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.
Signal Strength Evaluation of a 3G Network in Owerri Metropolis Using Path Lo...Onyebuchi nosiri
Abstract: In this work, the path loss and the received signal strength of a 3G network at 2.1GHz was evaluated to determine its performance within the Owerri metropolis. Various measuring equipment such as Transmission Evaluation and Monitoring System (TEMS 11), Global positioning system (BU353 GPS) and laptop were deployed for the drive test within the selected urban and sub-urban regions. From the data collected, Owerri sub-urban region showed poor received signal power level compared to the Owerri urban region. The path loss exponents computed for the Owerri urban and sub-urban regions are 3.24 and 4.34 respectively, the mean square error was evaluated as 1.96 and 1.68. The result obtained showed deviations between the compared existing models (Hata and Cost 231) and the proposed models. However, the slope of the Hata plot was relatively close in comparison to the proposed model than that of Cost 231; hence, the proposed model was best suited for the environment followed by the Hata model.
Implementation of Particle Swarm Optimization Technique for Enhanced Outdoor ...Onyebuchi nosiri
This paper describes the development of optimized model for urban outdoor coverage in Long Term Evolution (LTE) network at 2300 MHz frequency band in Port Harcourt urban region, Nigeria. Signal attenuation and fluctuation remain amongst the major channel impairments for mobile radio communication systems. This arises as a result of model incompatibility with terrain and Line of Sight (LOS) obstruction of the channel signals. Some path loss models such as OkumuraHata, COST 231, Ericsson 999, Egli and ECC-33 models were evaluated for suitability and compared with the modified model for the environments. The models were based on data collected from LTE base stations at three geographical locations in Port Harcourt namely- Rumuokoro, Eneka and Ikwerre roads respectively. The simulation was implemented using MATLAB R2014a software. The modified model was further optimized with some selected parameters such as Root Mean Square Error (RMSE) and Mean Absolute Error (MAE) using Particle Swarm Optimization (PSO) technique. The results obtained gave rise to 3.030dB for RMSE and 0.00162dB for MAE respectively. The results obtained from the PSO optimized model demonstrated a better performance which is suitable for cell coverage planning and smooth handoff processes.
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
Signal Strength Evaluation of a 3G Network in Owerri Metropolis Using Path Lo...Onyebuchi nosiri
Abstract: In this work, the path loss and the received signal strength of a 3G network at 2.1GHz was evaluated to determine its performance within the Owerri metropolis. Various measuring equipment such as Transmission Evaluation and Monitoring System (TEMS 11), Global positioning system (BU353 GPS) and laptop were deployed for the drive test within the selected urban and sub-urban regions. From the data collected, Owerri sub-urban region showed poor received signal power level compared to the Owerri urban region. The path loss exponents computed for the Owerri urban and sub-urban regions are 3.24 and 4.34 respectively, the mean square error was evaluated as 1.96 and 1.68. The result obtained showed deviations between the compared existing models (Hata and Cost 231) and the proposed models. However, the slope of the Hata plot was relatively close in comparison to the proposed model than that of Cost 231; hence, the proposed model was best suited for the environment followed by the Hata model.
Implementation of Particle Swarm Optimization Technique for Enhanced Outdoor ...Onyebuchi nosiri
This paper describes the development of optimized model for urban outdoor coverage in Long Term Evolution (LTE) network at 2300 MHz frequency band in Port Harcourt urban region, Nigeria. Signal attenuation and fluctuation remain amongst the major channel impairments for mobile radio communication systems. This arises as a result of model incompatibility with terrain and Line of Sight (LOS) obstruction of the channel signals. Some path loss models such as OkumuraHata, COST 231, Ericsson 999, Egli and ECC-33 models were evaluated for suitability and compared with the modified model for the environments. The models were based on data collected from LTE base stations at three geographical locations in Port Harcourt namely- Rumuokoro, Eneka and Ikwerre roads respectively. The simulation was implemented using MATLAB R2014a software. The modified model was further optimized with some selected parameters such as Root Mean Square Error (RMSE) and Mean Absolute Error (MAE) using Particle Swarm Optimization (PSO) technique. The results obtained gave rise to 3.030dB for RMSE and 0.00162dB for MAE respectively. The results obtained from the PSO optimized model demonstrated a better performance which is suitable for cell coverage planning and smooth handoff processes.
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
Validation study of path loss models onijngnjournal
The radio wave propagation in form of path loss model plays very significant role in planning of any
wireless communication network. Measurement of signal strength of OFDM driven WiMAX technology at
2.6 GHz band is taken in Suburban Town of India. The results are analyzed and compared with Empirical
path loss models such as Hata-Okumura, Modified Hata and COST-231Hata. COST-231 model shows
highest path loss for suburban environment. These analyzed results establish that COST-231 model is
suitable for suburban environment also. Threshold RSSI estimates cell coverage probability in the area.
Path Loss Characterization of 3G Wireless Signal for Urban and Suburban Envir...Onyebuchi nosiri
Abstract - The characteristic effects of propagation environment on wireless communication signals are significant on the transmitted and received signal quality. The study focused on investigative analysis of the effects of propagation environment on the wireless communication signals within some geographical domains in Port Harcourt, River State. Field measurements were carried out in some selected areas namely GRA phase II and Aggrey Road categorized as urban and Sub urban areas respectively using Sony Ericsson (W995) Test Phone and GPS receiver (BU353). The analyses were based on linear regression (mean square error) approach. The computed path loss exponents and standard deviation based on the empirical analyses conducted for urban and suburban environments are 3.57dB, 2.98dB and 19.6, 13.2, respectively. The results obtained were used to compare the performance of the various existing path loss prediction models such as Okumura-Hata, Cost 231 and ECC-33. Okumura-Hata model showed better performance in urban environment while Cost 231 performed better in rural environment. They study therefore recommends the deployment of Okumura-Hata model in urban, while Cost 231for suburban study areas.
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.
IMPROVED PROPAGATION MODELS FOR LTE PATH LOSS PREDICTION IN URBAN & SUBURBAN ...ijwmn
To maximize the benefits of LTE cellular networks, careful and proper planning is needed. This requires the use of accurate propagation models to quantify the path loss required for base station deployment. Deployed LTE networks in Ghana can barely meet the desired 100Mbps throughput leading to customer dissatisfaction. Network operators rely on transmission planning tools designed for generalized environments that come with already embedded propagation models suited to other environments. A challenge therefore to Ghanaian transmission Network planners will be choosing an accurate and precise propagation model that best suits the Ghanaian environment. Given this, extensive LTE path loss measurements at 800MHz and 2600MHz were taken in selected urban and suburban environments in Ghana and compared with 6 commonly used propagation models. Improved versions of the Ericson, SUI, and ECC-33 developed in this study predict more precisely the path loss in Ghanaian environments compared with commonly used propagation models.
