Channel assignment strategies
•
1 like•145 views
This document discusses channel assignment strategies in cellular networks. It describes the goals of channel assignment as achieving high spectrum utilization, maintaining service quality, using simple algorithms, and requiring minimal database lookups. It then outlines some common channel assignment processes and strategies like fixed channel assignment, dynamic channel assignment, and quasi-static autonomous frequency assignment. Specific strategies discussed include allocating predetermined channels to each cell, dynamically allocating channels from a central database, and reserving some channels for handoff calls.
Report
Share
Report
Share
Download to read offline
Recommended
Diversity techniques presentation material
This document discusses various diversity techniques used in wireless communications to combat fading. It describes types of diversity including time, frequency, multiuser, and space diversity. It also outlines combining techniques such as selection combining, maximal ratio combining and equal gain combining that are used to improve the signal by combining signals from multiple diversity branches. The document concludes by discussing multiple input multiple output (MIMO) systems and orthogonal frequency division multiple access (OFDMA) schemes that exploit diversity and multiuser diversity.
Small scale fading
Channel issues
Accuracy of Models
Large-scale: Path loss
Medium-scale: Shadowing
Small-scale: Multipath fading
4.5 equalizers and its types
1. Equalizers are used to reduce inter-symbol interference in wireless communication and help reduce bit errors at the receiver.
2. There are two main types of equalizers - linear equalizers and non-linear equalizers. Linear equalizers include zero forcing and MMSE equalizers, while non-linear equalizers include decision feedback equalizers.
3. Adaptive equalizers automatically adapt to changing channel properties over time using algorithms like LMS and RLS to update equalizer coefficients.
Channel assignment strategies
The document discusses different channel assignment strategies for wireless networks, including fixed channel assignment where each cell is predetermined channels and dynamic channel assignment where channels are allocated on request based on factors like channel occupancy. It also describes a partially overlapping channel (FPOC) assignment strategy that aims to increase capacity while minimizing interference through intelligent channel allocation between neighboring nodes.
Ec 2401 wireless communication unit 4
This document provides an overview of signal processing techniques used in wireless systems, including diversity and equalization. It discusses various diversity techniques like spatial, temporal, frequency, angular, and polarization diversity as well as macro and micro diversity. It also explains different types of combining diversity including selection, maximal ratio combining, and equal gain combining. The document concludes with sections on linear equalizers such as zero forcing and MMSE, as well as nonlinear equalizers using algorithms like LMS and RLS.
Speech encoding techniques
Speech coding techniques are used to represent human speech in a digital form for applications like mobile communication and voice over IP. The main components of a speech coding system are speech encoding and decoding. Various coding techniques are used including waveform coding techniques like PCM and ADPCM, and source coding techniques like linear predictive coding (LPC) and vocoding. The aim is to enhance speech quality at a particular bitrate or minimize the bitrate at a given quality level, while considering factors like computational complexity, coding delay, and robustness to different speakers.
SPACE DIVISION MULTIPLE ACCESS (SDMA) SATELLITE COMMUNICATION
SPACE DIVISION MULTIPLE ACCESS (SDMA)
Definition : The communication channel encountered by this array of antennas.
advanced antenna technology.
Smart Antenna
Uplink Transmission
Downlink Transmission
Block Diagram
Features
Beam Frequency Reuse
Advantages
Disadvantages
IS-95 Cdma
IS-95 CDMA is an air interface standard that uses code division multiple access (CDMA). It employs various techniques to improve system capacity and performance, including bandwidth recycling, power control, soft handoffs, diversity combining, and variable rate vocoding. Key aspects of IS-95 include the use of quadrature phase shift keying modulation at a 1.2288 Mcps chip rate, forward error correction coding, and multiple logical channels (pilot, sync, paging, traffic) defined using orthogonal Walsh codes.
Recommended
Diversity techniques presentation material
This document discusses various diversity techniques used in wireless communications to combat fading. It describes types of diversity including time, frequency, multiuser, and space diversity. It also outlines combining techniques such as selection combining, maximal ratio combining and equal gain combining that are used to improve the signal by combining signals from multiple diversity branches. The document concludes by discussing multiple input multiple output (MIMO) systems and orthogonal frequency division multiple access (OFDMA) schemes that exploit diversity and multiuser diversity.
Small scale fading
Channel issues
Accuracy of Models
Large-scale: Path loss
Medium-scale: Shadowing
Small-scale: Multipath fading
4.5 equalizers and its types
1. Equalizers are used to reduce inter-symbol interference in wireless communication and help reduce bit errors at the receiver.
2. There are two main types of equalizers - linear equalizers and non-linear equalizers. Linear equalizers include zero forcing and MMSE equalizers, while non-linear equalizers include decision feedback equalizers.
3. Adaptive equalizers automatically adapt to changing channel properties over time using algorithms like LMS and RLS to update equalizer coefficients.
Channel assignment strategies
The document discusses different channel assignment strategies for wireless networks, including fixed channel assignment where each cell is predetermined channels and dynamic channel assignment where channels are allocated on request based on factors like channel occupancy. It also describes a partially overlapping channel (FPOC) assignment strategy that aims to increase capacity while minimizing interference through intelligent channel allocation between neighboring nodes.
Ec 2401 wireless communication unit 4
This document provides an overview of signal processing techniques used in wireless systems, including diversity and equalization. It discusses various diversity techniques like spatial, temporal, frequency, angular, and polarization diversity as well as macro and micro diversity. It also explains different types of combining diversity including selection, maximal ratio combining, and equal gain combining. The document concludes with sections on linear equalizers such as zero forcing and MMSE, as well as nonlinear equalizers using algorithms like LMS and RLS.
Speech encoding techniques
Speech coding techniques are used to represent human speech in a digital form for applications like mobile communication and voice over IP. The main components of a speech coding system are speech encoding and decoding. Various coding techniques are used including waveform coding techniques like PCM and ADPCM, and source coding techniques like linear predictive coding (LPC) and vocoding. The aim is to enhance speech quality at a particular bitrate or minimize the bitrate at a given quality level, while considering factors like computational complexity, coding delay, and robustness to different speakers.
SPACE DIVISION MULTIPLE ACCESS (SDMA) SATELLITE COMMUNICATION
SPACE DIVISION MULTIPLE ACCESS (SDMA)
Definition : The communication channel encountered by this array of antennas.
advanced antenna technology.
Smart Antenna
Uplink Transmission
Downlink Transmission
Block Diagram
Features
Beam Frequency Reuse
Advantages
Disadvantages
IS-95 Cdma
IS-95 CDMA is an air interface standard that uses code division multiple access (CDMA). It employs various techniques to improve system capacity and performance, including bandwidth recycling, power control, soft handoffs, diversity combining, and variable rate vocoding. Key aspects of IS-95 include the use of quadrature phase shift keying modulation at a 1.2288 Mcps chip rate, forward error correction coding, and multiple logical channels (pilot, sync, paging, traffic) defined using orthogonal Walsh codes.
cellular concepts in wireless communication
The document discusses the concept of frequency reuse in cellular networks. It explains that a limited radio spectrum is used to serve millions of subscribers by dividing the network coverage area into cells and reusing frequencies across spatially separated cells. Each cell is allocated a portion of the total available frequencies, and neighboring cells are assigned different frequencies to minimize interference. The frequency reuse factor is defined as the ratio of the minimum distance between co-channel cells to the cell radius. Larger frequency reuse factors provide better isolation between co-channel cells but reduce network capacity. The document also covers additional topics like different channel assignment strategies, handoff methods, interference calculation and optimization of frequency reuse networks.
