency selective rich multipath channels. The vector antennas provide additional diversity to combat signal fading and improve interference suppression for multiple users.
Performance evaluation of path loss parameters for broadcasting applicationseSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Energy-efficient user association mechanism enabling fully hybrid spectrum sh...TELKOMNIKA JOURNAL
The document proposes an energy-efficient user association mechanism enabling fully hybrid spectrum sharing among multiple 5G cellular operators. It presents a network model with four independent operators, where each operator owns a set of mmWave base stations. The spectrum is divided into licensed, semi-shared, and fully-shared portions to serve users belonging to the different operators. The proposed QoE-based energy-efficient user association and fully hybrid spectrum sharing approach aims to maximize the energy efficiency of the four operators while maintaining a high quality of experience for users. Numerical results show that the approach can significantly improve energy efficiency for the operators compared to a maximum SINR-based approach, while still providing high quality of service to users.
Simulation and optimization of tuneable microstrip patch antenna for fifth-ge...IJECEIAES
Microstrip patch antennas (MPAs) are known largely for their versatility in terms of feasible geometries, making them applicable in many distinct circumstances. In this paper, a graphene-based tuneable single/array rectangular microstrip patch antenna (MPA) utilizing an inset feed technique designed to function in multiple frequency bands are used in a fifth-generation (5G) wireless communications system. The tuneable antenna is used to eliminate the difficulties caused by the narrow bandwidths typically associated with MPAs. The graphene material has a reconfigurable surface conductivity that can be adjusted to function at the required value, thus allowing the required resonance frequency to be selected. The simulated tuneable antenna comprises a copper radiating patch with four graphene strips used for tuning purposes and is designed to cover a wide frequency band. The proposed antenna can be tuned directly by applying a direct current (DC) voltage to the graphene strips, resulting in a variation in the surface impedance of the graphene strips and leading to shifts in the resonance frequency.
Paper Review: ENERGY-EFFICIENT WIRELESS COMMUNICATIONS TUTORIAL, SURVEY, AND ...Kaivalya Shah
This paper reviews energy-efficient wireless communications, providing an introduction to basic concepts, summarizing existing fundamental works and advanced techniques, and discussing open issues. Some techniques discussed include OFDMA networks, MIMO techniques, relay transmission, and resource allocation between signaling and data symbols. The paper concludes that while techniques like OFDMA, MIMO, and relaying can improve energy efficiency, joint optimization across techniques and consideration of practical factors is still needed, particularly for multi-user and multi-cell scenarios.
Performance Evaluation of PAPR Reduction with SER and BER by Modified Clippin...ijcsse
This paper work focuses on performance analysis of PAPR reduction of orthogonal frequency division multiplexing (OFDM) using amplitude clipping & filtering based design. Now a days one of the most proficient multi-carrier transmission techniques widely used today is orthogonal frequency division multiplexing (OFDM) which has been implemented by the next generation wireless communication technology: Long Term Evolution (LTE). Extra robustness to multipath fading and impulse noise is provided OFDM. It eliminates inter symbol interference (ISI) & inter carrier interference (ICI) with certain procedure. Therefore peak to average power ratio (PAPR) is the basic problem with OFDM. However in this paper we proposed a reduction procedure of the PAPR by using clipping and filtering. Here we use a composed high pass , low pass & Chevyshev band pass filter II after amplitude clipping to reduce the PAPR. The performance of the system in terms of bit error rate (BER) and symbol error rate (SER) is also investigated as a new filter based clipping method is proposed. Our proposed clipping method with and composed high pass the Chevyshev bandpass filter II in PAPR performance of the system with a little compromise of BER & SER showing the significant improvement in Quadrature Amplitude Modulation (QAM).
International Journal of Engineering and Science Invention (IJESI)inventionjournals
International Journal of Engineering and Science Invention (IJESI) is an international journal intended for professionals and researchers in all fields of computer science and electronics. IJESI publishes research articles and reviews within the whole field Engineering Science and Technology, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online.
Bit error rate analysis of miso system in rayleigh fading channeleSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Effect on Channel Capacity of Multi-User MIMO System in Crowded AreaIJEEE
1) The document analyzes the effect of multi-user MIMO (MU-MIMO) systems on channel capacity in crowded urban areas compared to single-user MIMO (SU-MIMO) systems.
2) It finds that MU-MIMO can achieve higher channel capacity than SU-MIMO in urban environments due to lower spatial correlation between users, unlike assumptions of independent channels in MIMO transmission.
3) The improvement of MU-MIMO capacity over SU-MIMO increases with path visibility, with MU-MIMO showing better performance when path visibility is over 13%.
COMPARISON BETWEEN ENERGY EFFICIENT COOPERATIVE MIMO AND COOPERATIVE RELAY IN...jantjournal
Wireless sensor network consists of thousand number of sensor nodes employed in a wide range of data gathering application such as environmental gathering, military applications etc. Each sensor node in WS N are powered by battery having limited energy so it is very difficult to replace there batteries for
prolonged the network life time. Maximizing the network lifetime have been most important design goal for the network. In WSN channel fading and radio interference constitute a big dispute in design of energy efficient communication protocol. To reduce fading and energy consumption in WSN, MIMO MISO SISO
scheme is employed but implement multiple antenna technology to sensor network is improbable because of the sensor node generally support a single antenna. Cooperative scheme are utilized in WSN by applying the collective nature of the sensor nodes to provide reliable communication links in order to lower the total energy consumption. In this paper, the cooperative technique are inspected and by comparing different
cooperative techniques we can elect the best cooperative scheme for energy constrained WS N application.
This document describes a gesture-controlled robot that uses image processing and an Arduino board. The robot has two wheels driven by motors connected to an L293D motor driver circuit. An Arduino board controls the motor driver circuit. A Python program uses OpenCV to detect hand gestures based on colored objects. When an object of a certain color moves in different directions, the Python program sends signals to the Arduino board to move the robot forward, backward, left or right. The Python program and Arduino program communicate over serial to control the robot's movement based on hand gestures.
This document describes the design and analysis of an image-activated street light system. The system uses a light dependent resistor (LDR) sensor that is placed outside of the system casing to detect light and dark conditions. When the LDR senses darkness, it acts as a switch to turn on the circuit and provide a 220V output that can power street lights. When the LDR senses light, it automatically switches off the circuit. The system is designed to operate automatically without any manual switching in response to environmental light conditions detected by the LDR sensor. The document provides details on the system components, including the power control unit, operating sensor unit, and control system, and analyzes the performance of the image-activated switch design
Numerical Solution for the Design of a Traditional Aerospike Nozzle using Met...IOSR Journals
This document describes a numerical method for designing a traditional aerospike nozzle contour using the method of characteristics. The method discretizes the characteristic and compatibility equations and applies boundary conditions to define a characteristic net. Points along the nozzle contour are determined by satisfying the stream function within the characteristic net, sweeping through the expansion fan in small increments of Prandtl-Meyer expansion angle. The accuracy of the numerical method is verified by comparing the exit Mach number and area ratio to theoretical values and running CFD simulations with ANSYS-FLUENT. Good agreement is achieved when using small increments of the expansion angle.