ADAPTIVE RANDOM SPATIAL BASED CHANNEL ESTIMATION (ARSCE) FOR MILLIMETER WAVE ...IJCNCJournal
Millimeter-wave and mMIMO communications are the most essential success systems for next-generation wireless sensor networks to have enormous amounts of accessible throughput and spectrum. Through installing huge antenna arrays at the base station and performing coherent transceiver processing, mMIMO is a potential technology for enhancing the bandwidth efficiency of wireless sensor networks. The use of mmWave frequencies for mMIMO systems solves the problem of high path-loss through offering greater antenna gains. In this work, we provide a design with a random spatial sample structure that incorporates a totally random step before the analogue is received. It contains a totally random step before the analogue received signals are sent into the digital component of the HBF receiver. Adaptive random spatial based channel estimation (ARSCE) is proposed for channel session measurement collection, and an analogue combiner with valves has been used to estimate the signals at each receiving antenna. The proposed optimization problem formulation attempts to discover the orientations and gains of wideband channel routes. In addition, our proposed model has compared to various state-of-art techniques while considering error minimization.
Outage performance users located outside D2D coverage area in downlink cellul...journalBEEI
Device-to-device (D2D) communication has been proposed to employ the proximity between two devices to enhance the overall spectrum utilization of a crowded cellular network. With the help of geometric probability tools, this framework considers the performance of cellular users under spatial separation with the D2D pair is investigated. The measurement results and analytical expression of outage probability show that the proposed frameworks improve the outage performance at a high signal-tonoise ratio (SNR) at the base station. Results also interpret that the distances between nodes in the D2D-assisted network make slight impacts on the performance of the cellular user.
IOSR Journal of Humanities and Social Science is an International Journal edited by International Organization of Scientific Research (IOSR).The Journal provides a common forum where all aspects of humanities and social sciences are presented. IOSR-JHSS publishes original papers, review papers, conceptual framework, analytical and simulation models, case studies, empirical research, technical notes etc.
Determination of load transfer in reinforced concrete solid slabs by finite e...IOSR Journals
According to the ACI building code, the concrete slab can be divided into two types depending on
the ratio of the long side to the short side. Regarding the results of the ratio, the concrete slab can be divided as
one-way and two-way slabs. The main objective of this paper is to study the stress or moments distribution in
solid slab panel in its two directions and compare with ACI code assumption that the load is transferred mainly
in short direction and most of the load is transferred in one direction only if the ratio of the longer span to the
shorter span is greater than one. This will be discussed by analyzing one panel of solid slab using the computer
software SAP2000. Two types of panels will be used; the first one a panel that is supported simply on its four
sides and the second panel is supported only by four pin supports and beams. This paper shows that the gravity
load on the slab is transferred to long and short direction. This means that one-way concrete solid slab doesn't
exist and all concrete solid slabs work as a two-way concrete slab.
Validation study of path loss models onijngnjournal
The radio wave propagation in form of path loss model plays very significant role in planning of any
wireless communication network. Measurement of signal strength of OFDM driven WiMAX technology at
2.6 GHz band is taken in Suburban Town of India. The results are analyzed and compared with Empirical
path loss models such as Hata-Okumura, Modified Hata and COST-231Hata. COST-231 model shows
highest path loss for suburban environment. These analyzed results establish that COST-231 model is
suitable for suburban environment also. Threshold RSSI estimates cell coverage probability in the area.
Path Loss Characterization of 3G Wireless Signal for Urban and Suburban Envir...Onyebuchi nosiri
Abstract - The characteristic effects of propagation environment on wireless communication signals are significant on the transmitted and received signal quality. The study focused on investigative analysis of the effects of propagation environment on the wireless communication signals within some geographical domains in Port Harcourt, River State. Field measurements were carried out in some selected areas namely GRA phase II and Aggrey Road categorized as urban and Sub urban areas respectively using Sony Ericsson (W995) Test Phone and GPS receiver (BU353). The analyses were based on linear regression (mean square error) approach. The computed path loss exponents and standard deviation based on the empirical analyses conducted for urban and suburban environments are 3.57dB, 2.98dB and 19.6, 13.2, respectively. The results obtained were used to compare the performance of the various existing path loss prediction models such as Okumura-Hata, Cost 231 and ECC-33. Okumura-Hata model showed better performance in urban environment while Cost 231 performed better in rural environment. They study therefore recommends the deployment of Okumura-Hata model in urban, while Cost 231for suburban study areas.
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.
IMPROVED PROPAGATION MODELS FOR LTE PATH LOSS PREDICTION IN URBAN & SUBURBAN ...ijwmn
To maximize the benefits of LTE cellular networks, careful and proper planning is needed. This requires the use of accurate propagation models to quantify the path loss required for base station deployment. Deployed LTE networks in Ghana can barely meet the desired 100Mbps throughput leading to customer dissatisfaction. Network operators rely on transmission planning tools designed for generalized environments that come with already embedded propagation models suited to other environments. A challenge therefore to Ghanaian transmission Network planners will be choosing an accurate and precise propagation model that best suits the Ghanaian environment. Given this, extensive LTE path loss measurements at 800MHz and 2600MHz were taken in selected urban and suburban environments in Ghana and compared with 6 commonly used propagation models. Improved versions of the Ericson, SUI, and ECC-33 developed in this study predict more precisely the path loss in Ghanaian environments compared with commonly used propagation models.
ADAPTIVE RANDOM SPATIAL BASED CHANNEL ESTIMATION (ARSCE) FOR MILLIMETER WAVE ...IJCNCJournal
Millimeter-wave and mMIMO communications are the most essential success systems for next-generation wireless sensor networks to have enormous amounts of accessible throughput and spectrum. Through installing huge antenna arrays at the base station and performing coherent transceiver processing, mMIMO is a potential technology for enhancing the bandwidth efficiency of wireless sensor networks. The use of mmWave frequencies for mMIMO systems solves the problem of high path-loss through offering greater antenna gains. In this work, we provide a design with a random spatial sample structure that incorporates a totally random step before the analogue is received. It contains a totally random step before the analogue received signals are sent into the digital component of the HBF receiver. Adaptive random spatial based channel estimation (ARSCE) is proposed for channel session measurement collection, and an analogue combiner with valves has been used to estimate the signals at each receiving antenna. The proposed optimization problem formulation attempts to discover the orientations and gains of wideband channel routes. In addition, our proposed model has compared to various state-of-art techniques while considering error minimization.
