1) Multibeam antennas can provide cost-efficient capacity gains but their deployment introduces new planning challenges like coverage gaps and physical cell identity (PCI) conflicts.
2) Coverage gaps may arise after upgrading to multibeam antennas if beam directions are not properly adjusted. Rotating all sectors by 10-20 degrees can eliminate gaps.
3) PCI planning is more complex with multibeam antennas due to limitations of PCI modulo 3 for reference signal allocation. Proper grouping of PCI values within and between sites can help mitigate conflicts.
This white paper discusses the migration from DVB-S to DVB-S2 satellite communication standards and the related efficiencies. DVB-S2 provides improved forward error correction using LDPC coding, which allows for a 30% increase in bandwidth efficiency over DVB-S. This efficiency gain can be used to support more users within an existing bandwidth allocation or reduce the bandwidth needed to support the same number of users. The paper provides an example where migrating from DVB-S to DVB-S2 reduces the monthly operating expense for a satellite transmission by 30% by needing less bandwidth to support all users within the satellite footprint.
This document discusses various MIMO techniques including single-user and multi-user MIMO. It begins with an overview of STBC, which is used in 802.11ac and provides transmit diversity with low cost. Spatial multiplexing allows multiple parallel channels to improve throughput. For single-user MIMO, transmit beamforming enhances signal reception through precoding techniques like SVD that establish parallel channels. Multi-user MIMO further increases capacity but introduces interference that must be managed through precoding and receiver techniques like zero-forcing. Channel feedback is also required to implement beamforming and precoding.
Signal Alignment: Enabling Physical Layer Network Coding for MIMO NetworkingAishwary Singh
This document discusses physical layer network coding with signal alignment (PNC-SA) for improving transmission strategies in two-way relay channels. It explains how PNC-SA allows multiple packets to be simultaneously transmitted and received through precoding vectors that align signals at access points. The document compares the bit error rate and throughput of PNC-SA to other techniques. It also explores applications of PNC-SA like information exchange, cross unicasts, multi-sender multicast, and multi-hop broadcast in MIMO wireless networks.
Multiuser MIMO-OFDM simulation framework in MatlabPavel Loskot
Simulation framework for multiuser MIMO-OFDM over multipath fading channels. Also created a C-like pre-processor in Matlab to add flexibility in configuring the simulation prior its run.
BER Performance of OFDM-QAM over AWGN and RICAIN Channels Using Error Correct...IJERA Editor
In this paper, the performance of OFDM - QAM system by using error correcting codes (Convolutional, Reed Solomon and Interleaving) schemes that are used to encode the data stream in wireless communications using AWGN and RICIAN channels has been reported here. OFDM is presented for wireless communications we curing basic OFDM and affined modulations, as well as techniques to improve the performance of OFDM for wireless communications. Various simulations are performed to detect the best BER performance of each of the QAM system; OFDM-QAM and OFDM-QAM with Error Correction and to use the best outcomes to model the OFDM-QAM, Their effect of improving the total BER can be noticed due to the benefits of OFDM-QAM with correcting codes.
SONET and SDH are standards for synchronous optical networking. They were developed to address limitations in earlier PDH digital telephony networks, such as increasing overhead percentages and lack of interoperability between regional systems. SONET/SDH uses a layered architecture with standardized rates and frame structures. It defines optical, line, and path layers to transport digital signals end-to-end with integrated operations, administration, and maintenance capabilities. This allows flexible and efficient transport of diverse payloads, including PDH, ATM, and packet data, over optical networks on a global scale.
1) Researchers at JPL developed a compact digital radar receiver to be used in a Ka-band radar interferometer for ice surface topography mapping.
2) The receiver is designed to be flexible and compact to meet the needs of a 16-element digital beamforming system while also being adaptable to other applications.
3) It can sample RF inputs up to 3.3 GHz at 10 bits and extract data via a front-panel interface, with components selected for potential spaceborne use.
Localization in V2X Communication NetworksStefano Severi
Presentation made by Alireza Ghods and given by Dr. Stefano Severi at CCP Workshop co-located with IEEE Intelligent Vehicles Conference, 19th June 2016 Gothenburg (Sweden)
This white paper discusses the migration from DVB-S to DVB-S2 satellite communication standards and the related efficiencies. DVB-S2 provides improved forward error correction using LDPC coding, which allows for a 30% increase in bandwidth efficiency over DVB-S. This efficiency gain can be used to support more users within an existing bandwidth allocation or reduce the bandwidth needed to support the same number of users. The paper provides an example where migrating from DVB-S to DVB-S2 reduces the monthly operating expense for a satellite transmission by 30% by needing less bandwidth to support all users within the satellite footprint.
This document discusses various MIMO techniques including single-user and multi-user MIMO. It begins with an overview of STBC, which is used in 802.11ac and provides transmit diversity with low cost. Spatial multiplexing allows multiple parallel channels to improve throughput. For single-user MIMO, transmit beamforming enhances signal reception through precoding techniques like SVD that establish parallel channels. Multi-user MIMO further increases capacity but introduces interference that must be managed through precoding and receiver techniques like zero-forcing. Channel feedback is also required to implement beamforming and precoding.
Signal Alignment: Enabling Physical Layer Network Coding for MIMO NetworkingAishwary Singh
This document discusses physical layer network coding with signal alignment (PNC-SA) for improving transmission strategies in two-way relay channels. It explains how PNC-SA allows multiple packets to be simultaneously transmitted and received through precoding vectors that align signals at access points. The document compares the bit error rate and throughput of PNC-SA to other techniques. It also explores applications of PNC-SA like information exchange, cross unicasts, multi-sender multicast, and multi-hop broadcast in MIMO wireless networks.
Multiuser MIMO-OFDM simulation framework in MatlabPavel Loskot
Simulation framework for multiuser MIMO-OFDM over multipath fading channels. Also created a C-like pre-processor in Matlab to add flexibility in configuring the simulation prior its run.
BER Performance of OFDM-QAM over AWGN and RICAIN Channels Using Error Correct...IJERA Editor
In this paper, the performance of OFDM - QAM system by using error correcting codes (Convolutional, Reed Solomon and Interleaving) schemes that are used to encode the data stream in wireless communications using AWGN and RICIAN channels has been reported here. OFDM is presented for wireless communications we curing basic OFDM and affined modulations, as well as techniques to improve the performance of OFDM for wireless communications. Various simulations are performed to detect the best BER performance of each of the QAM system; OFDM-QAM and OFDM-QAM with Error Correction and to use the best outcomes to model the OFDM-QAM, Their effect of improving the total BER can be noticed due to the benefits of OFDM-QAM with correcting codes.