Design, Construction and Operation of a 4-Bit Counting CircuitIOSR Journals
This document describes the design, construction, and operation of a 4-bit binary counting circuit. The circuit uses a PIC microcontroller as the central processing unit. It has four light emitting diodes (LEDs) to display the binary output and a dual seven-segment display to show the decimal equivalent. The microcontroller processes the binary information and controls the LEDs and display. The circuit was tested and able to count from 0000 to 1111 binary and 0 to 15 in decimal as each count pulse was received.
This document describes using particle swarm optimization (PSO) to detect defective elements in a spaceborne planar antenna array. PSO is an optimization technique that models social behavior to iteratively find the global minimum of a cost function. Here, PSO is used to minimize the difference between measured and expected far-field radiation patterns to determine the location of any defective array elements. The document outlines designing a 2x2 planar array in IE3D software, introducing defects, calculating error patterns, and using PSO to optimize element positions to minimize error and correctly identify defective elements based only on far-field power measurements. The technique is shown to successfully detect randomly defective elements in the array, making it useful for locating failures in space applications where
1. The document describes the development of a helmet detection system and smart seat belt system for dune buggies. The system uses an ultrasonic sensor to detect the presence of a helmet and prevents the vehicle from starting if a helmet is not detected.
2. It also incorporates a seat belt switch that checks if the seat belt is fastened and will not allow the vehicle to start if the seat belt is not fastened.
3. The system is intended to increase safety by ensuring drivers and passengers wear helmets and seat belts, which can reduce injuries during accidents. Various tests showed the system was able to prevent the vehicle from starting when proper safety gear was not worn.
This document evaluates the hydraulic conductivity of a marble dust-soil composite. Laboratory tests were conducted to determine the index properties and compaction characteristics of a clayey soil treated with 0-20% marble dust. Hydraulic conductivity tests using a consolidometer found that permeability decreased with up to 12.5% marble dust addition and remained constant thereafter. Permeability also decreased with higher compaction moisture content. Based on the results, 25% marble dust addition was proposed to satisfy the regulatory permeability requirement of ≤ 1 x 10-9 m/s for landfill liner materials.
This document compares the performance of the OSPF and MPLS protocols using network simulation in OPNET. It describes the key aspects of each protocol and the simulation methodology. The results of the simulation show that OSPF had higher throughput and utilization than MPLS, while MPLS had approximately 50% higher delay. In conclusion, OSPF performed better in terms of throughput and utilization, while MPLS had higher delay.
This document summarizes an experiment investigating the electrochemical behavior of carbon steel used for nuclear reactor containment buildings. Potentiodynamic, potentiostatic, and galvanostatic polarization techniques were used to study the steel's behavior in Ca(OH)2 solutions with varying NaCl concentrations. It was found that pitting occurred on the steel in solutions above a certain chloride concentration threshold that decreased with increasing chloride levels. Galvanostatic tests determined the chloride threshold conditions for depassivation of the pre-passivated steel. Optical microscopy of polarized samples confirmed localized corrosion above the threshold.
The document summarizes research on using activated flux in TIG welding of mild steel. Activated TIG welding involves brushing a thin layer of activated flux onto the welding joint before welding. Several studies found that activated flux can increase weld penetration, reduce weld width, and increase the depth-to-width ratio compared to conventional TIG welding. Cr2O3 flux produced the most significant effects in one study, increasing penetration on mild steel while decreasing hardness and increasing the depth-to-width ratio. Overall, activated flux aided TIG welding has been shown to improve weld quality and mechanical properties for mild steel compared to conventional TIG welding.
This document describes the design and fabrication of a downdraft gasifier to be used with an internal combustion (I.C.) engine. The gasifier is designed to run on rice husk and wood pellets as biomass fuels. It will convert the biomass into syngas through pyrolysis and partial oxidation in the gasifier. The syngas can then be used to run a 4KW I.C. engine. The document outlines the design process including calculations of throughput requirements and component sizing. Details of material selection, fabrication, and planned experimentation are also provided. The gasifier is expected to reduce fuel consumption and provide a sustainable energy alternative while producing low-tar syngas suitable for the
This document analyzes the NACA 6412 airfoil for use as a propeller on a flying bike. It summarizes the analysis conducted using JavaProp software. The analysis found that a two-blade propeller with the NACA 6412 airfoil would produce sufficient thrust for the flying bike while keeping weight low. Under shrouded and squared tip conditions, thrust was maximized. The analysis validated thrust values against prior mathematical modeling, meeting targets with less than 0.02% difference. It was concluded that a two-blade propeller would be better than three blades for this application due to better weight efficiency while producing equivalent thrust.
An Assessment on Food Security in Developing Economies-Problems and Policy In...IOSR Journals
This document discusses food security in developing economies and policy initiatives to address it. It begins by defining food security as access to sufficient nutritious food. Over 800 million people in developing countries lack adequate food. Food security indicators measure availability, access, and utilization. The FAO reported that in 2010-2012, almost 870 million people were undernourished, with higher rates in developing countries. India has added 30 million hungry people since the 1990s and 46% of children are underweight. The document examines food security challenges and measures in developing economies and the US, and initiatives by UN agencies to improve global food security.
Physical Fitness Index of Indian Judo Players assessed by Harvard step test.IOSR Journals
This study assessed the physical fitness index of 31 Indian judo players using the Harvard step test and compared it to 31 sedentary controls. The judo players were divided into two groups based on duration of training: Group A trained for 5 years or less, Group B trained for over 5 years. Group B showed a significantly higher physical fitness index than Group A. Both judo player groups had a higher index than the controls. A positive correlation was also found between physical fitness index and performance in a special judo fitness test, suggesting higher fitness is associated with better judo performance. The results indicate that longer training duration has a positive effect on physical fitness levels in judo players.
This document analyzes the admittance characteristics of an H-plane tee junction formed by coupling two rectangular waveguides of different bands through an inclined slot in the narrow wall. The analysis uses concepts of self-reaction and discontinuity in modal current to determine the admittance loading, coupling, and voltage standing wave ratio as functions of slot width, length, and inclination angle. Results are compared to practical measurements. Previous work analyzing longitudinal and transverse slots is discussed, but no prior literature examines an inclined slot between waveguides of different bands.