Outage performance users located outside D2D coverage area in downlink cellul...journalBEEI
Device-to-device (D2D) communication has been proposed to employ the proximity between two devices to enhance the overall spectrum utilization of a crowded cellular network. With the help of geometric probability tools, this framework considers the performance of cellular users under spatial separation with the D2D pair is investigated. The measurement results and analytical expression of outage probability show that the proposed frameworks improve the outage performance at a high signal-tonoise ratio (SNR) at the base station. Results also interpret that the distances between nodes in the D2D-assisted network make slight impacts on the performance of the cellular user.
IOSR Journal of Humanities and Social Science is an International Journal edited by International Organization of Scientific Research (IOSR).The Journal provides a common forum where all aspects of humanities and social sciences are presented. IOSR-JHSS publishes original papers, review papers, conceptual framework, analytical and simulation models, case studies, empirical research, technical notes etc.
Determination of load transfer in reinforced concrete solid slabs by finite e...IOSR Journals
According to the ACI building code, the concrete slab can be divided into two types depending on
the ratio of the long side to the short side. Regarding the results of the ratio, the concrete slab can be divided as
one-way and two-way slabs. The main objective of this paper is to study the stress or moments distribution in
solid slab panel in its two directions and compare with ACI code assumption that the load is transferred mainly
in short direction and most of the load is transferred in one direction only if the ratio of the longer span to the
shorter span is greater than one. This will be discussed by analyzing one panel of solid slab using the computer
software SAP2000. Two types of panels will be used; the first one a panel that is supported simply on its four
sides and the second panel is supported only by four pin supports and beams. This paper shows that the gravity
load on the slab is transferred to long and short direction. This means that one-way concrete solid slab doesn't
exist and all concrete solid slabs work as a two-way concrete slab.
Peak to Average Power Ratio Performance of a 16-QAM/OFDM System with Partial ...IOSR Journals
Abstract : Orthogonal Frequency Division Multiplexing is a spectral efficient transmission format. But it suffers from the problem of high Peak to Average Power Ratio. This high Peak to Average Power Ratio leads the power amplifier into saturation and results in non-linear distortion at the output of power amplifier. Different peak to average power ratio reduction techniques are available in literature. This paper computes the performance of partial transmit scheme, which is one of the important peak to average power ratio reduction technique Keywords: Orthogonal Frequency Division Multiplexing, Partial Transmit Sequence, Peak to Average Power Ratio, Power Amplifier, Scrambling Techniques.
Design analysis and Commissioning Of High Mast Lighting PolesIOSR Journals
Along a major highway, luminaire pole structures may be seen every 101 of a mile.From documented
cases, it appears that these structures started to experience fatigue problems in the last three decades. The
general public might not be aware of the problem, because if such a failure occurs, the structure is replaced.
Those working in the fatigue area realize that this issue is a serious matter[15][16]. Clearly, the damage is
costly, costing up to thousands of dollars per occurrence. For this purpose, a high mast lighting poles are
fabricated using steel due to its high strength, ductilityproperty and wear resistance. The high mast structure
(HMS) has the characters of light weight and high cost efficiency. It possess large ratio of height (H) to least
horizontal dimension (D) that makes it more slender and wind-sensitive than any other structures[17].
Therefore, the purpose of this research is to design optimal high mast poles taking into account its specification,
environmental conditions for placement and economy. Initially, among various pole designs, the high mast pole
is considered to be in tapered section as it is more reliable and economical. Then, analysis is performed in solid
works by keeping the base section to be fixed and applying compressive load on the top section of the pole due
to heavy weight of cantilever mast arm and luminaire. This project illustrates the theoretical basis and the
analytical development of the high mast lighting poles
Signal Strength Evaluation of a 3G Network in Owerri Metropolis Using Path Lo...Onyebuchi nosiri
Abstract: In this work, the path loss and the received signal strength of a 3G network at 2.1GHz was evaluated to determine its performance within the Owerri metropolis. Various measuring equipment such as Transmission Evaluation and Monitoring System (TEMS 11), Global positioning system (BU353 GPS) and laptop were deployed for the drive test within the selected urban and sub-urban regions. From the data collected, Owerri sub-urban region showed poor received signal power level compared to the Owerri urban region. The path loss exponents computed for the Owerri urban and sub-urban regions are 3.24 and 4.34 respectively, the mean square error was evaluated as 1.96 and 1.68. The result obtained showed deviations between the compared existing models (Hata and Cost 231) and the proposed models. However, the slope of the Hata plot was relatively close in comparison to the proposed model than that of Cost 231; hence, the proposed model was best suited for the environment followed by the Hata model.
Comparative Study of Path Loss Models for Wireless Communication in Urban and...Onyebuchi nosiri
ABSTRACT: The study was based on the comparative analysis of radio propagation models for Global System for Mobile Communications at 900MHz. Drive test analyses were carried out from two selected terrains in Rivers State namely GRA Phase II and Aggrey Road classified as urban and suburban areas respectively, to evaluate the best propagation model for the study area. The data obtained were used to compare the various prediction models namely; Cost 231, Okumura-Hata and ECC-33. Mean path loss values of 115.16dB for Okumura-Hata and 117.79dB for COST 231 and 280.88dB for ECC-33 respectively were predicted in the urban environment. Mean path loss values of 115.16dB, 114.76dB and 314.84dB were predicted by Okumura-Hata, Cost 231and ECC-33 models respectively in the suburban environment. ECC-33 over estimated path loss and gave the highest prediction in both environments. Okumura-Hata model showed better performance in urban while COST 231 performed better in the suburban environment. Okumura-hata and COST 231 models are recommended for deployment in urban and suburban environments respectively.
Abstract: While designing a cellular network, the main issue for the network planning is to achieve maximum
capacity while maintaining an acceptable grade of service and good speech quality. Planning an immature
network does not allow future growth and expansion. Wise & calculative re-use of site location in the future
network structure will save money for the operator. For this reason, digital maps are one of the most essential
elements to the network engineers while they have to think about expanding their business. However, the digital
maps cost a lot of money. This problem can be mitigated if Google Earth is used.