SONET and SDH are standards for synchronous optical networking. They were developed to address limitations in earlier PDH digital telephony networks, such as increasing overhead percentages and lack of interoperability between regional systems. SONET/SDH uses a layered architecture with standardized rates and frame structures. It defines optical, line, and path layers to transport digital signals end-to-end with integrated operations, administration, and maintenance capabilities. This allows flexible and efficient transport of diverse payloads, including PDH, ATM, and packet data, over optical networks on a global scale.
1) Researchers at JPL developed a compact digital radar receiver to be used in a Ka-band radar interferometer for ice surface topography mapping.
2) The receiver is designed to be flexible and compact to meet the needs of a 16-element digital beamforming system while also being adaptable to other applications.
3) It can sample RF inputs up to 3.3 GHz at 10 bits and extract data via a front-panel interface, with components selected for potential spaceborne use.
Localization in V2X Communication NetworksStefano Severi
Presentation made by Alireza Ghods and given by Dr. Stefano Severi at CCP Workshop co-located with IEEE Intelligent Vehicles Conference, 19th June 2016 Gothenburg (Sweden)
The document discusses the differences between SDH and PDH, as well as key aspects of SDH. SDH provides higher transmission rates up to 40 Gbit/s, simplified add and drop functions, high availability and capacity matching, reliability, and is a future-proof platform for new services compared to PDH. SDH uses synchronous multiplexing where data from multiple sources is byte interleaved at fixed locations in the frame. This allows single channels to be dropped from the data stream without demultiplexing intermediate rates as required in PDH.
Second screen prototype for broadcasted digital tv users in ISDB-Tb StandardAndy Juan Sarango Veliz
This document proposes a second screen solution for users of the Brazilian Digital Television System (SBTVD/ISDB-Tb) that allows accessing additional synchronized content related to broadcast programs through mobile devices. It describes an architecture using a transmission protocol to carry information allowing digital TV receivers to communicate with nearby second screen devices running a dedicated application. This would provide users with limited resources the ability to access additional live broadcast program information, opening opportunities for broadcasters and users. A prototype was developed including a TV receiver simulation and mobile app to identify and present interactive synchronized content.
This document provides an overview of LTE vs 3G technologies. It discusses LTE's motivations including higher data rates and spectral efficiency. It covers MIMO definitions and how to calculate LTE and 3G throughput. It also compares the architectures, access technologies, physical resources, frames, and channels of LTE, 3G, and 2G. Key aspects of LTE performance are highlighted such as scalable bandwidth and flat IP architecture.
Channel coding transforms binary data bits into signal elements that can be transmitted. It involves selecting a coding scheme to avoid high frequencies, direct current, and ensure timing control. Common line codes include alternate mark inversion (AMI), high-density bipolar three zeros (HDB3), and coded mark inverted (CMI). These codes ensure sufficient transitions to maintain synchronization and embed timing information while removing the dc component.
Design simulation and evaluation of siso miso mimo ofdm systemsIJLT EMAS
In this paper an endeavour is made to design and simulate SISO, MISO and MIMO OFDM systems. We have analysed and compared the performance of these systems for image transmission over AWGN and Rayleigh channels. The effect of LS channel estimation on the BER over a range of SNR for MIMO(2X2) systems is examined. We have also compared the performance based on various M-ary PSK modulation techniques for image transmission over Rayleigh channel in MIMO-OFDM system. The system performance is simulated in Matlab. The results of the simulation show that as the antenna diversity increases, the BER decreases and the channel capacity increases. Also, the BER obtained in MIMO-OFDM system is less when LS estimation is used.
The document provides an overview of SONET (Synchronous Optical Networking) and SDH (Synchronous Digital Hierarchy) architectures and technologies. It describes the four layers of SONET (path, line, section, photonic), SONET frame structure including overhead bytes, and how lower-rate STS frames are multiplexed into higher-rate frames. It also discusses different types of SONET networks including linear, ring and mesh, as well as the use of virtual tributaries to transport digital signals of different rates over SONET.
This document describes the design and implementation of a QAM transmitter and receiver using an FPGA. It includes:
1) A block diagram and description of the QAM transmitter design including a data sampler, phase accumulator, symbol mapper, and NCO.
2) A block diagram and description of the QAM receiver design including a phase locked loop, symbol demapper, and clock distributor.
3) Details on the carrier synchronization and timing synchronization implemented, including a phase locked loop with a phase accumulator used for carrier recovery.
4) Simulation results showing the design was successfully simulated, synthesized for an FPGA, and verified on an FPGA board.
Synchronous Optical Networking (SONET) and Synchronous Digital Hierarchy (SDH) are standardized protocols that transfer multiple digital bit streams synchronously over optical fiber using lasers or LEDs. SONET was developed to replace earlier asynchronous systems for transporting large amounts of telephone calls and data traffic over fiber without synchronization problems. SONET defines four layers - path, line, section, and photonic - to move signals across the network. It also defines a hierarchy of electrical signaling levels called STSs and corresponding optical signals called OCs. SONET networks can be configured in point-to-point, multipoint, ring or mesh topologies and provide advantages like reduced complexity, protection, bandwidth efficiency
Here are the key points about Frame Relay and SONET/SDH:
Frame Relay:
- Frame relay is a standardized wide-area data networking technology that implements standards-based protocols.
- It is a packet switching protocol and operates at the physical and data link layer (layers 1 and 2) of the OSI model.
- Frame relay networks allow sharing of bandwidth and routes among multiple applications and users.
SONET/SDH:
- SONET is a telecommunications standard for synchronous data transmission on optical media. It was developed by ANSI.
- SDH is the international counterpart to SONET, developed by ITU-T. Though independent, they are fundamentally similar and
The document discusses MIMO (Multiple Input Multiple Output) systems. It motivates MIMO by explaining how system designers aim to achieve high data rates and quality while minimizing complexity, transmission power, and bandwidth. It describes MIMO antenna configurations including SISO and MIMO. MIMO systems use multiple transmit and receive antennas to achieve high capacity. The document outlines diversity as a design criterion for MIMO systems to achieve reliable reception. It also discusses Alamouti's space-time coding scheme and how MIMO can be combined with OFDM to further improve performance. In conclusions, MIMO brings us closer to gigabit speeds while also providing reliable communications.