Ec 2401 wireless communication unit 3
The document summarizes various digital modulation and demodulation schemes used in wireless communication systems. It describes the structure of a basic wireless communication link and then provides details about modulation formats such as BPSK, DPSK, QPSK, OQPSK, and π/4 QPSK. It explains the key aspects of each scheme such as symbol mapping, transmitter and receiver operations, and their advantages over other schemes in terms of spectral efficiency and robustness to noise and fading channels.
TDMA, FDMA, and CDMA
What are the differences between FDMA, CDMA and TDMA?
How they work?
Adv and DisAdv of them.
Real life applications etc
Diversity Techniques in Wireless Communication
This document discusses diversity techniques for wireless communication, including cooperative diversity. It begins by introducing wireless systems and the impairments they face like fading. It then covers various diversity techniques like space, frequency, and time diversity that provide multiple transmission paths to reduce fading. Cooperative diversity is described as allowing single-antenna devices to achieve MIMO-like benefits by sharing antennas. The document outlines cooperative transmission protocols and challenges at different network layers in implementing cooperation. In conclusion, diversity techniques improve performance by providing multiple signal replicas to overcome fading, while cooperation enables reliability and throughput gains with challenges to address across protocol layers.
Ec 2401 wireless communication unit 2
This document discusses various wireless propagation channels including free space propagation, reflection, scattering, and diffraction. It covers reflection propagation mechanisms such as reflection from dielectrics and conductors. Reflection coefficients and Snell's law are explained. Models for reflection, including the two-ray ground reflection model, are provided. Diffraction models like knife-edge diffraction and multiple knife-edge diffraction using methods like Bollington's method are summarized. Scattering models including Kirchoff's theory and perturbation theory are covered. Common fading models for mobile radio like Rayleigh, Rician, and Doppler shift models are described. Finally, different types of wireless channels including time-selective, frequency-selective, general, and WSSUS channels are classified
Speech coding techniques
This document discusses various techniques for speech coding used in digital communication systems. It covers fundamental concepts like sampling theory, quantization, predictive coding, and linear predictive coding (LPC). It then describes specific speech codecs including PCM, ADPCM, CELP, LD-CELP, ACELP, and LPC vocoders. It discusses characteristics of speech coding like being lossy and metrics like SNR and MOS. Finally, it provides details on widely used standards like G.711, G.729, G.723.1, and GSM.
Equalization
The document discusses equalization techniques used to mitigate inter-symbol interference (ISI) in digital communication systems. Equalization aims to remove ISI and noise effects from the channel. It is located at the receiver and uses techniques like linear equalizers, decision feedback equalization, and maximum likelihood sequence estimation to estimate the channel response and minimize the error between transmitted and received symbols while balancing noise. As the wireless channel changes over time, adaptive equalization is used where the equalizer periodically trains and tracks the changing channel response.
Concept of Diversity & Fading (wireless communication)
This document discusses concepts related to fading and diversity in wireless communication systems. It introduces fading as signal variations caused by multipath interference from multiple signal propagation paths. It describes two types of fading: large-scale fading due to path loss and shadowing, and small-scale fading which includes fast fading due to mobility and slow fading due to shadowing. It also discusses different diversity techniques that can be used to combat fading, including space, polarization, frequency and time diversity.
Spread spectrum modulation
This document provides an overview of spread spectrum technologies including frequency hopping spread spectrum (FHSS) and direct sequence spread spectrum (DSSS). It defines spread spectrum, describes how data is modulated at different rates using DSSS, explains FHSS and DSSS in detail, and lists factors that impact wireless signal performance. Key aspects covered include the FCC regulations for unlicensed use of spread spectrum in the 2.4GHz band, how DSSS spreads and encodes data across multiple frequencies, and how FHSS rapidly hops between frequencies to transmit information.
10. types of small scale fading
This document discusses different types of small scale fading in wireless communication based on time delay spread and Doppler spread. There are four main types of fading: flat fading, frequency selective fading, fast fading, and slow fading. Flat fading occurs when the bandwidth of the signal is less than the bandwidth of the channel and the delay spread is less than the symbol period. Frequency selective fading occurs when the bandwidth of the signal is greater than the bandwidth of the channel and the delay spread is greater than the symbol period. Fast fading occurs when there is a high Doppler spread and the coherence time is less than the symbol period. Slow fading occurs when there is a low Doppler spread and the coherence time is greater than the symbol period.
Outdoor propagatiom model
The document discusses several outdoor propagation models used to predict radio signal strength over long distances. It focuses on the Longley-Rice and Okumura models. The Longley-Rice model predicts transmission loss using terrain profiles and diffraction losses from obstacles. It is available as a computer program that inputs frequency, path length, antenna heights and terrain parameters. The Okumura model uses curves to predict median signal attenuation relative to free space over distances from 1-100 km based on frequency, distance from base station, and terrain factors. It is widely used for cellular predictions in urban environments.
Gsm air interface
This document describes radio transmission techniques and channels in GSM networks. It discusses Frequency Division Multiple Access (FDMA), Time Division Multiple Access (TDMA), and Code Division Multiple Access (CDMA) and defines physical and logical channels. It provides details on different control channels like Broadcast Control Channel (BCCH), Common Control Channel (CCCH), and Dedicated Control Channel (DCCH). It also describes traffic channels and various burst types used in GSM frames.
Propagation Model
This document summarizes key concepts in propagation models for wireless mobile communications. It discusses free space losses, plane earth losses, and models for the wireless channel including macrocells, shadowing, narrowband fast fading, and wideband fast fading. Empirical and physical statistical models are described for modeling propagation in different environments like urban, suburban, and rural areas. Deterministic and statistical models are presented for modeling narrowband fast fading effects.
2. wireless propagation models free space propagation
This document discusses wireless communication propagation mechanisms and propagation models. It explains that when a signal hits an obstacle, it can be reflected, diffracted, or scattered depending on the surface properties. Propagation models are used to predict the average received signal power and design wireless systems by characterizing radio wave propagation based on factors like frequency and distance. Small-scale fading models predict power fluctuations over short ranges, while large-scale models predict average power decreases over large distances between transmitter and receiver.
Spread Spectrum Multiple Access
Spread spectrum communication was first described in 1941 by actress Hedy Lamarr and pianist George Antheil in a patent for a secure radio link to control torpedoes. Spread spectrum works by transmitting signals across a wider bandwidth than the minimum needed using a code known by the transmitter and receiver. It provides benefits like immunity to interference and robust multiple access capability, though it is not bandwidth efficient for single users. Some examples of multiple access techniques that use spread spectrum are frequency hopping and direct sequence spread spectrum.
GSM channels
Physical channels carry information over the air interface between the mobile station and base transceiver station. Logical channels map user data and signaling information onto physical channels. There are two main types of logical channels - traffic channels which carry call data, and control channels which communicate service information. Control channels include broadcast channels which transmit cell-wide information, common channels used for paging and access procedures, and dedicated channels for signaling during calls or when not on a call. Logical channels are mapped onto physical channels to effectively transmit information wirelessly between network components in a GSM system.
Multiple access techniques for wireless communications
Subject: wireless mobile communication.