IOSR Journal of Applied Physics (IOSR-JAP) is an open access international journal that provides rapid publication (within a month) of articles in all areas of physics and its applications. The journal welcomes publications of high quality papers on theoretical developments and practical applications in applied physics. Original research papers, state-of-the-art reviews, and high quality technical notes are invited for publications.
This document provides a comparative study of 4G and 5G wireless technologies. Some key points:
- 4G networks are based on LTE technology using MIMO and OFDM to achieve high data throughput. 5G will provide even higher speeds and connectivity for many devices.
- 5G will operate at higher frequencies of 3-300GHz and support data rates over 1Gbps for many connections. It is designed to handle a wide variety of connected devices and traffic types.
- 5G networks will use technologies like cloud RAN and virtual RAN for more centralized network establishment. They will also use cognitive radio techniques to dynamically adapt to conditions.
- When 5G replaces 4G, it aims
Effect of Different Levels of Cadmium, Lead and Arsenic on the Growth Perform...IOSR Journals
This document summarizes a study on the effects of different levels of cadmium, lead, and arsenic on the growth performance of broiler and layer chickens. Sixteen one-day-old chicks were fed feeds mixed with 0ppm, 10ppm, 20ppm, or 30ppm of the heavy metals. Results showed heavy metal accumulation in organs increased with concentration. Body weights decreased remarkably as metal concentrations increased, with 30ppm chickens weighing 820-1100g versus 1800-2350g for 0ppm at 56 days. Feed intake also decreased with higher metal levels. The study concludes that increasing heavy metal concentrations in poultry feed can retard growth rates and body weights.
This document discusses hybrid renewable energy systems and their suitability for rural regions in India. It notes that about 75% of India's population lives in rural areas that often face electricity shortages, hindering development. Hybrid systems that combine two or more renewable sources like biomass, wind, solar, and hydro could help address this issue by providing a more reliable supply. The document outlines several hybrid system examples and notes their advantages like increased reliability, flexibility, and lower operating costs compared to individual renewable systems. However, hybrid systems also present challenges like complex power conditioning, stochastic resource availability, and coordination with electric grids.
This document proposes a new approach called Embedded Condition Based Maintenance (ECBM) that aims to improve existing Condition Based Maintenance (CBM) systems. ECBM would use diagnostic and prognostic signals that are already embedded in industrial control systems, rather than additional sensors. This would make ECBM lower cost and faster at fault detection compared to traditional CBM. The document discusses challenges with CBM, outlines the proposed ECBM approach, and describes how ECBM would use clustering, intelligent schemes and Petri nets with existing control modules to perform online fault detection and maintenance recommendations.
Proposed Model for Interference Estimation in Code Division Multiple AccessTELKOMNIKA JOURNAL
Cellular CDMA systems are usually affected by interference experienced by users in adjacent
cells that decrease the Quality of Services in wireless communication network. Hence, interference is the
limiting factor of capacity in CDMA cellular and it is one of the problems fighting against the high efficiency
of any mobile network. In this paper, a mathematical model to estimate the average number of users
contributing in inter-cell interference at the busy hours of CDMA network is proposed. As the power
exponent value has significant affect on interferer signal attenuation and hence other-cells interference,
measurements were carried through a drive test to determine the received power level at various distance
from CDMA base stations at Baghdad. The results obtained show that the power exponent was 2.71. This
value was applied in dual-slop path loss model to determine the expected interference factor, and the
number of users that can be hold at each cell. Simulations showed that users at a boundary cell generate
more interference than those close to the base station. Furthermore, it was denoted that greater number of
users caused to increase the interference factor, and greater power exponent value result in interference
factor reduction.
COMPARISON OF BER AND NUMBER OF ERRORS WITH DIFFERENT MODULATION TECHNIQUES I...Sukhvinder Singh Malik
This paper provides analysis of BER and Number of Errors for MIMO-OFDM wireless communication system by using different modulation techniques. Wireless designers constantly seek to improve the spectrum efficiency/capacity, coverage of wireless networks, and link reliability. So the performances of the wireless communication systems can be enhanced by using multiple transmit and receive antennas, which is generally referred to as the MIMO technique. Here analysis will be carried out for an OFDM wireless communication system using different modulation techniques and considering the effect and the wireless channel like AWGN, fading. Performance results will be evaluated numerically and graphically using the plots of BER versus SNR and plots of number of errors versus SNR.
Compared to wireless deployment in areas with different environmentseIJECEIAES
In the mobile phone system, it is highly desirable to estimate the loss of the track not only to improve performance but also to achieve an accurate estimate of financial feasibility; the inaccurate estimate of track loss either leads to performance degradation or increased cost. Various models have been introduced to accurately estimate the path loss. One of these models is the Okomura / Hata model, which is recommended for estimating path loss in cellular systems that use micro cells. This system is suitable for use in a variety of environments. This study examines the comparison of path loss models for statistical analysis derived from experimental data collected in urban and suburban areas at frequencies of 150-1500 MHz’s The results of the measurements were used to develop path loss models in urban and suburban areas. The results showed that Pathloss increases in urban areas respectively.
K Coverage Probability of 5G Wireless Cognitive Radio Network under Shadow Fa...ijeei-iaes
Land mobile communication is burdened with typical propagation constraints due to the channel characteristics in radio systems.Also,the propagation characteristics vary form place to place and also as the mobile unit moves,from time to time.Hence,the tramsmission path between transmitter and receiver varies from simple direct LOS to the one which is severely obstructed by buildings,foliage and terrain.Multipath propagation and shadow fading effects affect the signal strength of an arbitrary Transmitter-Receiver due to the rapid fluctuations in the phase and amplitude of signal which also determines the average power over an area of tens or hundreds of meters.Shadowing introduces additional fluctuations,so the received local mean power varies around the area –mean.The present section deals with the performance analysis of fifth generation wireless cognitive radio network on the basis of signal and interference level based k coverage probability under the shadow fading effects.
This document summarizes research on improving the capacity of cellular systems using fractional frequency reuse (FFR). It discusses how frequency reuse is used to increase the number of users that can be served but causes interference, particularly for cell edge users. Fractional frequency reuse is proposed to solve this problem by allocating different frequency sets to cell center and edge users to reduce interference. The document also reviews different types of interference (co-channel and adjacent channel) and how power control can help reduce interference in cellular systems.