A cube sat communication design for In-Space Assembly Ensaf Atef
A nuclear power plant is a thermal power station in which the heat source is a nuclear reactor. As is typical in all conventional thermal power stations the heat is used to generate steam which drives a steam turbine connected to a generator which produces electricity. The conversion to electrical energy takes place indirectly, as in conventional thermal power plants.
This document discusses encoding techniques used for Dedicated Short Range Communication (DSRC) applications. It describes Flexible Macroblock Ordering (FMO) encoding and Manchester encoding. It presents the hardware architectures for FMO and Manchester encoders and discusses how the Similarity Oriented Logic Simplification (SOLS) technique is used to integrate the logic, reducing transistors and achieving 100% hardware utilization. The SOLS techniques eliminate limitations in the hardware architectures to improve efficiency.
This document summarizes a presentation on carrier frequency offset estimation for non-contiguous OFDM receivers in cognitive radio systems. It discusses:
1) The system model of cognitive radio and non-contiguous OFDM, the importance of carrier frequency offset estimation, and a proposed scheme using hard-decision-based active subchannel detection and maximum likelihood estimation to estimate the offset.
2) Simulation results showing the mean square estimation error compared to the Cramer-Rao lower bound over a range of signal to noise and interference ratios and active subchannel ratios.
3) The conclusion that the proposed scheme achieves similar estimation accuracy to the theoretical lower bound over a broad range of conditions, enabling spectrum synchronization information extraction and received code bit
Fully reused vlsi architecture of fm0 manchester encoding using sols techniqu...LogicMindtech Nologies
VLSI Projects for M. Tech, VLSI Projects in Vijayanagar, VLSI Projects in Bangalore, M. Tech Projects in Vijayanagar, M. Tech Projects in Bangalore, VLSI IEEE projects in Bangalore, IEEE 2015 VLSI Projects, FPGA and Xilinx Projects, FPGA and Xilinx Projects in Bangalore, FPGA and Xilinx Projects in Vijayangar
The document discusses strategies for selecting IBS carriers for a second layer to increase capacity. It evaluates two options: using F1 and F2 carriers, or F1 and F3 carriers. It recommends using F1 and F2 for the project as most sites will be upgraded to three layers, and this option is simpler to set up while providing similar performance to using F1 and F3. It then covers mobility, neighbor planning, radio features, and cell ID planning considerations for the two-carrier IBS configuration.
Telecommunication System Engineering NotesHaris Hassan
Telecommunications engineering, or telecoms engineering, is an engineering discipline centered on electrical and computer engineering which seeks to support and enhance telecommunication systems.
09 Using Telephone_and_Cable_Networks_for_Data_TransmissionAhmar Hashmi
This document discusses using telephone and cable networks for data transmission. It covers telephone networks using circuit switching to transmit analog voice signals over copper wires. It describes components like local exchange carriers and signaling networks. It also covers using telephone lines for data transmission through dial-up modems and digital subscriber line (DSL) technologies. Finally, it discusses cable TV networks evolving from unidirectional video to bidirectional hybrid fiber-coaxial (HFC) networks capable of high-speed data transmission using standards like DOCSIS.
TV Repack & ATSC 3.0: SFN & Future proofing antennaskmsavage
This document summarizes a presentation about planning for TV repack and futureproofing antennas for ATSC 3.0. It discusses the incentive auction timeline, how many stations will be directly impacted, the process for stations moving to new channels after the auction. It covers considerations for antennas on lower channels like needing larger/heavier antennas. It also discusses futureproofing antennas for ATSC 3.0 like adding more null fill or making antennas compatible with single frequency networks. Signal strength requirements for different types of services are presented. Network planning assumptions and an example for a station in Baltimore are provided.
The document discusses the frame structure of Synchronous Digital Hierarchy (SDH). It explains that an SDH frame is transmitted every 125 microseconds and contains 9 rows and 270 columns of bytes for a total of 19,440 bits. This equates to a basic data rate of 155.52 megabits per second. The frame contains sections for regenerator and multiplexer section overhead as well as a payload area. Lower level signals can be mapped and multiplexed into the payload area through a process that includes mapping, aligning, pointer processing and multiplexing.
This document discusses Synchronous Optical Networking (SONET), a telecommunications standard that defines a set of fiber-optic transmission rates. It describes how SONET simplifies and standardizes time-division multiplexing and its hierarchical structure. Key aspects covered include the SONET frame format, multiplexing layers of section, line, and path, and how payloads are interleaved and framed for transmission.
This article discusses the high-level design principles behind 5G antenna array architecture MIMO and beamforming technology to meet the requirements of 5G NR systems.
The higher the carrier frequency, the path loss will increase significantly relative to the fixed antenna size of the wavelength. A smaller antenna size at a higher carrier frequency means that more antennas are installed in the same area.
The path loss caused by the increase in carrier frequency can be overcome by using more antennas without increasing the overall physical size of the 5G antenna array.
In addition, when the carrier frequency increases above about 10 GHz, diffraction will no longer be the main propagation mechanism. Above 10Ghz, reflection and scattering will be the most important transmission mechanisms for non-line-of-sight transmission links.
Simulation of Wimax 802.16E Physical LayermodelIOSR Journals
This document summarizes a simulation of the physical layer of WiMAX 802.16e. It describes the design of a WiMAX PHY layer transmitter and receiver model using MATLAB. The model uses 16-QAM modulation over OFDM with 256 subcarriers. Performance is analyzed by transmitting data over AWGN and Rayleigh fading channels and measuring bit loss and packet loss versus SNR and signal power. The results show that bit loss decreases with increasing SNR and decreasing signal power. A combination of SNR=13dB and signal power of 0.6W provided zero bit loss.
The document discusses the differences between SDH and PDH, as well as key aspects of SDH. SDH provides higher transmission rates up to 40 Gbit/s, simplified add and drop functions, high availability and capacity matching, reliability, and is a future-proof platform for new services compared to PDH. SDH uses synchronous multiplexing where data from multiple sources is byte interleaved at fixed locations in the frame. This allows single channels to be dropped from the data stream without demultiplexing intermediate rates as required in PDH.
Second screen prototype for broadcasted digital tv users in ISDB-Tb StandardAndy Juan Sarango Veliz
This document proposes a second screen solution for users of the Brazilian Digital Television System (SBTVD/ISDB-Tb) that allows accessing additional synchronized content related to broadcast programs through mobile devices. It describes an architecture using a transmission protocol to carry information allowing digital TV receivers to communicate with nearby second screen devices running a dedicated application. This would provide users with limited resources the ability to access additional live broadcast program information, opening opportunities for broadcasters and users. A prototype was developed including a TV receiver simulation and mobile app to identify and present interactive synchronized content.