Topics covered : FDMA, TDMA , Spread Spectrum Multiple Access,Space Division Multiple Access,Capacity of Cellular systems
VSB
Vestigial sideband (VSB) modulation is a technique that is a compromise between double sideband suppressed carrier (DSB-SC) and single sideband (SSB) modulation. In VSB, one sideband is transmitted completely and the other sideband (called the vestigial sideband) is only partially transmitted. This allows for more efficient use of bandwidth than DSB-SC while avoiding some of the information loss that can occur with practical SSB filters. VSB modulation is commonly used for television signal transmission because it provides a good balance between bandwidth usage and demodulation complexity.
Frequency hopping spread spectrum
Frequency hopping spread spectrum (FH-SS) is a type of spread spectrum technique where the available channel bandwidth is divided into a large number of frequency slots arranged continuously. A transmitted signal occupies one or more of the available frequency slots, with the frequencies selected pseudo-randomly based on the output of a pseudo-noise generator. There are two types of FH-SS: slow FH-SS where one or more data bits are transmitted within one hop, and fast FH-SS where one data bit is divided over multiple hops. FH-SS provides advantages like improved interference rejection, code division multiplexing for CDMA, secure communication, and increased capacity and spectral efficiency. It is used in military communication systems, satellite communication,
Source coding
The document discusses information theory and source coding. It defines information and entropy, explaining that the amount of information contained in a message depends on its probability. The entropy of a data source measures the average information content. Huffman coding is presented as a method to assign variable-length codes to symbols to minimize the average code length. Error detection and correction codes are also summarized, including parity checking, cyclic redundancy checks (CRC), linear block codes, and convolutional codes.
2_cellular_network of mobile computing explained
The document discusses cellular network concepts and architecture. It introduces key terminology like base station, mobile switching center, mobile station, voice channels and control channels. It describes how a cellular call is initiated and maintained, including handoffs between cells. It discusses cellular design considerations like frequency reuse, co-channel interference, cell shape and size. Handoff strategies including mobile assisted handoff are covered. The document also provides an overview of the GSM cellular standard.
Lesson 2d channel assignment strategies.pptx
This document discusses different methods for allocating channels in wireless communication systems. It describes three main categories: fixed channel allocation, dynamic channel allocation, and hybrid channel allocation. Fixed allocation assigns channels to each cell permanently. Dynamic allocation selects channels for each call request considering factors like future blocking. Hybrid allocation combines fixed and dynamic approaches, allowing cells to borrow channels from neighbors when needed. The choice of allocation strategy impacts system performance, especially during handoffs between cells.
More Related Content
What's hot
cellular concepts in wireless communication
The document discusses the concept of frequency reuse in cellular networks. It explains that a limited radio spectrum is used to serve millions of subscribers by dividing the network coverage area into cells and reusing frequencies across spatially separated cells. Each cell is allocated a portion of the total available frequencies, and neighboring cells are assigned different frequencies to minimize interference. The frequency reuse factor is defined as the ratio of the minimum distance between co-channel cells to the cell radius. Larger frequency reuse factors provide better isolation between co-channel cells but reduce network capacity. The document also covers additional topics like different channel assignment strategies, handoff methods, interference calculation and optimization of frequency reuse networks.
Ec 2401 wireless communication unit 3
The document summarizes various digital modulation and demodulation schemes used in wireless communication systems. It describes the structure of a basic wireless communication link and then provides details about modulation formats such as BPSK, DPSK, QPSK, OQPSK, and π/4 QPSK. It explains the key aspects of each scheme such as symbol mapping, transmitter and receiver operations, and their advantages over other schemes in terms of spectral efficiency and robustness to noise and fading channels.
TDMA, FDMA, and CDMA
What are the differences between FDMA, CDMA and TDMA?
How they work?
Adv and DisAdv of them.
Real life applications etc
Diversity Techniques in Wireless Communication
This document discusses diversity techniques for wireless communication, including cooperative diversity. It begins by introducing wireless systems and the impairments they face like fading. It then covers various diversity techniques like space, frequency, and time diversity that provide multiple transmission paths to reduce fading. Cooperative diversity is described as allowing single-antenna devices to achieve MIMO-like benefits by sharing antennas. The document outlines cooperative transmission protocols and challenges at different network layers in implementing cooperation. In conclusion, diversity techniques improve performance by providing multiple signal replicas to overcome fading, while cooperation enables reliability and throughput gains with challenges to address across protocol layers.
Ec 2401 wireless communication unit 2
This document discusses various wireless propagation channels including free space propagation, reflection, scattering, and diffraction. It covers reflection propagation mechanisms such as reflection from dielectrics and conductors. Reflection coefficients and Snell's law are explained. Models for reflection, including the two-ray ground reflection model, are provided. Diffraction models like knife-edge diffraction and multiple knife-edge diffraction using methods like Bollington's method are summarized. Scattering models including Kirchoff's theory and perturbation theory are covered. Common fading models for mobile radio like Rayleigh, Rician, and Doppler shift models are described. Finally, different types of wireless channels including time-selective, frequency-selective, general, and WSSUS channels are classified
Speech coding techniques
This document discusses various techniques for speech coding used in digital communication systems. It covers fundamental concepts like sampling theory, quantization, predictive coding, and linear predictive coding (LPC). It then describes specific speech codecs including PCM, ADPCM, CELP, LD-CELP, ACELP, and LPC vocoders. It discusses characteristics of speech coding like being lossy and metrics like SNR and MOS. Finally, it provides details on widely used standards like G.711, G.729, G.723.1, and GSM.
Equalization
The document discusses equalization techniques used to mitigate inter-symbol interference (ISI) in digital communication systems. Equalization aims to remove ISI and noise effects from the channel. It is located at the receiver and uses techniques like linear equalizers, decision feedback equalization, and maximum likelihood sequence estimation to estimate the channel response and minimize the error between transmitted and received symbols while balancing noise. As the wireless channel changes over time, adaptive equalization is used where the equalizer periodically trains and tracks the changing channel response.
Concept of Diversity & Fading (wireless communication)
This document discusses concepts related to fading and diversity in wireless communication systems. It introduces fading as signal variations caused by multipath interference from multiple signal propagation paths. It describes two types of fading: large-scale fading due to path loss and shadowing, and small-scale fading which includes fast fading due to mobility and slow fading due to shadowing. It also discusses different diversity techniques that can be used to combat fading, including space, polarization, frequency and time diversity.
Spread spectrum modulation
This document provides an overview of spread spectrum technologies including frequency hopping spread spectrum (FHSS) and direct sequence spread spectrum (DSSS). It defines spread spectrum, describes how data is modulated at different rates using DSSS, explains FHSS and DSSS in detail, and lists factors that impact wireless signal performance. Key aspects covered include the FCC regulations for unlicensed use of spread spectrum in the 2.4GHz band, how DSSS spreads and encodes data across multiple frequencies, and how FHSS rapidly hops between frequencies to transmit information.
10. types of small scale fading
This document discusses different types of small scale fading in wireless communication based on time delay spread and Doppler spread. There are four main types of fading: flat fading, frequency selective fading, fast fading, and slow fading. Flat fading occurs when the bandwidth of the signal is less than the bandwidth of the channel and the delay spread is less than the symbol period. Frequency selective fading occurs when the bandwidth of the signal is greater than the bandwidth of the channel and the delay spread is greater than the symbol period. Fast fading occurs when there is a high Doppler spread and the coherence time is less than the symbol period. Slow fading occurs when there is a low Doppler spread and the coherence time is greater than the symbol period.