In this paper, the procedure of how to design a cellular digitized map on Google Earth is shown. By
calculating the cell radius, implementing the single cell site, forming the 7-cell cluster and all the cells a low
cost digitized map is designed. It is necessary to have a digitized map in mobile communication because
ultimate goal includes efficient usage of RF wave, frequency reuse, total use of BW and last but not the least
cost reduction.
Keywords: Cellular digitized map, Cell radius, Google Earth.
Validation Study of Path Loss Models on Wimax At 2.6 Ghz Frequency Band in Su...josephjonse
The radio wave propagation in form of path loss model plays very significant role in planning of any wireless communication network. Measurement of signal strength of OFDM driven WiMAX technology at 2.6 GHz band is taken in Suburban Town of India. The results are analyzed and compared with Empirical path loss models such as Hata-Okumura, Modified Hata and COST-231Hata. COST-231 model shows highest path loss for suburban environment. These analyzed results establish that COST-231 model is suitable for suburban environment also. Threshold RSSI estimates cell coverage probability in the area
COMPARISON OF RADIO PROPAGATION MODELS FOR LONG TERM EVOLUTION (LTE) NETWORKijngnjournal
This paper concerns about the radio propagation models used for the upcoming 4th Generation (4G) of cellular networks known as Long Term Evolution (LTE). The radio wave propagation model or path loss model plays a very significant role in planning of any wireless communication systems. In this paper, a comparison is made between different proposed radio propagation models that would be used for LTE, like Stanford University Interim (SUI) model, Okumura model, Hata COST 231 model, COST Walfisch-Ikegami & Ericsson 9999 model. The comparison is made using different terrains e.g. urban, suburban and rural area.SUI model shows the lowest path lost in all the terrains while COST 231 Hata model illustrates highest path loss in urban area and COST Walfisch-Ikegami model has highest path loss for suburban and rural environments.
An Analytical Analysis of Path Loss Models for Mobile Cellular Wireless Commu...IJCI JOURNAL
The paper deals with the study based on the comparative analysis of radio propagation models for mobile cellular wireless communication of global system for mobile at frequencies 0.9 GHz and 1.8 GHz,respectively. The path loss propagation models are vital tool for planning the wireless network as well as
designed to predict path loss in a meticulous environment. Various propagation models: Free-space model, CCIR (ITU-R) model, Hata model, Ericson model, and Stanford University Interim (SUI) model have been studied and examined through analytically from the base station (BS) to mobile station (MS)
and vice versa followed by respective simulation performance evaluation by using Matlab simulator. The observed data is collected at the operating frequency of 0.9 GHz from various environments (high density region and low density region) using the spectrum analyzer and path loss comparison is shown for
different model.
AN ANALYTICAL ANALYSIS OF PATH LOSS MODELS FOR MOBILE CELLULAR WIRELESS COMMU...IJCI JOURNAL
The paper deals with the study based on the comparative analysis of radio propagation models for mobile cellular wireless communication of global system for mobile at frequencies 0.9 GHz and 1.8 GHz, respectively. The path loss propagation models are vital tool for planning the wireless network as well as
designed to predict path loss in a meticulous environment. Various propagation models: Free-space model, CCIR (ITU-R) model, Hata model, Ericson model, and Stanford University Interim (SUI) model have been studied and examined through analytically from the base station (BS) to mobile station (MS)
and vice versa followed by respective simulation performance evaluation by using Matlab simulator. The observed data is collected at the operating frequency of 0.9 GHz from various environments (high density region and low density region) using the spectrum analyzer and path loss comparison is shown for
different model.
AN ANALYTICAL ANALYSIS OF PATH LOSS MODELS FOR MOBILE CELLULAR WIRELESS COMMU...IJCI JOURNAL
The paper deals with the study based on the comparative analysis of radio propagation models for mobile
cellular wireless communication of global system for mobile at frequencies 0.9 GHz and 1.8 GHz,
respectively. The path loss propagation models are vital tool for planning the wireless network as well as
designed to predict path loss in a meticulous environment. Various propagation models: Free-space
model, CCIR (ITU-R) model, Hata model, Ericson model, and Stanford University Interim (SUI) model
have been studied and examined through analytically from the base station (BS) to mobile station (MS)
and vice versa followed by respective simulation performance evaluation by using Matlab simulator. The
observed data is collected at the operating frequency of 0.9 GHz from various environments (high density
region and low density region) using the spectrum analyzer and path loss comparison is shown for
different model.
Path Loss Characterization of 3G Wireless Signal for Urban and Suburban Envir...Onyebuchi nosiri
Abstract - The characteristic effects of propagation environment on wireless communication signals are significant on the transmitted and received signal quality. The study focused on investigative analysis of the effects of propagation environment on the wireless communication signals within some geographical domains in Port Harcourt, River State. Field measurements were carried out in some selected areas namely GRA phase II and Aggrey Road categorized as urban and Sub urban areas respectively using Sony Ericsson (W995) Test Phone and GPS receiver (BU353). The analyses were based on linear regression (mean square error) approach. The computed path loss exponents and standard deviation based on the empirical analyses conducted for urban and suburban environments are 3.57dB, 2.98dB and 19.6, 13.2, respectively. The results obtained were used to compare the performance of the various existing path loss prediction models such as Okumura-Hata, Cost 231 and ECC-33. Okumura-Hata model showed better performance in urban environment while Cost 231 performed better in rural environment. They study therefore recommends the deployment of Okumura-Hata model in urban, while Cost 231for suburban study areas.
Channel Estimation in MIMO OFDM Systems with Tapped Delay Line ModelIJCNCJournal
The continuous increase in the user demands fornew-generation communication systems, is making the wireless channel more complex and challenging for estimation, developing a simulation model for the channel,and evaluating the performance of different MIMO systems. In this work, a simulation model for multipath fading channels in wireless communication is performed. The model includes a selection of typical Tapped-Delay-Line channel models that can be implemented to reproduce the effects of representative channel distortion and interference. Based on the simulation results, the proposed method exhibits accurate channel estimation performance for frequency-selective fading channels. The proposed work employed LS, MMSE, and ML methods for channel estimation, using 16 and 32 pilots and fixed pilot locations in each frame. Results are obtained for 4x4, 8x8, 16x16, 16x8, and 16x4 MIMO systems and tapped delay line systems.