Capacity Improvement of Cellular System Using Fractional Frequency Reuse (FFR)IJEEE
Today wireless communication is mostly used rather than wired communication, due to remote location reach ability, less fault occurrence, less time to commissioning and low cost etc. But wireless network has less frequency spectrum to cover the whole world. To improve the capacity of cellular system in a limited spectrum without major technological changes, frequency is reused in cells. But it offers interferences mostly for cell edge users. To solve the problem of spectral congestion and user capacity, fractional frequency reuse is used. This paper gives idea about different frequency reuse factors, fractional frequency reuse and super cell with sectoring to improve the capacity of cellular system.
Coverage and Capacity Performance Degradation on a Co-Located Network Involvi...Onyebuchi nosiri
The document investigates the performance effects of noise rise caused by spurious emission from a co-located jammer on the coverage radius and system capacity of a CDMA2000 and WCDMA network. Measurements were taken to evaluate the impact of increasing noise rise on these parameters. The results showed that as noise rise increased due to spurious emission, the coverage radius and number of supported users decreased, reducing system capacity. A noise rise of 2dB represented a 15 user reduction and 33% lower capacity. The study concludes noise rise degradation impacts must be controlled to maintain desired coverage area and capacity performance.
Coverage and Capacity Performance Degradation on a Co-Located Network Involvi...Onyebuchi nosiri
Abstract—Coverage and capacity performance in a cellular network determines the system potentials. If the coverage radius is limited, end users suffer poor service quality, if the system capacity reduces, fewer subscribers will be accommodated. This paper investigated the performance effects of the noise rise caused by the spurious emission from a co-located jammer involving downlink frequency of CDMA2000 and uplink frequency of WCDMA operating at 1.9GHz. Measurements were carried out to evaluate the impact on the coverage radius and the system capacity.
RESOURCE ALLOCATION TECHNIQUE USING LOAD MATRIX METHOD IN WIRELESS CELLULAR S...cscpconf
An efficient resource allocation is one of the greatest challenges in wireless cellular
communication. The resource allocation schemes avoid wastage of resources by allocating
resources to a mobile terminal over a short period of time, providing quality of service over
wireless networks is the most stressing point for service providers. In general a high degree of
sharing is efficient, but requires service protection mechanisms to guarantee the QoS for all
services. In this paper we address the multi cell interference on overall radio resource
utilization and propose a new strategy for resource allocation in multi cell systems. we also
propose a joint management of interference within and between cells for allocation of radio
resources , Simulation results are showing that there is a significant improvement in the resource utilization so that overall network performance.
This document describes the parameters and models used to evaluate the link budget for 900MHz GSM communication services. It considers factors such as transmitter power, antenna gains, losses, propagation path loss, and rain attenuation. Path loss models discussed include free space, Okumura, and Hata models. Rain attenuation is calculated using the ITU model. An example link budget is provided for an urban area in Lagos, Nigeria that incorporates the calculated rain attenuation to improve communication during rainfall.
This document discusses evaluating the link budget for effective 900MHz GSM communication. It describes the basic parameters needed for a high-level link budget calculation, including transmitter power, antenna gains, path loss, and propagation models. Common propagation models for 900MHz that are described include Okumura model for urban areas and Hata model for urban, suburban, and open areas. Rain attenuation is also incorporated using the updated ITU model to improve communication during rainfall.
Impact of Next Generation Cognitive Radio Network on the Wireless Green Eco s...ijeei-iaes
Land mobile communication is burdened with typical propagation constraints due to the channel characteristics in radio systems.Also,the propagation characteristics vary form place to place and also as the mobile unit moves,from time to time.Hence,the tramsmission path between transmitter and receiver varies from simple direct LOS to the one which is severely obstructed by buildings, foliage and terrain. Multipath propagation and shadow fading effects affect the signal strength of an arbitrary Transmitter-Receiver due to the rapid fluctuations in the phase and amplitude of signal which also determines the average power over an area of tens or hundreds of meters. Shadowing introduces additional fluctuations, so the received local mean power varies around the area –mean. The present paper deals with the performance analysis of impact of next generation wireless cognitive radio network on wireless green eco system through signal and interference level based k coverage probability under the shadow fading effects.
Radio field strength propagation data and pathloss calculation methods in umt...Alexander Decker
This document discusses radio signal path loss prediction methods for UMTS networks. It conducted field measurements of signal strength in a UMTS network in Benin City, Nigeria to collect propagation data. It then used this data to calculate path loss and compared the results to several existing path loss prediction models, finding that the Okumura-Hata model provided the closest predictions for the environment studied, showing its suitability for path loss analysis in UMTS networks in urban areas.
Performance of modeling wireless networks in realistic environmentCSCJournals
A wireless network is realized by mobile devices which communicate over radio channels. Since, experiments of real life problem with real devices are very difficult, simulation is used very often. Among many other important properties that have to be defined for simulative experiments, the mobility model and the radio propagation model have to be selected carefully. Both have strong impact on the performance of mobile wireless networks, e.g., the performance of routing protocols varies with these models. There are many mobility and radio propagation models proposed in literature. Each of them was developed with different objectives and is not suited for every physical scenario. The radio propagation models used in common wireless network simulators, in general researcher consider simple radio propagation models and neglect obstacles in the propagation environment. In this paper, we study the performance of wireless networks simulation by consider different Radio propagation models with considering obstacles in the propagation environment. In this paper we analyzed the performance of wireless networks by OPNET Modeler .In this paper we quantify the parameters such as throughput, packet received attenuation.
Secure and Energy Savings Communication of Flying Ad Hoc Network for Rescue O...BRNSSPublicationHubI
This document summarizes a research article about developing a secure and energy-efficient routing protocol for Flying Ad Hoc Networks (FANETs) used in rescue operations. The protocol aims to address issues like lack of congestion control, reliability, and high energy consumption in FANETs. It proposes forming clusters of flying nodes based on distance and energy levels. It then calculates remaining energy of nodes to save resources. Finally, it establishes communication between clusters and a ground operation center using node velocity and location data. The goal is to enable secure and energy-efficient communication for coordinating rescue efforts using a rapidly deployable FANET.
Third Generation Wireless Modeling in Urban EnvironmentEECJOURNAL
The global mobile communication is fast growing in industry. This paper recommends appropriate settings to evaluate the performance of wireless mobile system deploying third generation networks in an urban environment. To meet this aim, a case Study of Sulaimanyia city is considered for this study by establishing suitable radio channel models. The work presents a statistical channel model, where fixed and nomadic analysis services are considered in the simulated radio coverage scenario. The cartographic dataset had been collected, and Matlab Software was used for showing the analysis and simulation results. Statistical channel models are derived that combine standard parameters such as separation distance, operating frequency and terminal height with more advanced and innovative parameters such as distance dependent shadowing and LOS probability.