Outdoor propagatiom model
The document discusses several outdoor propagation models used to predict radio signal strength over long distances. It focuses on the Longley-Rice and Okumura models. The Longley-Rice model predicts transmission loss using terrain profiles and diffraction losses from obstacles. It is available as a computer program that inputs frequency, path length, antenna heights and terrain parameters. The Okumura model uses curves to predict median signal attenuation relative to free space over distances from 1-100 km based on frequency, distance from base station, and terrain factors. It is widely used for cellular predictions in urban environments.
Gsm air interface
This document describes radio transmission techniques and channels in GSM networks. It discusses Frequency Division Multiple Access (FDMA), Time Division Multiple Access (TDMA), and Code Division Multiple Access (CDMA) and defines physical and logical channels. It provides details on different control channels like Broadcast Control Channel (BCCH), Common Control Channel (CCCH), and Dedicated Control Channel (DCCH). It also describes traffic channels and various burst types used in GSM frames.
Propagation Model
This document summarizes key concepts in propagation models for wireless mobile communications. It discusses free space losses, plane earth losses, and models for the wireless channel including macrocells, shadowing, narrowband fast fading, and wideband fast fading. Empirical and physical statistical models are described for modeling propagation in different environments like urban, suburban, and rural areas. Deterministic and statistical models are presented for modeling narrowband fast fading effects.
2. wireless propagation models free space propagation
This document discusses wireless communication propagation mechanisms and propagation models. It explains that when a signal hits an obstacle, it can be reflected, diffracted, or scattered depending on the surface properties. Propagation models are used to predict the average received signal power and design wireless systems by characterizing radio wave propagation based on factors like frequency and distance. Small-scale fading models predict power fluctuations over short ranges, while large-scale models predict average power decreases over large distances between transmitter and receiver.
Spread Spectrum Multiple Access
Spread spectrum communication was first described in 1941 by actress Hedy Lamarr and pianist George Antheil in a patent for a secure radio link to control torpedoes. Spread spectrum works by transmitting signals across a wider bandwidth than the minimum needed using a code known by the transmitter and receiver. It provides benefits like immunity to interference and robust multiple access capability, though it is not bandwidth efficient for single users. Some examples of multiple access techniques that use spread spectrum are frequency hopping and direct sequence spread spectrum.
GSM channels
Physical channels carry information over the air interface between the mobile station and base transceiver station. Logical channels map user data and signaling information onto physical channels. There are two main types of logical channels - traffic channels which carry call data, and control channels which communicate service information. Control channels include broadcast channels which transmit cell-wide information, common channels used for paging and access procedures, and dedicated channels for signaling during calls or when not on a call. Logical channels are mapped onto physical channels to effectively transmit information wirelessly between network components in a GSM system.
Multiple access techniques for wireless communications
Subject: wireless mobile communication.
Topics covered : FDMA, TDMA , Spread Spectrum Multiple Access,Space Division Multiple Access,Capacity of Cellular systems
VSB
Vestigial sideband (VSB) modulation is a technique that is a compromise between double sideband suppressed carrier (DSB-SC) and single sideband (SSB) modulation. In VSB, one sideband is transmitted completely and the other sideband (called the vestigial sideband) is only partially transmitted. This allows for more efficient use of bandwidth than DSB-SC while avoiding some of the information loss that can occur with practical SSB filters. VSB modulation is commonly used for television signal transmission because it provides a good balance between bandwidth usage and demodulation complexity.
Frequency hopping spread spectrum
Frequency hopping spread spectrum (FH-SS) is a type of spread spectrum technique where the available channel bandwidth is divided into a large number of frequency slots arranged continuously. A transmitted signal occupies one or more of the available frequency slots, with the frequencies selected pseudo-randomly based on the output of a pseudo-noise generator. There are two types of FH-SS: slow FH-SS where one or more data bits are transmitted within one hop, and fast FH-SS where one data bit is divided over multiple hops. FH-SS provides advantages like improved interference rejection, code division multiplexing for CDMA, secure communication, and increased capacity and spectral efficiency. It is used in military communication systems, satellite communication,
Source coding
The document discusses information theory and source coding. It defines information and entropy, explaining that the amount of information contained in a message depends on its probability. The entropy of a data source measures the average information content. Huffman coding is presented as a method to assign variable-length codes to symbols to minimize the average code length. Error detection and correction codes are also summarized, including parity checking, cyclic redundancy checks (CRC), linear block codes, and convolutional codes.
What's hot (20)
Concept of Diversity & Fading (wireless communication)
Concept of Diversity & Fading (wireless communication)
2. wireless propagation models free space propagation
2. wireless propagation models free space propagation
Multiple access techniques for wireless communications
Multiple access techniques for wireless communications
Similar to Channel assignment strategies
2_cellular_network of mobile computing explained
The document discusses cellular network concepts and architecture. It introduces key terminology like base station, mobile switching center, mobile station, voice channels and control channels. It describes how a cellular call is initiated and maintained, including handoffs between cells. It discusses cellular design considerations like frequency reuse, co-channel interference, cell shape and size. Handoff strategies including mobile assisted handoff are covered. The document also provides an overview of the GSM cellular standard.
Lesson 2d channel assignment strategies.pptx
This document discusses different methods for allocating channels in wireless communication systems. It describes three main categories: fixed channel allocation, dynamic channel allocation, and hybrid channel allocation. Fixed allocation assigns channels to each cell permanently. Dynamic allocation selects channels for each call request considering factors like future blocking. Hybrid allocation combines fixed and dynamic approaches, allowing cells to borrow channels from neighbors when needed. The choice of allocation strategy impacts system performance, especially during handoffs between cells.
Fundamental of cellular system
This presentation contains the basic of cellular system.
in which direction the cellular system works and how it changes the network from one bast station to another is simply explained.
how Hand-off occur between two base station is shown via figure to understand well.
the cell system in mobile network and the cell spliting, sectoring, microcell zone concept is also explained well.
Please take a look.
may be it is helpfull for you.
Thank you.
fundamenatals of cellular enginering
The document provides an overview of fundamental concepts in cellular engineering. It discusses the goals of cellular systems to have high capacity and large coverage area through efficient use of limited spectrum. Key concepts explained include frequency reuse, where the same radio channels are reused in different cells to serve more users; channel assignment strategies like fixed and dynamic allocation; and techniques to enhance capacity like cell splitting, sectoring, and microcell zones. The handoff process is also summarized, which allows seamless transfer of calls between base stations as users move between cells.
Lec 7 part one.pptx
1) Frequency management divides available channels into subsets which can be assigned to each cell site either fixedly or dynamically. Channel assignment allocates specific channels to cell sites and mobile units.
2) Channels are numbered and divided into groups, with 666 total channels divided into blocks A and B of 333 channels each. Channels are further divided into voice channels and setup channels.
3) Setup channels are used to setup calls and are assigned one per sector, with 21 sectors requiring 21 setup channels. They are used for both mobile-originating and land-originating calls.
EC3501-WC.pptx
This document discusses cellular network fundamentals including channel assignment strategies, handoff strategies, and practical handoff considerations. It describes fixed and dynamic channel assignment and explains that handoffs are given higher priority than new calls to reduce dropped calls. The document outlines factors that influence handoff decisions and dwell times, and describes different types of handoffs including hard and soft handoffs.