Channel Estimation in MIMO OFDM Systems with Tapped Delay Line ModelIJCNCJournal
The continuous increase in the user demands fornew-generation communication systems, is making the wireless channel more complex and challenging for estimation, developing a simulation model for the channel,and evaluating the performance of different MIMO systems. In this work, a simulation model for multipath fading channels in wireless communication is performed. The model includes a selection of typical Tapped-Delay-Line channel models that can be implemented to reproduce the effects of representative channel distortion and interference. Based on the simulation results, the proposed method exhibits accurate channel estimation performance for frequency-selective fading channels. The proposed work employed LS, MMSE, and ML methods for channel estimation, using 16 and 32 pilots and fixed pilot locations in each frame. Results are obtained for 4x4, 8x8, 16x16, 16x8, and 16x4 MIMO systems and tapped delay line systems.
Securing your Kubernetes cluster_ a step-by-step guide to success !KatiaHIMEUR1
Today, after several years of existence, an extremely active community and an ultra-dynamic ecosystem, Kubernetes has established itself as the de facto standard in container orchestration. Thanks to a wide range of managed services, it has never been so easy to set up a ready-to-use Kubernetes cluster.
However, this ease of use means that the subject of security in Kubernetes is often left for later, or even neglected. This exposes companies to significant risks.
In this talk, I'll show you step-by-step how to secure your Kubernetes cluster for greater peace of mind and reliability.
UiPath Test Automation using UiPath Test Suite series, part 4DianaGray10
Welcome to UiPath Test Automation using UiPath Test Suite series part 4. In this session, we will cover Test Manager overview along with SAP heatmap.
The UiPath Test Manager overview with SAP heatmap webinar offers a concise yet comprehensive exploration of the role of a Test Manager within SAP environments, coupled with the utilization of heatmaps for effective testing strategies.
Participants will gain insights into the responsibilities, challenges, and best practices associated with test management in SAP projects. Additionally, the webinar delves into the significance of heatmaps as a visual aid for identifying testing priorities, areas of risk, and resource allocation within SAP landscapes. Through this session, attendees can expect to enhance their understanding of test management principles while learning practical approaches to optimize testing processes in SAP environments using heatmap visualization techniques
What will you get from this session?
1. Insights into SAP testing best practices
2. Heatmap utilization for testing
3. Optimization of testing processes
4. Demo
Topics covered:
Execution from the test manager
Orchestrator execution result
Defect reporting
SAP heatmap example with demo
Speaker:
Deepak Rai, Automation Practice Lead, Boundaryless Group and UiPath MVP
State of ICS and IoT Cyber Threat Landscape Report 2024 previewPrayukth K V
The IoT and OT threat landscape report has been prepared by the Threat Research Team at Sectrio using data from Sectrio, cyber threat intelligence farming facilities spread across over 85 cities around the world. In addition, Sectrio also runs AI-based advanced threat and payload engagement facilities that serve as sinks to attract and engage sophisticated threat actors, and newer malware including new variants and latent threats that are at an earlier stage of development.
The latest edition of the OT/ICS and IoT security Threat Landscape Report 2024 also covers:
State of global ICS asset and network exposure
Sectoral targets and attacks as well as the cost of ransom
Global APT activity, AI usage, actor and tactic profiles, and implications
Rise in volumes of AI-powered cyberattacks
Major cyber events in 2024
Malware and malicious payload trends
Cyberattack types and targets
Vulnerability exploit attempts on CVEs
Attacks on counties – USA
Expansion of bot farms – how, where, and why
In-depth analysis of the cyber threat landscape across North America, South America, Europe, APAC, and the Middle East
Why are attacks on smart factories rising?
Cyber risk predictions
Axis of attacks – Europe
Systemic attacks in the Middle East
Download the full report from here:
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B0340818
1. IOSR Journal of Applied Physics (IOSR-JAP)
e-ISSN: 2278-4861. Volume 3, Issue 4 (Mar. - Apr. 2013), PP 08-18
www.iosrjournals.org
www.iosrjournals.org 8 | Page
Urban Area Path loss Propagation Prediction and Optimisation
Using Hata Model at 800MHz
Isabona Joseph1
, Konyeha. C.C2
1&2
Department of Basic Sciences, Benson Idahosa University, PMB.1100, Benin City, Nigeria
Abstract: This paper describes how Okumura Hata’s model is chosen and optimized for urban outdoor
coverage in the Code Division Multiple Access (CDMA) system operating in 800MHz UHF frequency band,
South-south Nigeria. This optimized path loss model is based on the empirical measurements collected in the
CDMA network focusing on the city centre of Benin, Edo state. It is developed by comparing the calculated
path loss from collected measurements with the well-known path loss models within applicable frequency range
of CDMA system, such as Hata, SUI, Lee, and Egli’s Model. The Hata model was chosen as a reference for this
optimized path loss model development based on the closest path loss exponent and smallest mean error as
compared to the measured path loss. This optimized Hata model is implemented in the path loss calculation
during the validation process. Thus, this optimized model is successfully improved and would be more reliable
to be applied in the Nigeria CDMA system for urban path loss calculation in the 800MHz frequency band.
Key Words: propagation loss prediction, optimisation, Hata model, urban area
I. Introduction
In wireless communications, the information that is transmitted from one end to another propagates in
the form of electromagnetic (EM) wave. All transmitted information incurs path loss as electromagnetic waves
propagate from source to destination (due to e.g., reflection, diffraction, and scattering). It has been expressed in
[1] that electromagnetic effects (such as power attenuation, deep fading and so on) is the major cause of dropped
calls in cellular networks. Hence accurate estimation of propagation path loss is a key factor for the good design
of mobile systems. Propagation path loss models are mathematical tools used by engineers and scientists to plan
and optimize wireless network systems. The main goal in the planning phase of the wireless network is to
predict the loss of signal strength or coverage in a particular location. Manoj opined in [2], that the quality of
coverage of any wireless network design depends on the accuracy of the propagation model. In order words, the
coverage reliability of a wireless network design depends on the accuracy of the propagation model. In the
optimization phase, the objective is to make sure the network operates as close as possible to the original design
by making sure handoff points are close to prediction; coverage is within design guidelines such as in-door, in-
car, and on-street RSS; and co-channel interference is low at neighboring sites. Also, in the optimization phase
measured data collected from the live network may be used to tune the propagation models utilized in the design
phase.