THE PERFORMANCE OF CONVOLUTIONAL CODING BASED COOPERATIVE COMMUNICATION: RELAYIJCNCJournal
Wireless communication faces adversities due to noise, fading, and path loss. Multiple-Input MultipleOutput (MIMO) systems are used to overcome individual fading effect by employing transmit diversity. Duo to user single-antenna, Cooperation between at least two users is able to provide spatial diversity. This paper presents the evaluation of the performances of the Amplify and Forward (AF) cooperative system for different relay positions using several network topologies over Rayleigh and Rician fading channel. Furthermore, we present the performances of AF cooperative system with various power allocation. The results show that cooperative communication with convolutional coding shows an outperformance compared to the non-convolutional, which is a promising solution for high data-rate networks such as (WSN), Ad hoc, (IoT), and even mobile networks. When topologies are compared, the simulation shows that, linear topology offers the best BER performance, in contrast when the relay acts as source and the source take the relay place, the analysis result shows that, equilateral triangle topology has the best BER performance and stability, and the system performance with inter-user Rician fading channel is better than the performance of the system with inter-user Rayleigh fading channel.
Multi user-MIMO Broadcast Channel techniquesIRJET Journal
This document provides an overview of techniques for multi-user MIMO broadcast channels, including block diagonalization, dirty paper coding, and zero forcing channel inversion. Block diagonalization uses precoding to suppress interference between users by making each user's channel orthogonal. Dirty paper coding codes signals to cancel out interference that is known at the transmitter. Zero forcing channel inversion inverts the channel and applies precoding to eliminate multi-user interference. These techniques aim to reconstruct signals and remove interference to maintain reliable data transmission in multi-user MIMO systems.
The document discusses the impact of sectorization on UMTS radio access network coverage planning. It analyzes three different site layout configurations: single omni-directional antenna sites, 3-sector sites, and 6-sector sites. The number of sites required to cover a deployment area is estimated for each configuration. Sectorized sites use high gain directional antennas to cover sectors, replacing omni-directional antennas. Link budget calculations are performed to determine the maximum path loss and cell radius for different clutter types. The results can be used to study the effect of sectorization and antenna gain on the number of sites needed.
This document provides a technical review of secure banking using RSA and AES encryption methodologies. It discusses how RSA and AES are commonly used encryption standards for secure data transmission between ATMs and bank servers. The document first provides background on ATM security measures and risks of attacks. It then reviews related work analyzing encryption techniques. The document proposes using a one-time password in addition to a PIN for ATM authentication. It concludes that implementing encryption standards like RSA and AES can make transactions more secure and build trust in online banking.
This document analyzes the performance of various modulation schemes for achieving energy efficient communication over fading channels in wireless sensor networks. It finds that for long transmission distances, low-order modulations like BPSK are optimal due to their lower SNR requirements. However, as transmission distance decreases, higher-order modulations like 16-QAM and 64-QAM become more optimal since they can transmit more bits per symbol, outweighing their higher SNR needs. Simulations show lifetime extensions up to 550% are possible in short-range networks by using higher-order modulations instead of just BPSK. The optimal modulation depends on transmission distance and balancing the energy used by electronic components versus power amplifiers.
This document provides a review of mobility management techniques in vehicular ad hoc networks (VANETs). It discusses three modes of communication in VANETs: vehicle-to-infrastructure (V2I), vehicle-to-vehicle (V2V), and hybrid vehicle (HV) communication. For each communication mode, different mobility management schemes are required due to their unique characteristics. The document also discusses mobility management challenges in VANETs and outlines some open research issues in improving mobility management for seamless communication in these dynamic networks.
This document provides a review of different techniques for segmenting brain MRI images to detect tumors. It compares the K-means and Fuzzy C-means clustering algorithms. K-means is an exclusive clustering algorithm that groups data points into distinct clusters, while Fuzzy C-means is an overlapping clustering algorithm that allows data points to belong to multiple clusters. The document finds that Fuzzy C-means requires more time for brain tumor detection compared to other methods like hierarchical clustering or K-means. It also reviews related work applying these clustering algorithms to segment brain MRI images.
1) The document simulates and compares the performance of AODV and DSDV routing protocols in a mobile ad hoc network under three conditions: when users are fixed, when users move towards the base station, and when users move away from the base station.
2) The results show that both protocols have higher packet delivery and lower packet loss when users are either fixed or moving towards the base station, since signal strength is better in those scenarios. Performance degrades when users move away from the base station due to weaker signals.
3) AODV generally has better performance than DSDV, with higher throughput and packet delivery rates observed across the different user mobility conditions.
This document describes the design and implementation of 4-bit QPSK and 256-bit QAM modulation techniques using MATLAB. It compares the two techniques based on SNR, BER, and efficiency. The key steps of implementing each technique in MATLAB are outlined, including generating random bits, modulation, adding noise, and measuring BER. Simulation results show scatter plots and eye diagrams of the modulated signals. A table compares the results, showing that 256-bit QAM provides better performance than 4-bit QPSK. The document concludes that QAM modulation is more effective for digital transmission systems.
The document proposes a hybrid technique using Anisotropic Scale Invariant Feature Transform (A-SIFT) and Robust Ensemble Support Vector Machine (RESVM) to accurately identify faces in images. A-SIFT improves upon traditional SIFT by applying anisotropic scaling to extract richer directional keypoints. Keypoints are processed with RESVM and hypothesis testing to increase accuracy above 95% by repeatedly reprocessing images until the threshold is met. The technique was tested on similar and different facial images and achieved better results than SIFT in retrieval time and reduced keypoints.
This document studies the effects of dielectric superstrate thickness on microstrip patch antenna parameters. Three types of probes-fed patch antennas (rectangular, circular, and square) were designed to operate at 2.4 GHz using Arlondiclad 880 substrate. The antennas were tested with and without an Arlondiclad 880 superstrate of varying thicknesses. It was found that adding a superstrate slightly degraded performance by lowering the resonant frequency and increasing return loss and VSWR, while decreasing bandwidth and gain. Specifically, increasing the superstrate thickness or dielectric constant resulted in greater changes to the antenna parameters.
This document describes a wireless environment monitoring system that utilizes soil energy as a sustainable power source for wireless sensors. The system uses a microbial fuel cell to generate electricity from the microbial activity in soil. Two microbial fuel cells were created using different soil types and various additives to produce different current and voltage outputs. An electronic circuit was designed on a printed circuit board with components like a microcontroller and ZigBee transceiver. Sensors for temperature and humidity were connected to the circuit to monitor the environment wirelessly. The system provides a low-cost way to power remote sensors without needing battery replacement and avoids the high costs of wiring a power source.