M & WC unit 1.pptx very good condition and success
The document discusses various handoff strategies used in cellular networks. It explains that handoff is required when a mobile moves between base stations to transfer an ongoing call to a new channel and base station. It describes different types of handoff like hard handoff in TDMA networks and soft handoff in CDMA networks. It also discusses factors like minimizing unnecessary handoffs, ensuring successful handoffs, and making handoffs imperceptible to users.
05. Frequency Management and Channel Assignment.pdf
This document discusses frequency management and channel assignment in cellular networks. It covers:
- Frequency management which includes designating setup and voice channels, numbering channels, and grouping voice channels into subsets.
- Channel assignment which allocates specific channels to cell sites on a long-term basis and mobile units on a short-term basis during calls.
- The original 666 channels were divided into blocks A and B, with setup channels in specific ranges and voice channels assigned to each block. Additional spectrum has since been added up to channel 1023.
Freq reuse detail.ppt
This document discusses key concepts in cellular systems including frequency reuse, interference management, and capacity improvement techniques. The main points are:
1. Cells reuse radio frequencies to allow large numbers of users by allocating different frequency groups to neighboring cells. This reduces interference within tolerable limits.
2. Interference is managed through techniques like frequency planning, channel assignment strategies, and power control. The balance of interference and capacity is important.
3. System capacity can be improved through cell splitting, sectoring cells with directional antennas, using different cell sizes, and coverage zone techniques. Managing interference is crucial to improving cellular network capacity.
Lecture 6 t
Cellular networks divide coverage areas into hexagonal cells served by base stations to allow frequency reuse. Adjacent cells use different channels to reduce interference. As demand increases, more base stations are added and transmission power is decreased. Handoff allows calls to be transferred between base stations as users move. Different handoff strategies prioritize maintaining connections during mobility. Dynamic channel assignment allocates channels when needed to improve spectrum utilization and reduce call blocking.
Channel Allocation.pptx
The document discusses different channel allocation strategies for cellular networks. It describes fixed channel allocation, where channels are permanently assigned to cells. Dynamic channel allocation allows channels to be allocated as needed to cells. Hybrid allocation uses a combination of fixed and dynamic. Channel borrowing allows cells to use channels assigned to neighboring cells if available. The key is to allocate channels efficiently while avoiding interference between cells using the same channel.
Cellular communication
This presentation would clear your basic concept on cellular network/communication....although it is recommend to read about various multiplexing techniques as prerequisites....For further knowledge please read more from books. I hope its useful in someway.
WC PPT UNIT-II.ppt
1) Cellular networks divide a region into smaller areas called cells to improve capacity and reuse frequencies. Each cell contains a base station that can communicate with user equipment within its coverage area.
2) Frequency reuse allows the same set of frequencies to be reused in different cells by ensuring sufficient distance between cells using the same frequencies. This increases overall network capacity.
3) Handoff allows calls to be transferred between base stations as users move between cells to maintain call quality. Various handoff strategies aim to minimize call drops during handoffs.
Wireless network planning and operation
Frequencies management,Channel assignments,
Frequency reuse, System capacity and its improvement: Cell spliting and sectoring, Handoffs & its types, prioritizing handoff, Umbrella cell approach, Cell dragging, Roaming, Co channel and adjacent channel interference, Improving coverage- Repeaters for range extension and microcell zone concept, Examples
Wireless traffic theory and handoff
The document discusses various topics related to mobile and wireless communication including:
1) Cell capacity and reuse, defining how capacity increases as the cluster size decreases but interference also increases.
2) Traffic theory, defining concepts like arrival rate, holding time, load, and blocked calls. Formulas for blocking probability and Erlang B & C are provided.
3) Channel assignment strategies including fixed and dynamic assignment and how their impact on performance.
cellular-communications
The document provides an overview of cellular mobile communications including:
1) The historical development from isolated mobile systems to modern cellular networks with handoff capabilities and connections to public networks.
2) The key components of a cellular system including mobile stations, base transceiver stations, base station controllers, and mobile switching centers.
3) How the cellular concept enables frequency reuse through the use of lower power transmissions in smaller coverage areas called cells, allowing the same frequencies to be reused in separated cells.
02-cellular.ppt
Cellular networks divide geographic areas into cells served by base stations to allow for frequency reuse and accommodate high user capacity. Mobile devices connect to the nearest base station and hand off connections when moving between cells. The network locates mobile devices, sets up and transfers calls between cells, and between cellular and traditional telephone networks.
cdma-technology_compress.pdf
CDMA technology uses code division multiple access to allow multiple users to access the network simultaneously using the same frequency band. It uses pseudo-random noise codes with a spread spectrum technique. The document discusses CDMA components like Walsh codes, frequency bands, and channel concepts. It explains the generation of different CDMA channels including pilot, sync, paging, traffic and access channels. It also covers CDMA operations like call processing states, registration types, and handoff procedures.
MOBILE COMPUTING MODULE 1 CALICUT UNIVERSITY
Mobile computing systems allow computing capabilities to be used while moving. They have four key aspects: the mobile user, mobile device, mobile applications, and mobile network. Personal Communication Services (PCS) provide wireless access and personal mobility services through small terminals to enable communication anywhere and anytime. The basic PCS architecture consists of a radio network with mobile stations, base stations, and base station controllers/radio ports connected to a wireline transport network with mobile switching centers. Mobility management ensures network functionality as users move through location registration, tracking, and handoff between base stations.
Improved Cell Coverage in Hilly Areas using Cellular Antennas
This paper proposes an improved configuration of Cellular Antennas for terrains like hills where network coverage is poor and a number of black spots are very high. The proposed solution delivers efficient and much robust antenna structure which provides better network coverage by using 90-degree sector antennas. The radio spectrum of the 90-degree sector antenna is also shown to give the idea of cell coverage in order to build aseamless network in the region.This paper also proposes different channel allocation schemes that can be used with the proposed antenna configuration to deliver better network coverage and low call dropping probability.
This is achieved by analyzing the terrain of the region and also the cellular traffic in the region. In areas where network traffic is almost constant or have low population, strategies like fixed channel allocation can be used effectively and efficiently. While in the areas where traffic is unpredictable or is subject to regional festivals or tourism, channel strategies like dynamic channel allocation are very useful to fulfill the demand of the overall network. The simulations and validations for the proposed methodology are done using MATLAB.
Similar to Channel assignment strategies (20)
M & WC unit 1.pptx very good condition and success
M & WC unit 1.pptx very good condition and success
05. Frequency Management and Channel Assignment.pdf
05. Frequency Management and Channel Assignment.pdf
Improved Cell Coverage in Hilly Areas using Cellular Antennas
Improved Cell Coverage in Hilly Areas using Cellular Antennas
More from Sri Manakula Vinayagar Engineering College
IoT Methodology.pptx
IoT methodology, IoT Level Specification
Functional View Specification
Operational View Specification
Device and Component Integration
Application Development
ACNS UNIT-5.pdf
- The document discusses air traffic control systems and collision avoidance systems. It provides details on primary radar systems, secondary surveillance radar, ATC transponder modes, airborne equipment, automatic dependent surveillance-broadcast, and airborne collision avoidance systems like TCAS. It describes how these systems work to monitor air traffic and help prevent collisions.