Specifically, it has been reported in many academic literature (e.g. [3]) that the propagation models
applied for macrocell mobile systems have built-in-error (generally of the order of 7-10dB standard deviation- a
factor of ten in signal power) accounted for during the network design through a margin added to the overall
signal strength calculations to take account of the natural signal fading phenomenon. Any reduction that can be
achieved in this error will increase the quality of service, reduce undesirable power losses, increase coverage
area, and determine best arrangements of base stations. Put in order words, any reduction of the error will have a
direct and significant impact on the size and performance of the network and hence in both the economics and
customer satisfaction of the service. In order to overcome this problem, the parameters of certain empirical
models must be adjusted with reference to the targeted environment in order to achieve minimal error between
predicted and measured signal strength.
Code division multiple access is a channel access method that allows simultaneous transmission of
information from several sources over a single communication channel, with different distinguishing code
patterns [4]. CDMA employs both the spread-spectrum technology and a special coding scheme to allow
multiple users to be multiplexed over the same physical channel. In the CDMA system, the duplex channel is
made of two 1.25MHz-wide bands of spectrum. The carrier frequency of the studied CDMA system network
operator in Benin, South-South Nigeria is called operator B in this paper because of legal reasons and it
transmits at 800MHz band.
The path loss model for the CDMA system is different in that several propagation factors such as the
soft handoff gain, Pilot Number (PN) pollution, Pilot energy over total energy received (Ec/Io), etc are taken
into consideration. The soft handoff factor can provide multi-path diversity on the forward link at sites’ edges. It
2. Urban Area Pathloss Propagation Prediction and Optimisation Using Hata Model at 800MHz
www.iosrjournals.org 9 | Page
helps to improve channels’ anti-fading capability and reduces Mobile Station’s transmit power. As such, it
decreases the interference caused by the system mobile station.
On the other hand, it supplies some significant gains on the reverse coverage. However, the path loss
calculated for the CDMA network can be derived from the forward link and the transmission path from a base
transceiver station to the mobile station. All measurements are collected within a radius of 2km away from the
base station, with seamless coverage and no blind spots. Thus, the minimum allowable path loss is not
considered as the tested base station. Nearing the adjacent base stations, noted that handover occurred as signal
is weak.
In this study we describe how Hata model is chosen and optimized for urban outdoor coverage in the
Code Division Multiple Access (CDMA) system in Benin City, South-south Nigeria.
II. Methodology
Several existing path loss models such as Hata’s Model [5], Stanford University Interrim (SUI) model
[6], Lee’s Model [7] and Egli’s Model [8] are chosen for comparison with measurement data. The best existing
path loss model with the closest propagation exponent [8], to the measured path loss data will be chosen as a
reference for the development of the optimized path loss model. The optimized path loss model will be tested
during the validation process by comparing the calculated path loss to the measured path loss in Benin City
CDMA Network.
Propagation Models
Four existing path loss models are chosen as reference in the development of the optimized path loss
model. These existing path loss models are Hata’s Model, Lee’s model, SUI model and Egli Model. These path
loss models were developed empirically in the system with similar antenna heights and frequency ranges which
are applicable to the CDMA network in Benin City.
HATA Path loss Model
The Hata model is based on Okumura's measurements in Tokyo, which were fitted into a mathematical
model by Hata. The original Okumura-Hata formula is given in Equation (1) [9]:
L = 69.55+26.16log10 (f)-13.82log10 (hBS)-a (hMS) + [44.9-6.55log10 (hBS) log10 (d) (1)
where a is defined as:
a(hMS) = [1.1 log10(f) – 0.7] hMS - [1.56 log10(f) – 0.8] (2)
a(hMS) = 3.2 [log10(11.75hMS)]2
– 4.97 (3)
Equation (2) is used for small and medium cities and Equation (3) for large cities.
Other definitions used in Equation (1) are:
L= Path loss (dB)
F= Frequency (150 – 1500) MHz
hBS = Base station effective antenna height (20 – 200) m)
hMS= Mobile station antenna height (1 – 10) m)
d =Distance between base and mobile station (1 – 20) km)
The original Okumura-Hata has some limitations. The most restrictive is that Okumura's measurements
were made at 1920 MHz, and Hata's formulas cover only frequencies range from 150 to 1500 MHz. Also
antennas have been over average rooftop level.
The original formula has been modified by COST-231 -project, which resulted in extending Okumura-
Hata formula to cover frequencies from 1500 to 2000 GHz. This makes it possible to use the formula in
simulations for 3G-networks for a reasonable accuracy. Constants A and B are redefined, and distance
dependence parameter C is recommended to be defined by measurements, but value 44.9 is still often used. The
COST-231-Hata –formula is given in Equation 2.69. Constants A and B are chosen from the Table 1. Also an
additional environment dependent parameter, area type correction factor, Cm, is given. It is above 0 dB in urban
areas, but in rural areas it can be even below -15 dB [10]:
L = A+B log10(f)-3.82log10(hBS)-a (hMS)+[C-6:55 log10(hBS)] log10(d)+Cm (4)
New definitions in the formula are:
A Constant, see Table 1
B Constant, see Table 1
C User defined value for distance dependence (slope factor)
Cm Area correction factor.
3. Urban Area Pathloss Propagation Prediction and Optimisation Using Hata Model at 800MHz
www.iosrjournals.org 10 | Page
TABLE 1: CONSTANTS A AND B FOR HATA
150-1000MHz 1500-2000MHz
A 69.55 46.3
B 26.16 39.9
Stanford University Interim (SUI) Model
The SUI model was developed under the Institute of Electrical and Electronics Engineers (IEEE)
802.16 working group for prediction of path loss in urban, suburban and rural environments [5].The
applicability of this model in the 800 MHz and 1900MHz band has not been validated. However, due to the
availability of correction factors for the operating frequency, this model is selected. The SUI models are divided
into three types of terrains, namely, A, B, and C. Type A is associated with maximum path loss and is
appropriate for hilly terrain with moderate to heavy foliage densities. Type C is associated with minimum path
loss and applies to flat terrain with light trees densities. Type B is associated characterized with either mostly
flat terrains with moderate to heavy three density or hilly terrains with light tree densities. The basic path loss
equation with correction factors is presented in [5]:
dodforSXX
do
d
nAdBL bf
10log10 (5)
where d is the distance between the Access Point (AP) and mobile station in meters, mdo 100 and S is a
log normally distributed factor that is used to account for the shadow fading owning to tree and other cluster and
has a valued between 8.2 dB and 10.6dB [11]. The other parameters are defined as
A
d
A o4
log20 10 (6)
b
b h
Cbhan (7)
where the parameter bh is the base station height above the ground in metres and should be between 10m and
80m. The constants used a, b, and c is given in Table 2. The parameter n in (1) is equal to the path loss
exponent. For a given terrain type the path loss exponent is determined by bh
Table 2: The parameters of SUI model in different environment
Model parameter Terrain
A
Terrain
B
Terrain
C
a
b (m-1
)
c (m)
4.6
0.0075
12.6
4.0
0.0065
17.1
3.6
0.005
20
The correction factors for the operating frequency and the mobile station antenna height for the model are [12]:
2000
log0.6 10
fX f (8)
and
BandATerrainfor
hr
X h
2000
log8.10 10 (9)
2000
log0.20 10
hr
for Terrain type C (10)
where, f is the frequency in MHz and hr is the mobile antenna height above the ground in metres. The SUI
model is used to predict the path loss in all three environments, namely rural, suburban and urban.