1) The document proposes a model for a frequency tunable inverted-F antenna that uses ferrite material.
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2. Understanding how this integration enhances test automation within the UiPath platform
3. Practical demonstrations
4. Exploration of real-world use cases illustrating the benefits of AI-driven test automation for UiPath
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What is generative AI
Test Automation with generative AI and Open AI.
UiPath integration with generative AI
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1. IOSR Journal of Electronics and Communication Engineering (IOSR-JECE)
e-ISSN: 2278-2834,p- ISSN: 2278-8735.Volume 10, Issue 4, Ver. III (Jul - Aug .2015), PP 60-69
www.iosrjournals.org
DOI: 10.9790/2834-10436069 www.iosrjournals.org 60 | Page
.
Application of Cell Zooming in Outage Compensation
S. N. Manegene1
*, S. Musyoki2
and P. K. Langat3
1,2,3
Jomo Kenyatta University of Agriculture and Technology (JKUAT),
Department of Telecommunication and Information Engineering
Abstract: The introduction of mobile communication has changed how people behave and their demand for
connectivity is anywhere and anytime. This demand is driven by the fact that essential services have moved from
mere telecommunication to very crucial services like money transfer services, e-learning and medical services.
However, terrorism threats, vandalism, environmental disasters and general failures are also on the increase
and these threaten the availability of mobile services anytime and everywhere. It is thus critical that measures
are taken to ensure availability of service amid these threats. Cell zooming promises to provide a self-healing
solution that would ensure the demand for service is anytime and anywhere is sustained. This paper investigates
the application of cell zooming in outage compensation. Cell zooming is achieved by adjusting the input power
to the transmitter or the height of the transmitter. The study developed an algorithm based on Okumura-Hata
propagation model to estimate the required height or power input to the transmitting antenna needed for the
compensation. The results are fed to Atoll Planning Software by Forsk to simulate the Received signal levels
pattern. The results have revealed that it is possible to achieve outage compensation using cell zooming. This is
in line with the proposal by Third Generation Partnership Project (3GPP) to have self-organising networks
(SONs) that require minimum human intervention for their operation.
Keywords: Cell Zooming, Outage compensation, Self-Healing, Self-Organizing Networks (SON), Radio
Network Planning, Mobile Traffic Analysis, Erlang B
I. Introduction
Cell outage is the total loss of service from a serving radio station as a result of a radio link failure.
These failures can be caused by a disruptive event such as power failure, equipment failure, and communication
breakdown with other elements in the network or a traffic surge that shuts down the cell through overload
protection mechanism. The main aim of a self-healing network is to promptly reduce the impact of the failure as
much as possible [1]. The network should be able to respond quickly so that as soon as fault is detected and its
impact quantified, compensation is introduced. The speed at which this should be implemented means that the
compensation cannot be done manually and hence the need for automation. The first step involves the effort to
mitigate the problem by means within the radio equipment itself but when there is a complete cell outage, this is
not possible and the compensation has to be done by the neighbouring cells [2], [3].
During compensation using neighbouring cells, a tradeoff between capacity and coverage is made in
order to alleviate the impact as much as possible. Optimization must also be done in order to maintain the
affected cells within the planning parameter range [4], [5], [6].
Link Budget, Path Loss and Propagation Models
The performance of a communication link depends on the quality of the transmit power, transmitting
antenna gain, and receiving antenna gain. In between the transmitting and receiving antenna, the signal gets
attenuated and this attenuation is the path loss. Thus path loss is the attenuation of the power density of an
electromagnetic wave as it travels through space. Link budgeting is used to account for all the losses and gains
in the link to ensure that acceptable signal level is received for effective communication.
To determine path loss, transmitter output is first evaluated. Transmitter output is boosted by system
antenna gain and reduced by transmission line and connector losses. Link budget can be summarized in equation
(1) below
PT– TL + GT– PL + GR + RL = RS (2)
Where
PT = transmitter power
TL= Transmitter cable and connector losses
GT = Gain of transmitter
PL = Path loss
GR =Gain of receiver
RL = Receiver cable and connector losses
RS =Receiver power
2. Application of Cell Zooming in Outage Compensation...
DOI: 10.9790/2834-10436069 www.iosrjournals.org 61 | Page
Effective Isotropic Radiated Power (EIRP) is given by:
EIRP = PT– TL + GT (3)
wherethe above definitions apply.
When the power transmitted by the antenna minus all the losses is greater than the minimum allowed signal
levelof the receiving antenna, then communication is possible between the two radios. However, it is prudent to
add margin to the minimum allowed received levels for a more reliable link.
PT– TL + GT– PL + GR + RL = RS + Margin (4)
Rewriting this equation yields
PT– TL + GT– PL = RS − GR + RL + Margin (5)
but
RSSI = RS − GR + RL (6)
Where RSSI is the received signal strength indicator.
It is thus noted
EIRP = MAPL + RSSI + Margin (7)
Where MAPL is the maximum allowable path loss.
A number of empirical propagation models have been proposed that help in predicting path loss and
propagation pattern but for the purpose of this investigation, only Okumura-Hata Model was considered.
Okumura-Hata Model
In this model, Path Loss is given by [7],
PL = A + B log(d) + C (8)
where A, B, and C are factors that depend on frequency and antenna height.
𝐴 = 69.55 + 26.16 𝑙𝑜𝑔 𝑓𝑐 − 13.82 𝑙𝑜𝑔 𝑏 − 𝑎 𝑚 (9)
𝐵 = 44.9 − 6.55 𝑙𝑜𝑔( 𝑏 ) (10)
Where
𝑓𝑐 = frequency in MHz
d = distance in km
hb= height of base station in meters
The function 𝑎 𝑚 and the factor C depend on the environment:
For small and medium-size cities:
𝑎 𝑚 = 1.1 𝑙𝑜𝑔 𝑓𝑐 − 0.7 𝑚 − (1.56 𝑙𝑜𝑔(𝑓𝑐) − 0.8) (11)
C = 0
For metropolitan areas:
𝑎(𝑚 ) = 3.2(𝑙𝑜𝑔(11.75 𝑚 )2
− 4.97 (12)
C = 0
For suburban environments:
𝐶 = −2 𝑙𝑜𝑔
𝑓𝑐
28
2
− 5.4 (13)
For rural areas
𝐶 = −4.78 𝑙𝑜𝑔 𝑓𝑐
2
+ 18.33𝑙𝑜𝑔𝑓𝑐 − 40.98 (14)
The function 𝑎 𝑚 in suburban and rural areas is the same as given in equation (10)
1. Outage Compensation Using Cell Zooming
One of the methods that can be used automatically for outage compensation is cell zooming. Cell
zooming is the adjustment of the cell size by varying electrical power dissipated by the antenna or by varying
the tilt angle of the antenna either by mechanical or electrical means [8], [9] or by varying the height of the
antenna.