This document provides an overview of LTE vs 3G technologies. It discusses LTE's motivations including higher data rates and spectral efficiency. It covers MIMO definitions and how to calculate LTE and 3G throughput. It also compares the architectures, access technologies, physical resources, frames, and channels of LTE, 3G, and 2G. Key aspects of LTE performance are highlighted such as scalable bandwidth and flat IP architecture.
Channel coding transforms binary data bits into signal elements that can be transmitted. It involves selecting a coding scheme to avoid high frequencies, direct current, and ensure timing control. Common line codes include alternate mark inversion (AMI), high-density bipolar three zeros (HDB3), and coded mark inverted (CMI). These codes ensure sufficient transitions to maintain synchronization and embed timing information while removing the dc component.
Design simulation and evaluation of siso miso mimo ofdm systemsIJLT EMAS
In this paper an endeavour is made to design and simulate SISO, MISO and MIMO OFDM systems. We have analysed and compared the performance of these systems for image transmission over AWGN and Rayleigh channels. The effect of LS channel estimation on the BER over a range of SNR for MIMO(2X2) systems is examined. We have also compared the performance based on various M-ary PSK modulation techniques for image transmission over Rayleigh channel in MIMO-OFDM system. The system performance is simulated in Matlab. The results of the simulation show that as the antenna diversity increases, the BER decreases and the channel capacity increases. Also, the BER obtained in MIMO-OFDM system is less when LS estimation is used.
The document provides an overview of SONET (Synchronous Optical Networking) and SDH (Synchronous Digital Hierarchy) architectures and technologies. It describes the four layers of SONET (path, line, section, photonic), SONET frame structure including overhead bytes, and how lower-rate STS frames are multiplexed into higher-rate frames. It also discusses different types of SONET networks including linear, ring and mesh, as well as the use of virtual tributaries to transport digital signals of different rates over SONET.
This document describes the design and implementation of a QAM transmitter and receiver using an FPGA. It includes:
1) A block diagram and description of the QAM transmitter design including a data sampler, phase accumulator, symbol mapper, and NCO.
2) A block diagram and description of the QAM receiver design including a phase locked loop, symbol demapper, and clock distributor.
3) Details on the carrier synchronization and timing synchronization implemented, including a phase locked loop with a phase accumulator used for carrier recovery.
4) Simulation results showing the design was successfully simulated, synthesized for an FPGA, and verified on an FPGA board.
Synchronous Optical Networking (SONET) and Synchronous Digital Hierarchy (SDH) are standardized protocols that transfer multiple digital bit streams synchronously over optical fiber using lasers or LEDs. SONET was developed to replace earlier asynchronous systems for transporting large amounts of telephone calls and data traffic over fiber without synchronization problems. SONET defines four layers - path, line, section, and photonic - to move signals across the network. It also defines a hierarchy of electrical signaling levels called STSs and corresponding optical signals called OCs. SONET networks can be configured in point-to-point, multipoint, ring or mesh topologies and provide advantages like reduced complexity, protection, bandwidth efficiency
Here are the key points about Frame Relay and SONET/SDH:
Frame Relay:
- Frame relay is a standardized wide-area data networking technology that implements standards-based protocols.
- It is a packet switching protocol and operates at the physical and data link layer (layers 1 and 2) of the OSI model.
- Frame relay networks allow sharing of bandwidth and routes among multiple applications and users.
SONET/SDH:
- SONET is a telecommunications standard for synchronous data transmission on optical media. It was developed by ANSI.
- SDH is the international counterpart to SONET, developed by ITU-T. Though independent, they are fundamentally similar and
The document discusses MIMO (Multiple Input Multiple Output) systems. It motivates MIMO by explaining how system designers aim to achieve high data rates and quality while minimizing complexity, transmission power, and bandwidth. It describes MIMO antenna configurations including SISO and MIMO. MIMO systems use multiple transmit and receive antennas to achieve high capacity. The document outlines diversity as a design criterion for MIMO systems to achieve reliable reception. It also discusses Alamouti's space-time coding scheme and how MIMO can be combined with OFDM to further improve performance. In conclusions, MIMO brings us closer to gigabit speeds while also providing reliable communications.
A cube sat communication design for In-Space Assembly Ensaf Atef
A nuclear power plant is a thermal power station in which the heat source is a nuclear reactor. As is typical in all conventional thermal power stations the heat is used to generate steam which drives a steam turbine connected to a generator which produces electricity. The conversion to electrical energy takes place indirectly, as in conventional thermal power plants.
This document discusses encoding techniques used for Dedicated Short Range Communication (DSRC) applications. It describes Flexible Macroblock Ordering (FMO) encoding and Manchester encoding. It presents the hardware architectures for FMO and Manchester encoders and discusses how the Similarity Oriented Logic Simplification (SOLS) technique is used to integrate the logic, reducing transistors and achieving 100% hardware utilization. The SOLS techniques eliminate limitations in the hardware architectures to improve efficiency.
This document summarizes a presentation on carrier frequency offset estimation for non-contiguous OFDM receivers in cognitive radio systems. It discusses:
1) The system model of cognitive radio and non-contiguous OFDM, the importance of carrier frequency offset estimation, and a proposed scheme using hard-decision-based active subchannel detection and maximum likelihood estimation to estimate the offset.
2) Simulation results showing the mean square estimation error compared to the Cramer-Rao lower bound over a range of signal to noise and interference ratios and active subchannel ratios.
3) The conclusion that the proposed scheme achieves similar estimation accuracy to the theoretical lower bound over a broad range of conditions, enabling spectrum synchronization information extraction and received code bit
Fully reused vlsi architecture of fm0 manchester encoding using sols techniqu...LogicMindtech Nologies
VLSI Projects for M. Tech, VLSI Projects in Vijayanagar, VLSI Projects in Bangalore, M. Tech Projects in Vijayanagar, M. Tech Projects in Bangalore, VLSI IEEE projects in Bangalore, IEEE 2015 VLSI Projects, FPGA and Xilinx Projects, FPGA and Xilinx Projects in Bangalore, FPGA and Xilinx Projects in Vijayangar
The document discusses strategies for selecting IBS carriers for a second layer to increase capacity. It evaluates two options: using F1 and F2 carriers, or F1 and F3 carriers. It recommends using F1 and F2 for the project as most sites will be upgraded to three layers, and this option is simpler to set up while providing similar performance to using F1 and F3. It then covers mobility, neighbor planning, radio features, and cell ID planning considerations for the two-carrier IBS configuration.