The LEE Model
W. C. Y. Lee proposed this model in 1982 [6]. In a very short time it became widely popular among
researchers and system engineers (especially among those employed by U.S. companies) mainly because the
parameters of the model can be easily adjusted to the local environment by additional field calibration
4. Urban Area Pathloss Propagation Prediction and Optimisation Using Hata Model at 800MHz
www.iosrjournals.org 11 | Page
measurements (drive tests). By doing so, greater accuracy of the model can be achieved. The LEE path loss
model is given by [12]:
MHz
f
n
km
r
ogLoLp
900
log10
6.1
1010
(11)
Where 2
1
54321
48.30
m
mhightantennanewBS
Table 3: Parameters for Lee’s path loss model
Environment
L
Free space 80 2.0
Open Area 89 4.35
North American Suburban 101.7 3.85
North American Urban 110 3.68
North American Urban 104 4.31
Japanese Urban 124 3.05
:2320
4
2/
10
3
5
4
2
3
2
valuesfollowingthetaketodrecommendedataempiricalonbasedalsoareinandinnofvaluesthe
MSthetafactorcorrectiongainantennadifferent
dipoletorespectwithgainantennaBSnew
W
powerrtransmittenew
m
mhightantennaMSnew
c
areaurbaninandMHzffor
areaopensuburbaninandMHzfforn
c
c
4500.3
/4500.2
mhightantennaforMS
mhightantennaMSfor
30.3
100.2
The Clutter Factor Model
The Egli Model is a terrain model for radio frequency propagation. This model consists of the plane
earth loss plus an extra loss component called the clutter factor. An example of clutter factor model is the
method due to Egli, which is based upon a large number of measurements
The formulas for the Egli's propagation loss prediction model are as below [12]:
For hms ≤ 10,
PL (dB) = 20 log10 fc+40 log10 R+20 log10 hbs+76:3-10 log10 hms (12)
For hms ≥10,
PL (dB) = 20 log10 fc+40 log10 R+20 log10 hbs+85:9-10 log10 hms (13)
III. Measurement Configuration
A schematic diagram of the Field measurement set-up is shown in Figure 1. The testing tool used in the
measurement was NOKIA 1265 CDMA test phone handset in the Net Monitor mode, in conjunction with a
digital Global positioning System (MAP76CSX GPS) receiver antenna to determine distance (d) from the Base
Station (BS). The software comprises a scale, which is calibrated in (dBm) [13]
5. Urban Area Pathloss Propagation Prediction and Optimisation Using Hata Model at 800MHz
www.iosrjournals.org 12 | Page
In all the study locations, BS transmitting antenna were dual band with inbuilt features, which enables them
to radiate at 800MHz for operator A with antenna height of 40m above the sea level in all study access sites.
The antennas were sectored 1200
. An approximate height of 1.5m was used as mobile receiver height.
Figure1: A set-up Field-test measurement
Measurement Environment
Past study reveals that determining the propagation of a city requires taking measurement at various high
and low environment or taking exhaustive measurement round the city to cover all the possible terrain conditions
[14]-[15]. In this study, the focus is on the first approach. A total of four base station sites were investigated and
the choice of the number of sites in each environment was based on the availability of the network provider.
Benin City was chosen to represent a typical urban region which consists of blocks densely built-up buildings of
different heights and streets widths with small bushes and few trees. It lies within latitude 6.31760N and longitude
5.61450E [16]. It is situated 200 miles by road, east of Lagos with a population of about 1,147,188.
Measurement Procedure
With the aid of testing tool (i.e. NOKIA mobile handset) running on the software mode, calls were
initiated at each test point until it is established and the signal strength information sent over the air interface
between the base and the mobile station were read. For every site, received signal strength was measured at a
reference distance of 100m from the base station and at subsequent interval of 100m up to 2000m. All
measurements were taken in the mobile active mode and in three sectors of each base station. This was to ensure
that the mobile phone was in constant touch with the base station. Also, measurements were taken on a uniform
grid of outdoor static positions. This methodology is slightly different from the usual convectional drive-test
procedure which may not cover certain inaccessible areas. At the same time, it presents some advantages
because continuous measurement at the same point is captured, and this reduces systematic errors by properly
windowing and averaging data.
Given in table 1 are the definition of the basic parameters/ specification of the CDMA networks of the two
operators in the chosen area of study.
IV. Results and Discussion
The path loss estimated by the SUI, COST-231 Hata, and Egli models are calculated, and plotted
against distance on the same graph as that of the measured path loss (figure 2-5).
6. Urban Area Pathloss Propagation Prediction and Optimisation Using Hata Model at 800MHz
www.iosrjournals.org 13 | Page
Figure 2: Comparative path loss model in BS 1
Figure 3: Comparative path loss model in BS 2
Figure 4: Comparative path loss model in BS 3
60
80
100
120
140
160
180
0 0.5 1 1.5 2 2.5
Pathloss(dB)
Distance(km)
Measurementpathloss
COST-231 Hata
SUI
Lee
Egli
60
80
100
120
140
160
180
0 0.5 1 1.5 2 2.5
Pathloss(dB)
Distance(km)
MeaurementPathloss
COST-231 Hata
SUI
Lee
60
80
100
120
140
160
180
0 0.5 1 1.5 2 2.5
Pathloss(dB)
Distance(km)
MeasuremntPathloss
COST-231 Hata
SUI
Lee
Egli
7. Urban Area Pathloss Propagation Prediction and Optimisation Using Hata Model at 800MHz
www.iosrjournals.org 14 | Page
Figure 5: Comparative path loss model in BS 4
Path loss Model Optimisation
Path loss model optimisation is a process in which a theoretical propagation model is adjusted with the
help of measured values obtained from test field data. The aim is to get the predicted field strength as close as
possible to the measured field strength. Propagation path loss models optimized for different wireless
technologies and environments are abundant in literature (e.g., [17]-[19]. Figure 5 below illustrates how
measured path loss models have been optimised with Hata’s model in this thesis.