2. ACNS UNIT-1.pptx
Various types of Antennas and their working
Isotropic Antenna and SWR measurement
Block Diagram of Transmitter using AM and FM
Block Diagram of Receiver using AM and FM
1. ACNS UNIT-1.pptx
The document provides an introduction to communication systems for aircraft. It discusses key topics like the radio frequency spectrum, the ionosphere, antenna types, transmitter and receiver designs. The radio frequency spectrum is divided into bands based on propagation characteristics. The ionosphere plays an important role in reflecting radio waves to allow long-distance communication. Different types of antennas are described along with their working principles. Block diagrams of transmitters using AM and FM modulation and different receiver designs like TRF and superheterodyne are covered.
7. Multi-operator D2D communication.pptx
Multi-operator D2D communication allows devices subscribed to different cellular operators to directly communicate. This introduces complexity as operators may not want to share network information. The document discusses multi-operator D2D discovery, mode selection, and spectrum allocation. For discovery, devices listen for messages on their home operator's spectrum. Mode selection algorithms for single operators do not directly apply and need to consider inter-operator interference without information sharing. A proposed algorithm relies on interference measurements reported to the home operator.
11. New challenges in the 5G modelling.pptx
The document discusses new challenges in modeling 5G networks, including:
1) The need for more realistic channel, deployment, propagation, traffic and mobility models to accurately reflect real 5G scenarios.
2) Developing new physical layer abstractions to simulate new waveforms like FBMC and UFMC.
3) Modeling massive MIMO systems with tens to hundreds of antennas at both the transmitter and receiver.
4) Developing channel models for higher millimeter wave frequency bands with larger bandwidths.
5) Properly modeling interference between cellular and device-to-device links that reuse physical resources.
8. Simulation methodology.pptx
This document outlines a simulation methodology for 5G technical work to ensure consistent results from computer simulations. The methodology includes procedures for calibrating simulators, guidelines for evaluating simulations, and mechanisms for validating simulations. It aims to align simulation assumptions to allow for direct comparisons between different 5G technology components, based on the authors' experience with previous simulation work in IMT-Advanced and the METIS project. Finally, some relevant test cases and preferred models are introduced.
10. Calibration.pptx
This document outlines an 8-step process for calibrating a link-level 5G simulator based on an LTE link-level simulator. Each step validates a different component: 1) OFDM modulation, 2) channel coding, 3) SIMO configuration, 4) MIMO transmit diversity, 5) MIMO spatial multiplexing, 6) uplink, 7) alignment with 3GPP requirements, and 8) multi-link calibration. System-level calibration then occurs in two phases for LTE and LTE-Advanced technologies.
9. Evaluation methodology.pptx
The document outlines guidelines for evaluating 5G network performance. It defines key performance indicators such as user throughput, application data rate, cell throughput, spectral efficiency, traffic volume, error rates, delay, network energy performance, and cost. It also discusses channel and propagation modeling, recommending simplified ray-based models for large-scale effects and stochastic geometric models for small-scale effects. International Telecommunication Union channel models are suggested for small-scale modeling.
4. Ultra Reliable and Low Latency Communications.pptx
Ultra-reliable low latency communication (URLLC) is a key capability of 5G networks that enables applications with stringent requirements for latency of 1ms or less and high reliability. URLLC can support mission-critical applications in industries like autonomous vehicles, remote surgery, and factory robotics. 5G aims to provide both low latency and high reliability simultaneously through technologies like edge computing and new radio specifications. Later 5G releases continue enhancing URLLC through features such as redundant transmission paths and physical layer optimizations.
1. Massive Machine-Type Communication.pptx
5G technology enables three key services:
1) Enhanced mobile broadband provides high data transmission rates for streaming high-resolution video, augmented reality, and online gaming.
2) Ultra-reliable low latency communications meets exacting requirements for latency and reliability needed for applications like autonomous vehicles.
3) Massive machine-type communications supports connectivity for a very large number of devices that intermittently transmit small amounts of data, enabling growth in IoT.
1. Coordinated Multi-Point Transmission in 5G.pptx
This document discusses coordinated multi-point (CoMP) transmission techniques in 5G networks. It describes CoMP techniques like joint transmission where data is transmitted simultaneously from multiple nodes, and dynamic point selection where data is transmitted from a single node that can change over time. The document also discusses relaying and network coding techniques for 5G like multi-flow wireless backhauling and buffer-aided relaying. It explains how CoMP can improve performance for cell-edge users by reducing interference through coordination between network nodes.
Real time operating systems
Real Time Systems – Issues in Real Time Computing – Structure of a real time system – Process – Task – Threads.
Classification of Tasks – Task Periodicity – Periodic Tasks- Sporadic Tasks – Aperiodic Tasks – Task Scheduling –
Classification of Scheduling Algorithms – Event Driven Scheduling – Rate monotonic scheduling – Earliest deadline first scheduling.
Inter Process Communication:- Shared data problem, Use of Semaphore(s), Priority Inversion Problem and Deadlock Situations -
Reliability and clock synchronization
Introduction to Reliability Evaluation Techniques –
Reliability Models for Hardware Redundancy –
Permanent faults only - Transient faults.
Introduction to clock synchronization –
A Non-Fault-Tolerant Synchronization Algorithm –
Fault-Tolerant Synchronization in Hardware –
Completely connected zero propagation time system –
Sparse interconnection zero propagation time system –
Fault tolerant analysis with Signal Propagation delays.
Low power embedded system design
Sources of Power Dissipation
Dynamic Power Dissipation
Static Power Dissipation
Power Reduction Techniques
Algorithmic Power Minimization
Architectural Power Minimization
Logic and Circuit Level Power Minimization
Control Logic Power Minimization
System Level Power Management.
Performance Analysis of MIMO–OFDM for PCHBF , RELAY Technique with MMSE For T...
Performance Analysis of MIMO–OFDM for PCHBF , RELAY Technique with MMSE For T...Sri Manakula Vinayagar Engineering College
MIMO – OFDM
Adaptive pilot channel estimation
Hybrid Adaptive Relay Technique
Partially Connected Hybrid Beamforming TechniqueTelecommunication systems
Public switched Telephone networks – Switching system principles–PABX switching– ISDN, Cellular mobile communication systems – GSM, GPRS, DECT, UMTS, IMT2000, Limited range Cordless Phones and Facsimile, Wifi and Bluetooth.
Home appliances
Home Appliances: Basic principle and block diagram of microwave oven; washing machine hardware and software, components of air conditioning and refrigeration systems, Proximity Sensors and accelerometer sensors in home appliances.
loudspeakers and microphones
Crystal Loudspeaker Dynamic Loudspeaker, electrostatic loudspeaker, Permanent Magnet Loudspeaker, Woofers and Tweeters Microphone Characteristics, Crystal Microphone, Carbon Microphones, Dynamic Microphones and Wireless Microphones
Television standards and systems
Television Standards and systems: Components of a TV system –interlacing – composite video signal. Colour TV – Luminance and Chrominance signal; Monochrome and Colour Picture Tubes – Colour TV systems–NTSC, PAL, SECAM-Components of a Remote Control and TV camera tubes, HDTV, LED and LCD TVs, DTH TV.
More from Sri Manakula Vinayagar Engineering College (20)
4. Ultra Reliable and Low Latency Communications.pptx
4. Ultra Reliable and Low Latency Communications.pptx
1. Coordinated Multi-Point Transmission in 5G.pptx
1. Coordinated Multi-Point Transmission in 5G.pptx
Performance Analysis of MIMO–OFDM for PCHBF , RELAY Technique with MMSE For T...