Telecommunication System Engineering NotesHaris Hassan
Telecommunications engineering, or telecoms engineering, is an engineering discipline centered on electrical and computer engineering which seeks to support and enhance telecommunication systems.
09 Using Telephone_and_Cable_Networks_for_Data_TransmissionAhmar Hashmi
This document discusses using telephone and cable networks for data transmission. It covers telephone networks using circuit switching to transmit analog voice signals over copper wires. It describes components like local exchange carriers and signaling networks. It also covers using telephone lines for data transmission through dial-up modems and digital subscriber line (DSL) technologies. Finally, it discusses cable TV networks evolving from unidirectional video to bidirectional hybrid fiber-coaxial (HFC) networks capable of high-speed data transmission using standards like DOCSIS.
TV Repack & ATSC 3.0: SFN & Future proofing antennaskmsavage
This document summarizes a presentation about planning for TV repack and futureproofing antennas for ATSC 3.0. It discusses the incentive auction timeline, how many stations will be directly impacted, the process for stations moving to new channels after the auction. It covers considerations for antennas on lower channels like needing larger/heavier antennas. It also discusses futureproofing antennas for ATSC 3.0 like adding more null fill or making antennas compatible with single frequency networks. Signal strength requirements for different types of services are presented. Network planning assumptions and an example for a station in Baltimore are provided.
The document discusses the frame structure of Synchronous Digital Hierarchy (SDH). It explains that an SDH frame is transmitted every 125 microseconds and contains 9 rows and 270 columns of bytes for a total of 19,440 bits. This equates to a basic data rate of 155.52 megabits per second. The frame contains sections for regenerator and multiplexer section overhead as well as a payload area. Lower level signals can be mapped and multiplexed into the payload area through a process that includes mapping, aligning, pointer processing and multiplexing.
This document discusses Synchronous Optical Networking (SONET), a telecommunications standard that defines a set of fiber-optic transmission rates. It describes how SONET simplifies and standardizes time-division multiplexing and its hierarchical structure. Key aspects covered include the SONET frame format, multiplexing layers of section, line, and path, and how payloads are interleaved and framed for transmission.
This article discusses the high-level design principles behind 5G antenna array architecture MIMO and beamforming technology to meet the requirements of 5G NR systems.
The higher the carrier frequency, the path loss will increase significantly relative to the fixed antenna size of the wavelength. A smaller antenna size at a higher carrier frequency means that more antennas are installed in the same area.
The path loss caused by the increase in carrier frequency can be overcome by using more antennas without increasing the overall physical size of the 5G antenna array.
In addition, when the carrier frequency increases above about 10 GHz, diffraction will no longer be the main propagation mechanism. Above 10Ghz, reflection and scattering will be the most important transmission mechanisms for non-line-of-sight transmission links.
Simulation of Wimax 802.16E Physical LayermodelIOSR Journals
This document summarizes a simulation of the physical layer of WiMAX 802.16e. It describes the design of a WiMAX PHY layer transmitter and receiver model using MATLAB. The model uses 16-QAM modulation over OFDM with 256 subcarriers. Performance is analyzed by transmitting data over AWGN and Rayleigh fading channels and measuring bit loss and packet loss versus SNR and signal power. The results show that bit loss decreases with increasing SNR and decreasing signal power. A combination of SNR=13dB and signal power of 0.6W provided zero bit loss.
The document outlines the procedure for CDMA network design in 5 stages:
1. Preparations including setting design criteria like coverage reliability, capacity, and soft handoff ratios.
2. RF environment analysis involving region clustering, site surveys, competitor analysis, and link budget analysis.
3. Coverage design for outdoor, indoor, and underground areas.
4. Parameter design including pilot assignment and base station dimensioning.
5. Reporting and dimensioning to determine equipment requirements.
A Novel Carrier Indexing Method for Side Lobe Suppression and Bit Error Rate ...IRJET Journal
This paper proposes a novel carrier indexing method using variable basis functions to suppress side lobes and reduce bit error rates in non-continuous OFDM (NC-OFDM) systems. Existing active interference cancellation techniques used fixed-length rectangular basis functions for cancellation carriers, which were not optimal. The proposed method groups cancellation carriers by frequency position and shapes them with variable-length waveforms to more effectively suppress NC-OFDM side lobes while reducing inter-carrier interference. Simulation results show the proposed approach achieves over 80dB side lobe reduction and negligible inter-carrier interference compared to existing techniques. The method provides reliable data transmission between primary and secondary nodes in cognitive radio networks with lower bit error rates.
The most important RF technology change in 5G NR is the application of 3D-MIMO large-scale array antenna technology so that a considerable part of the NR physical layer architecture design content is adapted and updated around the technology. Here is a comparative perspective on the 5G system. 3D-MIMO antenna technology is introduced.
A reconfigurable dual port antenna system for underlay/interweave cognitive ...IJECEIAES
An antenna system that is reconfigurable in frequency is presented in this paper as a novel dual port design that serves both undelay and interweave cognitive radio. This 25×40×0.8 mm3 system is composed of two wide slot antennas: the first is designed as an ultra-wideband (UWB) antenna with controllable band rejection capabilities, while the second antenna is reconfigurable for communication purposes. Three slots are etched into the patch of the UWB antenna to obtain band notching in wireless local area network/Xband/International Telecommunication Union bands (WLAN/Xband/ITU) bands which can be controlled by a positive-intrinsicnegative (PIN) diode across each slot. The configuration states of these three diodes are all useable that produces seven band rejection modes plus the UWB operation mode. The second antenna is configured by five PIN diodes to operate either in Cband, WLAN or Xband regions which results in three interweave modes when setting the first antenna for UWB sensing. The design is simulated by computer simulation technology (CST) v.10. S21 results shows good isolation while input reflection coefficient and realized gain results prove system’s scanning, filtering and communication capabilities. This system is new that it gathers the undelay/interweave operation in a single design and when considering its large number of operation modes it looks adequate for many cognitive radio applications.
The slides include the introduction to vehicular technology, two radio access vehicular technology DSRC & C-V2X. Also Vehicular Named Data Networking (V-NDN) along with research challenges and future research directions is presented.