Electrical Zooming
For a specific region, path loss is dependent on frequency and distance. Thus at fixed frequency, path
loss will be dependent only on distance. Consequently, increasing the radiated power means there is a net
margin to allow for a longer distance. Similarly, reducing the power would lower the overall distance that the
acceptable signal can cover. This is the electrical zooming. It is achieved by varying the power fed to the
transmitting antenna to vary the coverage radius.
Height adjustment
Figure 1 summarizes the effects of varying the height of the transmitter on the coverage distance. The
higher the antenna, the longer the possible coverage distance
3. Application of Cell Zooming in Outage Compensation...
DOI: 10.9790/2834-10436069 www.iosrjournals.org 62 | Page
Figure 1: Path Loss for Different Transmitter Heights
2. Factors Affecting Compensation Using Cell Zooming
Received Signal Levels
A coverage area is a region within which the received signal level is within acceptable limit of -105dB.
This is the minimum power required by the Mobile Station (MS) to sustain a communication between the radio
and the MS and a minimum power of -114dBm is required to be received at the Base Transceiver Station (BTS)
antenna to sustain communication with a MS [10]. The received levels are recommended as In-car=-100dBm,
Indoor=-95dBm and Outdoor=-105dBm [11].
Capacity
This is the size of available resources for carrying traffic. Usually, the limiting capacity is that of traffic
channels (TCH). The other channels on a radio hardly get congested except in a case of extreme traffic or as a
result of equipment fault.
The size of traffic channels is calculated using Erlang B calculator or read from traffic tables. These
tables give the number of traffic channels (trunks) required to sustain a given traffic at a given probability of
blocking. Blocking probability is referred to as Grade of Service (GoS). Capacity issues can be addressed by
using the following methods:
Multi Radio Access Technology (Multi-Rat)
This is where one site is served by multiple radios of different radio technologies with each of the radio
technology being independent of the other. These technologies include GSM at 900 MHz, GSM at 1800MHz
and UMTS (3G) at 2100MHz. Introduction of 3G on 900MHz is in initial stages. It is common to have these
technologies on the same site together. This is termed as a technology collocation [5]. These two technologies
work simultaneously but in the event one fails the other takes over all the traffic. However, while a 3G phone
can operate on 2G environment, the converse is not true. At the same time, the quality of data service is greatly
affected when a 3G subscriber downgrades to use 2G technology. Again, when it’s the 2G feed that fails, then
the 2G users who do not have 3G capable handsets are put out of service. More so, the amount of traffic that can
be carried by one technology is limited during planning since planning is done with the consideration that the
two technologies work on complementary basis and not as a substitute of each other [4].
Adaptive Multi Rate-Half Rate (Amr-Hr)
A standard voice encoding is at 16Kbps at the radio level. Any encoding method reducing the bit-rate
to 8kbps or less is the half rate. This doubles the available capacity but compromises on the speech (voice)
quality. To set a balance between capacity and quality, the half rate is normally introduced when a particular
capacity threshold is reached and is only allowed in areas whose speech quality will not be greatly
compromised. For example, areas where low signal strength is already compromising sound quality should not
be candidate for half rate. The AMR codec provides operators with a means to optimize the balance between
voice quality and spectral efficiency by continuously selecting the optimal speech codec rate for the current
radio and traffic conditions.
The AMR codec provides radio link adaptation in difficult Radio Frequency (RF) environments by an
optimal combination of speech and error-correcting channel coding. AMR-HR uses lowest codec rates in good
RF conditions to maximize on coverage and spectrum utilization and dynamically changes to higher codec rates
when the RF conditions are poor at the compromise of capacity and spectral efficiency [12].
4. Application of Cell Zooming in Outage Compensation...
DOI: 10.9790/2834-10436069 www.iosrjournals.org 63 | Page
Dynamic channel allocation
Traffic channels are either configured as voice or data channels in GSM. Some of the channels can be
configured as dual channels and these are capable of both voice and data. Dynamic adjustment can be made
either to increase the allocation for voice or data, depending on which traffic type is high. Usually, voice is
given priority over data with the potential of dropping a data call in order to service a voice call in the event
there are no channels to service it [13].
Cow
Cell on Wheel is a cellular radio that is normally mounted on a movable container, which is transported
on road or by air to a location, which has no coverage or has gone out of coverage and restoration of service
would take long to be effected. This method is especially useful in a disaster scenario and in areas where high
traffic is anticipated because of a certain event such as public rallies.
Subscriber Calling Pattern
The goal of every cellular network planning team is to strike a balance between coverage and capacity.
There are two aspects of coverage. One looks at the number of subscribers covered while the second is the
geographical region. The end product is the volume of traffic generated in an area. In areas where the call
density is high, the available capacity has to be adjusted to meet this demand. This leads to two types of
planning: one in which major consideration is coverage especially in rural (sparsely populated) areas and the
second one, which concentrates on providing capacity in dense traffic urban region.
The density of calls is what determines the volume of traffic rather than the number of subscribers. We
could have a region with few subscribers that call very frequently and for long. This determines the density of
radios that are installed in a region. This is because there is a limitation on the number of calls a radio can
accommodate in an instant.
II. Compensation Process
The key requirement in compensation was to establish the compensation parameters by solving the
Okumura-Hata path loss equations. This solves for the maximum allowable path loss and hence the coverage
distance.
Solving For Coverage Distance
𝐏𝐋 − 𝐀 − 𝐂 = 𝐁 𝐥𝐨𝐠(𝐝) (15)
d = antilog
PL− A−C
B
(16)
From and using equation (17) maximum allowable distance was calculated as follows
Equation (18)was used to calculate the coverage radius for specific path loss.
Substituting the values of A, B and C as given on 61 gives
d = antilog(
PL−69.55 + (26.16 ∗ log (fc ) ) − (13.82 ∗ log hb −a(hm ))
44.9−6.55 log (hb )
)
(19)
Solving for Base Station height
From the equation PL = A + B log(d) + C (8(20)
Let B log(d) = G
Therefore PL = A + G + C
Solving equation (21) for hbgives
𝐡 𝐛 = 𝐚𝐧𝐭𝐢𝐥𝐨𝐠
𝟔𝟗.𝟓𝟓+𝟐𝟔.𝟏𝟔 𝐥𝐨𝐠 𝐟 𝐜 −𝐚 𝐡 𝐦 +𝟒𝟒.𝟗𝐥𝐨𝐠 𝐝 –𝐏𝐋
𝟏𝟑.𝟖𝟐+𝟔.𝟓𝟓 𝐥𝐨𝐠 𝐝
(22)
Therefore, for known values of Maximum Allowable Path Loss and coverage distance, the required height of
the base station can be evaluated using this formula.