Performance Analysis of MIMO–OFDM for PCHBF , RELAY Technique with MMSE For T...
Recently uploaded
বাংলাদেশ অর্থনৈতিক সমীক্ষা (Economic Review) ২০২৪ UJS App.pdf
বাংলাদেশের অর্থনৈতিক সমীক্ষা ২০২৪ [Bangladesh Economic Review 2024 Bangla.pdf] কম্পিউটার , ট্যাব ও স্মার্ট ফোন ভার্সন সহ সম্পূর্ণ বাংলা ই-বুক বা pdf বই " সুচিপত্র ...বুকমার্ক মেনু 🔖 ও হাইপার লিংক মেনু 📝👆 যুক্ত ..
আমাদের সবার জন্য খুব খুব গুরুত্বপূর্ণ একটি বই ..বিসিএস, ব্যাংক, ইউনিভার্সিটি ভর্তি ও যে কোন প্রতিযোগিতা মূলক পরীক্ষার জন্য এর খুব ইম্পরট্যান্ট একটি বিষয় ...তাছাড়া বাংলাদেশের সাম্প্রতিক যে কোন ডাটা বা তথ্য এই বইতে পাবেন ...
তাই একজন নাগরিক হিসাবে এই তথ্য গুলো আপনার জানা প্রয়োজন ...।
বিসিএস ও ব্যাংক এর লিখিত পরীক্ষা ...+এছাড়া মাধ্যমিক ও উচ্চমাধ্যমিকের স্টুডেন্টদের জন্য অনেক কাজে আসবে ...
How to deliver Powerpoint Presentations.pptx
"How to make and deliver dynamic presentations by making it more interactive to captivate your audience attention"
clinical examination of hip joint (1).pdf
described clinical examination all orthopeadic conditions .
Hindi varnamala | hindi alphabet PPT.pdf
हिंदी वर्णमाला पीपीटी, hindi alphabet PPT presentation, hindi varnamala PPT, Hindi Varnamala pdf, हिंदी स्वर, हिंदी व्यंजन, sikhiye hindi varnmala, dr. mulla adam ali, hindi language and literature, hindi alphabet with drawing, hindi alphabet pdf, hindi varnamala for childrens, hindi language, hindi varnamala practice for kids, https://www.drmullaadamali.com
South African Journal of Science: Writing with integrity workshop (2024)
South African Journal of Science: Writing with integrity workshop (2024)Academy of Science of South Africa
A workshop hosted by the South African Journal of Science aimed at postgraduate students and early career researchers with little or no experience in writing and publishing journal articles.BÀI TẬP DẠY THÊM TIẾNG ANH LỚP 7 CẢ NĂM FRIENDS PLUS SÁCH CHÂN TRỜI SÁNG TẠO ...
BÀI TẬP DẠY THÊM TIẾNG ANH LỚP 7 CẢ NĂM FRIENDS PLUS SÁCH CHÂN TRỜI SÁNG TẠO ...Nguyen Thanh Tu Collection
https://app.box.com/s/qhtvq32h4ybf9t49ku85x0n3xl4jhr15BÀI TẬP BỔ TRỢ TIẾNG ANH 8 CẢ NĂM - GLOBAL SUCCESS - NĂM HỌC 2023-2024 (CÓ FI...
BÀI TẬP BỔ TRỢ TIẾNG ANH 8 CẢ NĂM - GLOBAL SUCCESS - NĂM HỌC 2023-2024 (CÓ FI...Nguyen Thanh Tu Collection
https://app.box.com/s/y977uz6bpd3af4qsebv7r9b7s21935vdPCOS corelations and management through Ayurveda.
This presentation includes basic of PCOS their pathology and treatment and also Ayurveda correlation of PCOS and Ayurvedic line of treatment mentioned in classics.
BÀI TẬP BỔ TRỢ TIẾNG ANH LỚP 9 CẢ NĂM - GLOBAL SUCCESS - NĂM HỌC 2024-2025 - ...
BÀI TẬP BỔ TRỢ TIẾNG ANH LỚP 9 CẢ NĂM - GLOBAL SUCCESS - NĂM HỌC 2024-2025 - ...Nguyen Thanh Tu Collection
https://app.box.com/s/tacvl9ekroe9hqupdnjruiypvm9rdaneISO/IEC 27001, ISO/IEC 42001, and GDPR: Best Practices for Implementation and...
Denis is a dynamic and results-driven Chief Information Officer (CIO) with a distinguished career spanning information systems analysis and technical project management. With a proven track record of spearheading the design and delivery of cutting-edge Information Management solutions, he has consistently elevated business operations, streamlined reporting functions, and maximized process efficiency.
Certified as an ISO/IEC 27001: Information Security Management Systems (ISMS) Lead Implementer, Data Protection Officer, and Cyber Risks Analyst, Denis brings a heightened focus on data security, privacy, and cyber resilience to every endeavor.
His expertise extends across a diverse spectrum of reporting, database, and web development applications, underpinned by an exceptional grasp of data storage and virtualization technologies. His proficiency in application testing, database administration, and data cleansing ensures seamless execution of complex projects.
What sets Denis apart is his comprehensive understanding of Business and Systems Analysis technologies, honed through involvement in all phases of the Software Development Lifecycle (SDLC). From meticulous requirements gathering to precise analysis, innovative design, rigorous development, thorough testing, and successful implementation, he has consistently delivered exceptional results.
Throughout his career, he has taken on multifaceted roles, from leading technical project management teams to owning solutions that drive operational excellence. His conscientious and proactive approach is unwavering, whether he is working independently or collaboratively within a team. His ability to connect with colleagues on a personal level underscores his commitment to fostering a harmonious and productive workplace environment.
Date: May 29, 2024
Tags: Information Security, ISO/IEC 27001, ISO/IEC 42001, Artificial Intelligence, GDPR
-------------------------------------------------------------------------------
Find out more about ISO training and certification services
Training: ISO/IEC 27001 Information Security Management System - EN | PECB
ISO/IEC 42001 Artificial Intelligence Management System - EN | PECB
General Data Protection Regulation (GDPR) - Training Courses - EN | PECB
Webinars: https://pecb.com/webinars
Article: https://pecb.com/article
-------------------------------------------------------------------------------
For more information about PECB:
Website: https://pecb.com/
LinkedIn: https://www.linkedin.com/company/pecb/
Facebook: https://www.facebook.com/PECBInternational/
Slideshare: http://www.slideshare.net/PECBCERTIFICATION
Pollock and Snow "DEIA in the Scholarly Landscape, Session One: Setting Expec...
Pollock and Snow "DEIA in the Scholarly Landscape, Session One: Setting Expec...National Information Standards Organization (NISO)
This presentation was provided by Steph Pollock of The American Psychological Association’s Journals Program, and Damita Snow, of The American Society of Civil Engineers (ASCE), for the initial session of NISO's 2024 Training Series "DEIA in the Scholarly Landscape." Session One: 'Setting Expectations: a DEIA Primer,' was held June 6, 2024.How to Manage Your Lost Opportunities in Odoo 17 CRM
Odoo 17 CRM allows us to track why we lose sales opportunities with "Lost Reasons." This helps analyze our sales process and identify areas for improvement. Here's how to configure lost reasons in Odoo 17 CRM
Wound healing PPT
This document provides an overview of wound healing, its functions, stages, mechanisms, factors affecting it, and complications.