The document provides an overview of GSM RF interview questions and answers. It covers topics such as the three services offered by GSM (teleservices, bearer services, and supplementary services), spectrum allocation for GSM-900 and DCS-1800, carrier frequencies and separation, ciphering and authentication algorithms, equalization, interleaving, speech coding, channel coding, frequency reuse, cell splitting, interfaces (Um, Abis, A), LAPD and LAPDm, WPS, MA, MAIO, frequency hopping types, DTX, DRX, gross data rate, Erlangs and grade of service, coverage differences between GSM900 and DCS1800, time advance, location area and location update
This document contains interview questions and answers related to GSM RF technology. It discusses topics such as the three main services offered by GSM (teleservices, bearer services, and supplementary services), spectrum allocation for GSM 900 and DCS 1800, carrier frequencies and separation, ciphering and authentication algorithms, equalization, interleaving, speech coding, channel coding, frequency reuse, cell splitting, interfaces between network elements, protocols like LAPDm, features like WPS, MA, MAIO, frequency hopping techniques, discontinuous transmission and reception, data rates, Erlangs and grade of service, path loss differences between frequency bands, timing advance, location areas and location updates, subscriber identities like IMSI and TMSI
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- Questions cover topics like the spectrum allocation for GSM900 and DCS1800, the number of carrier frequencies and their separation, ciphering and authentication algorithms, equalization techniques, interleaving, and speech coding in GSM.
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This document contains interview questions and answers related to GSM RF technology. It discusses topics like the three main services offered by GSM (teleservices, bearer services, and supplementary services), spectrum allocation for GSM 900 and DCS 1800, carrier frequencies and separation, ciphering and authentication algorithms, equalization, interleaving, speech coding, channel coding, frequency reuse, cell splitting, interfaces (Um, Abis, A), LAPD and LAPDm, WPS, MA, MAIO, frequency hopping types, HSN, DTX, DRX, GSM data rate, Erlangs and grade of service, path loss differences between GSM 900 and DCS 1800, time advance, location area
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सुप्रीम कोर्ट ने यह भी माना था कि मजिस्ट्रेट का यह कर्तव्य है कि वह सुनिश्चित करे कि अधिकारी पीएमएलए के तहत निर्धारित प्रक्रिया के साथ-साथ संवैधानिक सुरक्षा उपायों का भी उचित रूप से पालन करें।
2. 2
I. Introduction 3
II. After upgrade coverage gaps 3
Antenna azimuth plans 4
Coverage holes with twin beam antennas 4
Coverage holes with tri-beam antenna 4
Coverage holes with a twin beam surrounded by three-sector sites 4
III. PCI planning 5
Background 5
LTE air interface 5
The resource block (RB) 5
Why PCI mod 3? 6
Reference signals-RS vs. users traffic 6
The physical cell identity (PCI) 6
Intra site PCI v-shift planning 7
Problem description 7
Possible six-sector site arrangements 7
Possible nine-sector site arrangements 7
Inter site PCI v-shift planning 8
LTE-FDD case 8
Current networks situations 8
C-RAN case 8
PCI-vshift neighbors plan for tessellation deployments 8
IV. Multibeam antennas and neighbor lists limitations 9
Background 9
Neighbors’ limitations in 3GPP 9
SIB11 limitations and 3GPP releases (Idle mode) 10
SIB11 dimensioning 10
SIB11 calculations 10
SIB11 example 11
3GPP releases solution 11
Vendors proprietary solutions 11
Multicarrier vs. multibeam expansions 11
Expansion types 11
Neighbor list load calculations 11
Automatic neighbor relations (ANR) 12
Historical 12
LTE case 13
V. Conclusion 13
VI. References 13
Contents
3. 3
I. Introduction
As mobile data traffic continues to rise, there are three main ways to expand networks’
capacities: densification of sites, adding spectrum, and enhancing through technology
upgrades. While the second and third dimensions are costly, operators tend more to densify
their networks infrastructures. In mature networks, densification is achievable through a number
of techniques, such as the addition of small cells and macro sectors. While the latter is easier to
implement, it faces interference risks as a result of sector overlap.
Two single-beam vs. twin beam antenna overlap
1
Multibeam antennas add instantaneous cost-efficient capacity, eliminating the need for new
spectrum and sites building, in a minimized overlap pattern design. In this application note,
we highlight some of the major challenges and concerns with the deployment of multibeam
antennas deployment—together with recommended solutions.
II. After upgrade coverage gaps
Antenna azimuth plans
Upon upgrading from traditional to multibeam antennas, RF planners might maintain existing
panel azimuth with new beam directions (inherited panel azimuth) or preserve their beams,
bores’ plans by changing the panel azimuth (inherited beam azimuth). This is illustrated in the
figure below for a twin beam case.
For maintaining beam bores (inherited beam azimuth), a slight change in the new antenna
panel bore is made, such that one of its twin beams inherits the former single beam’s direction.
This deployment might be appealing for adding capacity with minimal disruptions.
Two single-beamed (65º) Twin beam (33º)
Traditional antenna
original azimuth
Inherited panel azimuth
changed beams azimuth
Inherited beam
azimuth adjusted panel
4. 4
Coverage holes with twin beam antennas
As a result of deploying dual-beam antennas with “inherited beam azimuth” some coverage
gaps might arise. For twin-beam antennas, rotating ALL sectors by 20 degrees solves this
problem, as shown below.
Coverage holes with tri-beam antenna
For tri-beam deployments, rotating ALL sectors by 10 degrees eliminates sectors shooting
at each other and fills up coverage gaps. This also helps in having a dominant serving cell
per area.
Coverage holes with a twin beam surrounded by three-sector sites
Again for the “inherited beam azimuth” upgrade, as shown in the left figure below, three
sectors are found shooting at each other, but no gaps (nulls) are introduced.
In the case of “inherited panel azimuth” antenna upgrade, as in the right-side figure below,
no sectors are shooting at each other but three null areas are created.
Problematic After 20-degree rotation
10o
Problematic After 10 degree rotation
5. 5
The first arrangement (inherited beam azimuth) is thus recommended, after necessary
tilts adjustments, to overcome the direct shooting bores.
III. PCI planning
Proper physical cell identities (PCI) planning, for LTE networks can result in improved
performances. With the introduction of multibeam antennas, operators have raised some PCI
planning concerns that have limited their adoption of such solutions. In this section, we explore
these concerns and propose specific workarounds.
Background
LTE air interface
To better understand these PCI planning concerns, let us remind ourselves about the structure of
LTE radio frames.
An LTE frame (10 ms) = 10 sub-frames (1 ms)
A sub-frame (1 ms) = 2 time slots (TS)
A TS (0.5 ms) = 7 symbols (normal cyclic prefix case)
The resource block (RB)
A resource block (RB) is two-dimensional: Time (1TS, x-axis) and Frequency (12 subcarriers,
y-axis) e.g. 100 RB = 20 MHz bandwidth (maximum LTE bandwidth before carrier aggregation).