Solving for transmit power
We knowEIRP = MAPL + RSSI
Target RSSI is set and for a specific distance. MAPL can be calculated as already shown.
5. Application of Cell Zooming in Outage Compensation...
DOI: 10.9790/2834-10436069 www.iosrjournals.org 64 | Page
III. Simulations and Results
Three simulations were carried out for different complexity. Two of them were completely experimental while
the third used data from an existing installation.
Experimental Network Cluster
This considers two clusters: One cluster which has even distribution of cells in the cluster, all antennas
are at the same height, the traffic is evenly distributed, the cells are of equal capacity and the terrain is ideal –
homogenous cluster. The second cluster has even distribution of cells but the radiated power and antenna height
are varied –non homogenous cluster.
During compensation of a 3 sectored cell the compensation distance is 1.5 times the healthy distance. The data
on Table 1, Table2 and
Table 3were used for compensation and the signal level patterns generated are on Figure 2 to Figure 4 below.
Table 1: Simulation parameters
PARAMETER VALUE
Target RSSI -90dBm
MAPL 150dB
Mobile station antenna height
(hm)
1 m
Frequency (fMHz) 900
Propagation Model Okumura-Hata (Medium & small city)
Table2: Compensation values for Homogenous Configuration
Before
compensation
Compensation
by height
Compensation
by EIRP
Antenna
height
35m 63.9m 35m
EIRP 60dBm 60dBm 65.1dBm
Distance 4.66km 6.99km 6.99km
Table 3: Compensation values for Non-Homogenous Configuration
Before
compensation
Compensation by
height
Compensation by
EIRP
EIRP hb EIRP hb EIRP hb
A 60 35 60 35 60 35
B 61.7 25 61.7 52.3 68 25
C 57.9 40 57.9 81.8 64 40
D 60 35 60 35 60 35
E 60 35 60 35 60 35
F 60 35 60 35 60 35
G 55.4 55 55.4 109.8 61.3 55
Distance
4.66km 6.99km 6.99km
The compensation parameters on Table2 and
Table 3 were calculated using equation (5) and (17) and the distance using equation (16)
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Figure 2: Coverage by Signal Level for a healthy 3 sectored cluster
When the network is simulated with the 7 cells such that the coverage distance is exact separation
distance between the cells, it was observed that small pockets with unacceptable signal levels are generated
around the central cell. These are however acceptable compromise.
Figure 3: Coverage by Signal Level for a homogenous single sectored cluster after Cell D is switched off
After Cell D is switched of as shown in Figure 3 the area that was covered by cell D is left with signal
level below acceptable RSSI. The compensation yields the pattern in Figure 4 again with some small pockets of
signal below the acceptable signal level.
Figure 4: Coverage by Signal Level for a homogenous 3 sectored cluster after Cell D is switched off but with
compensation using cells B, C & G
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Figure 5: Signal levels definition
The signal level distribution pattern in Figure 2 to Figure 4 applies to both the homogenous and non
homogenous simulation. This was the case because the coverage area was equal for both clusters.
Simulation Using Data Obtained From A Live Network
Data for 17 cells from an existing network (safaricom) was used to generate the coverage on
Figure 6 with the RSSI restricted to -90dBm. Two areas were identified as region A and B. The signal
level available in region A is still acceptable even after a target cell failed as shown in Figure 7 and Figure 8.
Figure 6: Signal Level of Cells of an existing network -90dBm RSSI
Figure 7: Close up for region A when healthy
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Figure 8: Region A with Cell EC0256 failed
Figure 9: close-up for healthy region B
Figure 9is an example of an area with a relatively low density of radios. When cell EC0004 fails, as
shown in Figure 10,a significant area, which was under the cell coverage is left with signal below the target
RSSI necessitating compensation. Two cells were selected for compensation. Cell EC0321 sector 3, which is at
an azimuth of 290 and cell EC0255 sector 1 at 0 azimuth.
Figure 10: Close-up for region B with cell EC0004 Failed
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The power was increased for the two sectors from 57.3dBm to 62dBm EIRP and the azimuths changed
from 290 to 270 and 0 to 30 respectively. This gave an acceptable compensation for the received signal level.
However, use of only two sectors to compensate gives a huge load to the compensating cells. A huge reserve
capacity will be required in the compensating cells in order to accommodate for the load. Nevertheless, it is not
uncommon to have some cells that are of small capacity and their compensation can be adequately taken over by
just one big cell. Figure 11 demonstrates this compensation.
Figure 11: Region B after compensation for cell EC0004
IV. Conclusions
In this work a self-healing radio network was simulated with different complexity levels which shows
that it is possible to implement this kind of network in real network. Simulation using data from actual network
was included and this also agreed with theory.
The study shows how self healing can be implemented by introducing compensation through cell
zooming. Two methods of self healing including height adjustment and power adjustment were considered and
these gave good results. Since the simulator that was used from Atoll is very popular in the telecommunication
industries, then the results obtained are representative of real network situation.
However, in order to handle the extra traffic that results from the failed cells during the busy period, the
study suggests provision of some extra (reserve) capacity that should be calculated on an individual cell basis
proportional to the traffic in the cluster. Other suitable methods of ensuring capacity is adequate include use of
dynamic channel allocation. Though this does not exactly increase the trunk size, it would help in relieving the
traffic level by prioritizing on requirement. Though AMR-HR is very good, it may at times introduce quality
degradation. This may however be accepted considering any network optimization goal is to balance all factors
for best results.
The study also revealed that a real network can be categorized into two regions according to the density
of antennas. The much cluttered regions have high received signal levels and compensation should focus on
additional capacity on the trunks. In a scattered area, the compensation can be achieved through neigbouring
cells. However, consideration of power and height adjustment alone did not provide an optimal relief. It is
important to consider the element of azimuth as it proved a major player both to the success of the compensation
as well as for maintaining the health of the unaffected cells.
It is worth noting that, however, for cell zooming compensation method to maintain optimal
characteristics, its various factors in Height, Electrical and Mechanical tilts and Power Levels must be well
matched.
Acknowledgement
We wish to thank the staff of Safaricom limited who through their generosity and advice, we have been
able to progress this research to conclusion.
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