A wound is a break in the integrity of the skin or tissues, which may be associated with disruption of the structure and function.
Healing is the body’s response to injury in an attempt to restore normal structure and functions.
Healing can occur in two ways: Regeneration and Repair
There are 4 phases of wound healing: hemostasis, inflammation, proliferation, and remodeling. This document also describes the mechanism of wound healing. Factors that affect healing include infection, uncontrolled diabetes, poor nutrition, age, anemia, the presence of foreign bodies, etc.
Complications of wound healing like infection, hyperpigmentation of scar, contractures, and keloid formation.
How to Make a Field Mandatory in Odoo 17
In Odoo, making a field required can be done through both Python code and XML views. When you set the required attribute to True in Python code, it makes the field required across all views where it's used. Conversely, when you set the required attribute in XML views, it makes the field required only in the context of that particular view.
RHEOLOGY Physical pharmaceutics-II notes for B.pharm 4th sem students
Physical pharmaceutics notes for B.pharm students
How to Create a More Engaging and Human Online Learning Experience
How to Create a More Engaging and Human Online Learning Experience Wahiba Chair Training & Consulting
Wahiba Chair's Talk at the 2024 Learning Ideas Conference. ANATOMY AND BIOMECHANICS OF HIP JOINT.pdf
it describes the bony anatomy including the femoral head , acetabulum, labrum . also discusses the capsule , ligaments . muscle that act on the hip joint and the range of motion are outlined. factors affecting hip joint stability and weight transmission through the joint are summarized.
Recently uploaded (20)
NEWSPAPERS - QUESTION 1 - REVISION POWERPOINT.pptx
NEWSPAPERS - QUESTION 1 - REVISION POWERPOINT.pptx
বাংলাদেশ অর্থনৈতিক সমীক্ষা (Economic Review) ২০২৪ UJS App.pdf
বাংলাদেশ অর্থনৈতিক সমীক্ষা (Economic Review) ২০২৪ UJS App.pdf
South African Journal of Science: Writing with integrity workshop (2024)
South African Journal of Science: Writing with integrity workshop (2024)
Digital Artefact 1 - Tiny Home Environmental Design
Digital Artefact 1 - Tiny Home Environmental Design
BÀI TẬP DẠY THÊM TIẾNG ANH LỚP 7 CẢ NĂM FRIENDS PLUS SÁCH CHÂN TRỜI SÁNG TẠO ...
BÀI TẬP DẠY THÊM TIẾNG ANH LỚP 7 CẢ NĂM FRIENDS PLUS SÁCH CHÂN TRỜI SÁNG TẠO ...
BÀI TẬP BỔ TRỢ TIẾNG ANH 8 CẢ NĂM - GLOBAL SUCCESS - NĂM HỌC 2023-2024 (CÓ FI...
BÀI TẬP BỔ TRỢ TIẾNG ANH 8 CẢ NĂM - GLOBAL SUCCESS - NĂM HỌC 2023-2024 (CÓ FI...
BÀI TẬP BỔ TRỢ TIẾNG ANH LỚP 9 CẢ NĂM - GLOBAL SUCCESS - NĂM HỌC 2024-2025 - ...
BÀI TẬP BỔ TRỢ TIẾNG ANH LỚP 9 CẢ NĂM - GLOBAL SUCCESS - NĂM HỌC 2024-2025 - ...
ISO/IEC 27001, ISO/IEC 42001, and GDPR: Best Practices for Implementation and...
ISO/IEC 27001, ISO/IEC 42001, and GDPR: Best Practices for Implementation and...
Pollock and Snow "DEIA in the Scholarly Landscape, Session One: Setting Expec...
Pollock and Snow "DEIA in the Scholarly Landscape, Session One: Setting Expec...
How to Manage Your Lost Opportunities in Odoo 17 CRM
How to Manage Your Lost Opportunities in Odoo 17 CRM
RHEOLOGY Physical pharmaceutics-II notes for B.pharm 4th sem students
RHEOLOGY Physical pharmaceutics-II notes for B.pharm 4th sem students
How to Create a More Engaging and Human Online Learning Experience
How to Create a More Engaging and Human Online Learning Experience
Channel assignment strategies
- 2. Channel Assignment Goals: • achieve high spectrum utilization • maintain a given service quality • use a simple algorithm • require a minimum number of database lookups – Unfortunately it is hard to do all of these at once! – If there is no available channel, then • new calls are blocked • existing calls that can’t be handed over - forced terminations
- 3. Channel Assignment Process • Fixed Channel Assignment (FCA) • Dynamic Channel Assignment (DCA) • Quasi-static autonomous frequency assignment (QSAFA) • Lots of schemes have been introduced to reduce the number of forced terminations, at the cost of increased blocking or decreased efficiency:
- 4. Channel Assignment Strategies • Fixed channel assignment – each cell is allocated a predetermined set of voice channel – any new call attempt can only be served by the unused channels – the call will be blocked if all channels in that cell are occupied • Dynamic channel assignment – channels are not allocated to cells permanently. – BSC requests channel from MSC to allocate channel when call initiate. – reduce the likelihood of blocking, increase capacity. – MSC allocates channel to call based on algorithm that takes into account • Probability of future blocking within cell – MSC assigns channel that will not interfere with existing calls – Reduces probability of blocking &Increases channel utilization Frequency reuse scheme Channel assignment strategy • increases capacity • minimize interference • fixed channel assignment • dynamic channel assignment
- 5. Channel Assignment Process • Nonprioritized scheme (NPS) - handoff call treated the same as a new call. • Reserved Channel scheme (RCS)- reserves some resources for handoffs. • Queuing Priority scheme (QPS) - exploit the over lap (handoff area). • Sub rating scheme (SRS) - switching CODECs of one or more callsto free resources.
- 6. 6 Typical call • Mobile unit initialization – Scan and select strongest set up control channel – Automatically selected BS antenna of cell • Usually but not always nearest (propagation environment) – Handshake to identify user and register location – Scan repeated to allow for movement • Change of cell – Mobile unit monitors for pages (see below) • Mobile originated call – Check set up channel is free • Monitor forward channel (from BS) and wait for idle – Send number on pre-selected channel
- 7. 7 Typical call… Paging – MSC attempts to connect to mobile unit – Paging message sent to BSs depending on called mobile number – Paging signal transmitted on set up channel Call accepted – Mobile unit recognizes number on set up channel – Responds to BS which sends response to MSC – MSC sets up circuit between calling and called BSs – MSC selects available traffic channel within cells and notifies BSs – BSs notify mobile unit of channel
- 8. 8 Typical call… • Ongoing call – Voice/data exchanged through respective BSs and MSC • Handoff – Mobile unit moves out of range of cell into range of another cell – Traffic channel changes to one assigned to new BS • Without interruption of service to user
- 9. 9 Power Control • If MS is near the BS or in LOS situation, power to/from the MS can be reduced – Helps Reduce CCI – Save battery power – Alleviate health concerns • Coarse power control is adequate – Implemented through Open Loop Power Control • In CDMA systems all MS use same frequency • Fine power control is crucial to mitigate the near-far effect – Both Open & Closed Loop Power Control
- 10. 10 Cellular System Channels • Control channels – Forward and Reverse – Setting up and maintaining calls – Exchange commands an/or messages between MS and BS or MSC (as needed) • Traffic channels – Carry voice and/or data traffic