Now the system needs to insert cell reference signals (RS) into fixed predetermined Time
(symbol) and Frequency (subcarrier) locations. These are marked in red in the following
diagram, depicting a system with one antenna port.
Notice that
• Time locations are at symbols 0 and 4.
• Frequency locations depend on v and v-shift.
Inherited beam azimuth swap Inherited panel azimuth swap
6. 6
V-shift is used to shift the RS frequency allocations between neighboring sectors, reducing
interference.
The v-shift = PCI mod 6 for systems with one antenna port (v+0 to v+5)
= PCI mod 3 for systems with two or four antenna ports (v+0 to v+2)
Why PCI mod 3?
Here we consider a system with two antenna ports (2x2 MIMO). The RS allocations of the first
and second antenna ports are shown in red and blue, respectively. However, each port blocks
its transmission in the other ports RS time/freq allocations (shown shaded). This gives room for
only two possible v-shift locations.
Reference signals-RS vs. users traffic
Without applying v-shifts, neighboring sectors RSes might interfere each other. With v-shift
applied, neighboring sectors RSes won’t collide any more. However, at high loads, users’
traffic can still impact the RSes, diminishing the benefits of v-shifts.
The physical cell identity (PCI)
The PCI is analogous to the UMTS PSC. The total of 504 PCI’s are grouped as follows
ID = 0 to 2, group = 0 to 167
PCI = ID + 3*group
PCIs are, thus, divided into 168 groups with three IDs in each group.
This shows 168 groups (sites) with three sectors per site (group), such that each sector has a
unique PCI mod 3. For example, the highlighted group 1 has sectors PCI = 3, 4 and 5.
7. 7
Two arrangements are further proposed for better PCI spreading, preserving mod 3 uniqueness
between sectors
The PCI ID (0 to 2) is used to derive the primary sync sequence and the PCI group is used to
derive the secondary sync sequence (0 to 167).
Intra site PCI v-shift planning
Problem description
Since normal LTE deployments use 2x2 MIMO (with two antenna ports), v-shift will always
be limited by PCI mod 3, from 0 to 2 only. This has raised concerns about complicated PCI
planning—threatening the deployment of multibeam antennas.
Possible six-sector site arrangements
As a workaround, for dual-band antennas in six-sector arrangements, the best that can be done
is to use two PCI groups per site to avoid having the same PCI mod 3 (v-shift) values between
direct adjacent sectors.
The figure below shows the possible arrangements of assigning two PCI groups to each site.
The sector color indicates the same PCI group and the numbers reflect PCI mod 3 v-shift values.
Possible nine-sector site arrangements
Similarly, the case with tri-beam antennas/nine-sector sites can be treated by assigning three
PCI groups per site. A number of arrangements are possible, as displayed below.
Problematic!! Arrangement 1 Arrangement 2
Arrangement 3 Arrangement 4 Arrangement 5
8. 8
Intersite PCI v-shift planning
Some concerns were raised also about potential conflicts between neighboring sites as well—
especially in the case of nine-sector sites.
LTE-FDD case
The LTE-FDD neighboring sites are not phase synchronized. Consequently, the OFDM symbols
0 and 4—carrying the reference signal (RS)—won’t be in sync and have much less of a
chance to collide in the neighbor site’s v-shift conflicts’ case.
In the example shown above, site 1 sector A and site 2 sector C have the same PCI v-shift
values and are direct neighbors. Since they are not phase synchronized, symbol 0 of site1A
lands on symbol 5 of site 2C. In this case, the chances of landing on the same OFDM symbol
are much less. As a result, PCI v-shift planning will be more useful for the same site’s sectors,
which are in exact phase sync.
Current networks situations
Moreover, the majority of operators won’t face neighbors, PCI v-shift conflict issue, with
multibeam antennas, for two reasons:
1. Their deployments are not following the uniform tessellation patterns.
2. Modern SON should be able to configure eNode B’s PCI values automatically.
C-RAN case
With the C-RAN concept, baseband units (BBU) are centralized as a shared pool resource for
their connected remote radio units (RRU). Not only will such a concept improve the efficiency
of hardware utilization, it also enables some of the long-anticipated LTE-A features, such as the
DL COMP. Here, C-RAN deployments will imply synchronization with neighboring RRUs, as if
they are from the same base station. Eventually, PCI v-shift planning for neighbors might be then
required, as described next.
PCI v-shift neighbors plan for tessellation deployments
The following figure proposes an example for how PCI v-shift planning can be optimized for a
three-sector tri-beam antenna site. Note that the patterns are rotated by 10 degrees avoiding
coverage gaps as explained before.
9. 9
With such a distribution, with an arrangement like pattern 4, direct neighbors are not
conflicting and there is at least one sector between each two neighbors’ sectors (dominant
server).
IV. Multibeam antennas and neighbor list limitations
Background
In UMTS WCDMA, a missing neighbor is an interferer. Neighbor relations always have to
be carefully planned. In this section, we address another major concern when it comes to
multibeam antennas: exceeding the limited possible neighbors’ definitions numbers as per the
3GPP releases. We also compare the risks imposed via expansion by multicarriers compared
to multibeam antennas.
Neighbors’ limitations in 3GPP
3GPP defines max neighbors, for a UE to handle, as follows2
• 32 intrafrequency (31, excluding serving cell)
• 32 interfrequency (for all other carriers)
• 32 inter-RAT
10. 10
Neighbor relations are sent to UE over system information block SIB11 (idle mode state),
SIB11/12 (cell_FACH, cell_PCH, URA_PCH) and over measurement control (dedicated cell_
DCH state), as shown in the figure below.
Measurement control procedures in different UE states2
SIB11 limitations and 3GPP releases (idle mode)
However, SIB11 has a max capacity of 444 bytes (3552 bits).
This size limitation results from the maximum 16 segments used to transfer a single
ASN.1-encoded SIB11. “Abstract Syntax Notation One” is a standard data communications
message description in OSI.