Figure 6: The flow chart of Path loss Optimisation process
Filtering Process and Best Model Selection
In order to obtain a specific path loss model for the operator in the four study sites, we took the
average path loss PL = E [PL], of each of the operators, where E[·] denotes averaging operators. This approach
is referred to as filtering the variations [19]. Table 3 below shows the results of the average path loss for each
site.
Table 3. The path loss exponents found from the slopes of these graphs of measured data
BS Site Path loss exponent Intercept
BS 1 3.18 123.20
BS 2 2.52 122.40
BS 3 2.88 128.10
BS 4 2.82 120.40
Average 2.85 123.53
The path loss exponents found from the slopes of these graphs in figure 2-5 are summarized in table 4. From the
tables, the following observations have been made. Hata’s model gave a closest prediction to the measurement
with a path loss exponent of 3.40. Based on closest agreement, the Hata model is selected as the best model for
optimisation
60
80
100
120
140
160
180
0 0.5 1 1.5 2 2.5
Pathloss(dB)
Distance(km)
Measurementpathloss
COST-231 Hata
SUI
Lee
Egli
8. Urban Area Pathloss Propagation Prediction and Optimisation Using Hata Model at 800MHz
www.iosrjournals.org 15 | Page
Table 4: The path loss exponents and intercepts found from the slopes of these graphs
BS Site 1 2 3 4
n measured 3.12 2.52 2.88 2.82
n COST 3.41 3.41 3.41 3.44
n SUI 3.82 3.83 3.82 3.90
n Lee 3.68 3.68 3.68 3.68
n Egi 4.00 4.00 4.00 4.00
Hata Model optimisation and Validation
In order to optimise and validate the effectiveness of the proposed model, the Mean error (ME), root
mean square error (RMSE) and standard deviation (SD) were calculated between the results of the Hata model
and the measured path loss data of each area. These errors and the standard deviation are defined by the
expression in (14), (15) and (16), respectively.
ME =
∑ 𝑃𝑚−𝑃𝑟 2
𝑁
(14)
RMSE =
∑ 𝑃𝑚−𝑃𝑟 2
𝑁
(15)
SD =
∑ 𝑃𝑚−ў 2
𝑁−1
(16)
where Pm = measured Path loss (dB)
Pr = Predicted Hata Path loss (dB)
N = Number of measured data points
The results of the error computation is given in table 1 below
The parameters of the Hata path loss model were adjusted using least square algorithm to fit to measured data
using the following process. First, the residual between measured path loss, Pm, and the predicted value, Pr, by
the Model is calculated for each location point which is a distance d from the base station by:
Pm - Pr = Pm -[ 43.6+33.9 log fc –13.82 log hr– a(hr)+ (44.9-loght )log d] (17)
where Pm and Pr are in dB and d is in km.
Second, the RMSE function computation of this residual is calculated based on the least squared algorithm
which is used to determine the values of γ that minimizes the residual RMSE.
Thirdly, similar to the work by [18] and [19], the RMSE is then subtracted from the equation (13) of Hata model
to obtain optimised path loss models for all BS sites in the location of study as given in equation (18).
bP hfoptL 1010 log82.13log9.3377.34)( + A d10log – B + C (18)
where
A bh10log55.69.44 (19)
,97.475.11log20.3
2
10 hrB
(20)
C = 0 dB; medium-sized cities
C = 3 dB metropolitan areas
10/log55.69.44 10 bCOST hn (21)
Performance analysis of Optimised Path loss model
Here, the optimized path loss model for each operator was applied for path loss calculation for other
base stations in all the study location, to verify the accuracy and the suitability of this optimized path loss
models. The result shows that all the base stations fit into the optimized model with lower ME, RMSE and
standard deviation (see table 5 below). From these results as depicted in figure 7-10, it is shown that the
optimized model does show a good agreement for the entire studied BS sites compared with Hata model. Thus
the optimized model is successfully developed with proper optimized procedure.
9. Urban Area Pathloss Propagation Prediction and Optimisation Using Hata Model at 800MHz
www.iosrjournals.org 16 | Page
Figure 7: Optimised Hata path loss model with measurement data in BS 1
Figure 8: Optimised Hata path loss model with measurement data in BS 2
Figure 9: Optimised Hata path loss model with measurement data in BS 3
60
70
80
90
100
110
120
130
140
150
160
0 0.5 1 1.5 2 2.5
Pathloss(dB)
Distance(km)
Measurementpathloss
Optimisedpathloss Model
COST-231 Model
60
70
80
90
100
110
120
130
140
150
160
0 0.5 1 1.5 2 2.5
Pathloss(dB)
Distance(km)
MeaurementPathloss
Optimisedpathloss Model
COST-231 Model
60
70
80
90
100
110
120
130
140
150
160
0 0.5 1 1.5 2 2.5
Pathloss(dB)
Distance(km)
MeasuremntPathloss
Optimisedpathloss Model
COST-231 Model
10. Urban Area Pathloss Propagation Prediction and Optimisation Using Hata Model at 800MHz
www.iosrjournals.org 17 | Page
Figure 10: Optimised Hata path loss model with measurement data in BS 4
The results of the error computation is given in table 5 below
Table 5: Proposed model performance before and after optimisation
BS site Before optimisation After optimisation
ME RMSE SD ME RMSE SD
1 12.57 12.88 3.54 0.14 1.87 2.13
2 15.93 16.05 4.08 0.14 2.03 2.02
3 16.48 16.61 4.22 0.02 1.79 1.79
4 15.77 15.89 3.74 0.01 1.81 1.02
Average 15.19 15.36 3.89 0.08 1.88 1.74
V. Conclusion
In this paper, the measured path losses in four cells are compared with theoretical path loss models:
Hata, SUI, Lee and Egli. The measured path loss, when compared with theoretical values from the theoretical
models, showed the closest agreement with the path loss predicted by the Hata model in terms of path loss
exponent prediction and standard deviation error analysis. Based on this, an optimised Hata model for the
prediction of path loss experienced by CDMA2000 signals in the 800MHz band in urban environment of South-
south Nigeria is developed. The optimised model showed high accuracy and is able to predict path loss with
smaller standard deviation errors as compared to the Hata model.
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