SIB11 dimensioning
SIB11 data load is not fixed, but is dimensioned based on the below requirements:
Neighbor relations
• Each intrafrequency neighbor, 2 bytes (16 bits)
• Each interfrequency neighbor, 6 bytes (48 bits)
• Each FEMTO neighbor, 7 bytes (56 bits)
• Each IRAT/GSM neighbor, 5 bytes (40 bits)
• Parameters
• Each neighbor QQUALMIN that deviates from serving cell, 1 byte (8 bits)
• Each neighbor QRXLEVMIN that deviates from serving cell, 1 byte (8 bits)
• Use of QOFFSET, 1 byte (8 bits)
• Header: e.g., 192 bits Ericsson, 287 bits ZTE
SIB11 calculations
Ericsson formula (source: Internet blogs)
16*intrafrequency + 48*(interfrequency – FEMTO) + 40*irat + 56*FEMTO +
8*QQUALMIN + 8* QRXLEVMIN + 8*QOFFSET1SN + 8* QOFFSET2SN + Header
ZTE formula (source: Internet blogs)
48* number of intra-neighbouring cell + 79* (number of inter-neighbouring cell - 1)
+ 75* (number of GSM neighbouring cell - 1) + Header (287)<=3330
Huawei formula (source: Internet blogs)
• Intrafrequency: serving cell: 23 bits
• Nonserving cell: 48-55 bits
• Interfrequency: per neighbour: up to 67 bits
• IRAT: per neighbour: up to 63 bits
11. 11
SIB11 example
Assuming Ericsson case without parameters’ deviation and no femtos
48*interfrequency (31) + 16*intrafrequency (32) + 40*iRat (32) + 192 = 3472 (<3552)
Assuming Ericsson with parameters’ deviation and no femtos
(48+16)*interfrequency (31) + (16+16)*intrafrequency (32) + 40*iRat (32) + 192 = 4288
(>3552)
This shows SIB11 might be unable to include all 95 neighbor relations and parameters
information.
3GPP releases solution
3GPP has introduced SIB11-bis to satisfy the full 95 neighbor relations requirements in
Release 6. Only UE’s supporting Release 6 onwards can decode SIB11-bis.
Vendors proprietary solutions
Some vendors allow definitions of more than 32 relations per category. Certain algorithms
are used to prioritize and truncate the list before sending to UEs. Others restrict the list to the
standard 32.
3
Multicarrier vs. multibeam expansions
Expansion types
When traffic overloads existing cells’ capacities, the need for expansion arises. There are
different expansion types depending on the nature of the congestion. For instance, in the UMTS
HSPA case, we have three main congestion types, as listed in the following table.
Congestion type Expansion in BBU Radio Spectrum Sector
Channel element Baseband units Yes No No No
HSDPA code More carriers (cells) No No Yes No
Multibeam antennas No Yes No Yes
Power New radio addition No Yes No No
Multibeam antennas No Yes No Yes
HSDPA code congestion can be expanded by adding more carriers (spectrum) or more sectors
(multibeam). In the case of spectrum constraints, the multibeam antennas are the best way
forward for adding sectors.
Power congestion can be solved by additional radios and redistributing the carriers among all
radios. Here, too, in case of spectrum shortages, multibeam antennas can be a good remedy.
Neighbor list load calculations
The diagram above, illustrates two expansion methods: additional carriers and multibeams.
Carriers expansion Sectors expansion
12. 12
Expanding with carriers (F1/F2/F3) will utilize both the 32 intrafrequency relations (F1→F1)
and the 32 interfrequency relations, pools (F1→F2 + F1→F3). Referring to the figure above,
each existing (F1) will get an additional x2 interfrequency relations (F2, F3). Note: we can add
only 32 more interfrequency relations to the existing 32 intrafrequency max relations.
→ That is, neighbor relations, loading for interfrequency relations is doubled compared to the
intrafrequency case. (F1→F2 + F1→F3) / 32 → 2x (F1→F1) /32
On the other hand, expanding by way of tri-beam antennas and using the same carriers
has only one pool of 32 intrafrequency relations to utilize (no additional 32 interfrequency
relations in this case). However, the neighbors, relations do not triple, as the new sectors
in-between provide sufficient isolation and not all new sectors need to be defined as neighbors.
From the below figures, immediately adjacent neighbors count (for the serving sector shown
using the red arrow) jump from 8 to 17 after deploying tri-beam antennas.
→ That is, the number of relations nearly double.
Comparing both expansion scenarios, we see that the neighbor list loading is doubled in
both cases.
Automatic neighbor relations (ANR)
Historical
In the 2G/3G era, neighbor relation definitions were mostly manual. ANR was only a function
in simulation tools. This made ANR unaware of actual users’ movements and locations, to
properly rank and prioritize.
Optimizers used to periodically check attempted handover counts. The defined relations with
the fewest handovers, over a certain span, made good candidates for deletion.
On the other hand, drive tests with UEs and attached scanners are used to identify missing
relations.
Then came some advanced features—like mobile assisted frequency allocation (MAFA). The
feature modifies neighbor lists sent to UEs, forcing them to measure and report on non-defined
neighbors for assessment.
13. 13
LTE case
When LTE was introduced, it came along with its SON concepts. So, this time, ANR resides in
eNode B. The serving cells’ eNode B can instruct its UEs to report on certain cells, PCI (similar
to the 2G MAFA concept). Such systems also have some intelligence in detecting conflicting
PCIs and reassigning proper values. More details are in a 3GPP publication.
V. Conclusion
Out of the two common antenna upgrade bore planning techniques, the “inherited beam
azimuth” is seen as less disruptive. However, a calculated uniform azimuth shift will be required
to eliminate coverage gaps in the case of multibeam antennas, tessellation deployments.
Moreover, PCI planning is crucial in optimizing LTE networks’ performance. The v-shift values
are intended to reduce intersector interferences at low-load conditions. V-shift values run from
0 to 5 (PCI mod 6) for antenna systems with one port (SISO), and from 1 to 2 (PCI mod 3) for
antenna systems of two and four ports (MIMO), since it is impossible to have unique v-shifts for
sites with six or nine sectors deploying 2x2 MIMO. A number of v-shift have been proposed
to avoid direct neighbors conflicts. The impact of conflicting PCI v-shift values, for direct
neighbors, is found to be more severe in intrasite cases than in intersite cases.
And finally, capacity expansions by multibeam antennas and multicarriers’ effects on neighbor
lists capacity loading were studied and found to be comparable.
VI. References
1
Philip Sorrells, white paper, Twin beam technology adds immediate capacity without additional antennas
2
Harri Holma and Antti Toskala, WCDMA for UMTS, 4th Edition, John Wiley and Sons
Special permission granted from John Wiley and Sons publishing. Content used in this paper with this permission
may in no way be reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic,
mechanical, photocopying, recording, scanning or otherwise.
3
http://www.telecomsource.net/showthread.php?3936-SIB11-calculation/page2
4
3GPP 36.300, sub-clause 22.3.2a