GSM is the most widely used mobile technology globally, with over 500 million users. However, it has limited data capabilities. GPRS provides a packet-switched way to access GSM networks for both interim and long-term packet data access. GPRS was defined in 1996 and began wide deployment in 2001, providing both voice and higher speed packet data access over GSM networks as an interim solution until 3G networks like UMTS are more widely available.
The document is a seminar report on Wideband Code Division Multiple Access (WCDMA) technology. It discusses the basics of WCDMA, including that it uses code division multiple access to separate users and spread signals over a wide 5MHz bandwidth. It also covers WCDMA specifications, generation, spreading principles, power control, handovers, and advantages such as service flexibility and spectrum efficiency.
Throughput calculation for LTE TDD and FDD systemsPei-Che Chang
This document discusses the calculation of throughput for LTE TDD and FDD systems. It explains that LTE systems have configurable channel bandwidth and modulation schemes, unlike fixed CDMA systems. The document then provides an example calculation of throughput for a 20 MHz bandwidth LTE FDD system using 100 resource blocks, 64QAM modulation, and 4x4 MIMO. It calculates the downlink throughput as approximately 300 Mbps and uplink as 75 Mbps after accounting for overhead. Similar calculations are shown for LTE TDD systems using different frame configurations.
Interference limits the capacity of cellular radio systems by creating bottlenecks that reduce performance. The two primary types of interference are co-channel interference, which occurs between cells using the same frequencies, and adjacent channel interference, which occurs between nearby frequency channels. Managing interference is important for cellular system design in order to minimize cross-talk and missed/blocked calls.
1) 5G NR standardization and deployments are progressing with non-standalone deployments in 2017-2019 and standalone expected in 2020.
2) 5G NR introduces improvements like flexible numerology, scalable transmission time interval, and self-contained subframes to enable low latency communications.
3) Beamforming and massive MIMO techniques along with hybrid beamforming architectures help support high bandwidth and capacity requirements of 5G networks.
N-degree ROADM Architecture Comparison: Broadcast-and-Select vs Route-and-SelectADVA
The document compares the Broadcast-and-Select and Route-and-Select architectures for N-degree ROADM nodes in 120 Gb/s DP-QPSK transmission systems. It finds that Broadcast-and-Select has slightly lower penalties than Route-and-Select for N=4 and 9 due to less passband narrowing accumulation, but Route-and-Select has better isolation and fixed insertion loss. For larger N, Route-and-Select is preferable to mitigate higher potential crosstalk. Experimental results validated the predicted penalties from combined passband and isolation degradation analysis.
On completion of the module one should be clear about the parameters required during drive test what does it mean and how much it is important.
Parameters regarding in windows like :
a) Current Channel
b) Radio parameters
c) Serving + Neighbors
Time: It is system time of computer.
Cell name: It displays the name of the sector which is serving according to the cellfile that is loaded in TEMS.
CGI : It stands for the Cell Global Identity which is unique for every sector of the site. It consists of MCC,MNC,LAC,CI.
Cell GPRS Support: Tells sector is having GPRS or not. Values are Yes or No .
Band : It tells in which Freq. Band mobile is operating e.g. GSM 900/ 1800.
BCCH ARFCN: It tells by which BCCH is the mobile station getting served.
TCH ARFCN: On which Traffic Freq. call is going on.
BSIC (Base Station Identity Code) : It is combination of Network Color Code (NCC) (0 – 7) & Base Station Color Code (BCC) (0 – 7). e.g. 62. It is decoded by mobile on every Sync. Channel Message.
Mode: It is shows in which state is mobile operating, Idle, Dedicated & Packet.
Time slot: On which time slot of current TCH call is going on. Viz. time slot no. of TRX.
This document discusses Digital Subscriber Line (DSL) technology. It defines DSL as a technology that provides digital data transmission over telephone lines. It then describes different types of DSL technologies including ADSL, VDSL, and SDSL. It also discusses how DSL works by using different frequencies to transmit voice and data simultaneously over the same telephone line. Finally, it provides an overview of how DSL connectivity is established from the customer premises to the DSL access multiplexer (DSLAM) and further into the telephone company's network.
Overview Of Gsm Cellular Network & OperationsDeepak Sharma
The document provides an overview of the GSM cellular network and its operations. It describes the main components including the mobile switching center (MSC), home location register (HLR), visitor location register (VLR), and authentication center (AUC). It also discusses the mobile handset, radio interface, network architecture, and how capacity is increased through frequency reuse, cell splitting, and sectoring.
The document is a seminar report on Wideband Code Division Multiple Access (WCDMA) technology. It discusses the basics of WCDMA, including that it uses code division multiple access to separate users and spread signals over a wide 5MHz bandwidth. It also covers WCDMA specifications, generation, spreading principles, power control, handovers, and advantages such as service flexibility and spectrum efficiency.
Throughput calculation for LTE TDD and FDD systemsPei-Che Chang
This document discusses the calculation of throughput for LTE TDD and FDD systems. It explains that LTE systems have configurable channel bandwidth and modulation schemes, unlike fixed CDMA systems. The document then provides an example calculation of throughput for a 20 MHz bandwidth LTE FDD system using 100 resource blocks, 64QAM modulation, and 4x4 MIMO. It calculates the downlink throughput as approximately 300 Mbps and uplink as 75 Mbps after accounting for overhead. Similar calculations are shown for LTE TDD systems using different frame configurations.
Interference limits the capacity of cellular radio systems by creating bottlenecks that reduce performance. The two primary types of interference are co-channel interference, which occurs between cells using the same frequencies, and adjacent channel interference, which occurs between nearby frequency channels. Managing interference is important for cellular system design in order to minimize cross-talk and missed/blocked calls.
1) 5G NR standardization and deployments are progressing with non-standalone deployments in 2017-2019 and standalone expected in 2020.
2) 5G NR introduces improvements like flexible numerology, scalable transmission time interval, and self-contained subframes to enable low latency communications.
3) Beamforming and massive MIMO techniques along with hybrid beamforming architectures help support high bandwidth and capacity requirements of 5G networks.
N-degree ROADM Architecture Comparison: Broadcast-and-Select vs Route-and-SelectADVA
The document compares the Broadcast-and-Select and Route-and-Select architectures for N-degree ROADM nodes in 120 Gb/s DP-QPSK transmission systems. It finds that Broadcast-and-Select has slightly lower penalties than Route-and-Select for N=4 and 9 due to less passband narrowing accumulation, but Route-and-Select has better isolation and fixed insertion loss. For larger N, Route-and-Select is preferable to mitigate higher potential crosstalk. Experimental results validated the predicted penalties from combined passband and isolation degradation analysis.
On completion of the module one should be clear about the parameters required during drive test what does it mean and how much it is important.
Parameters regarding in windows like :
a) Current Channel
b) Radio parameters
c) Serving + Neighbors
Time: It is system time of computer.
Cell name: It displays the name of the sector which is serving according to the cellfile that is loaded in TEMS.
CGI : It stands for the Cell Global Identity which is unique for every sector of the site. It consists of MCC,MNC,LAC,CI.
Cell GPRS Support: Tells sector is having GPRS or not. Values are Yes or No .
Band : It tells in which Freq. Band mobile is operating e.g. GSM 900/ 1800.
BCCH ARFCN: It tells by which BCCH is the mobile station getting served.
TCH ARFCN: On which Traffic Freq. call is going on.
BSIC (Base Station Identity Code) : It is combination of Network Color Code (NCC) (0 – 7) & Base Station Color Code (BCC) (0 – 7). e.g. 62. It is decoded by mobile on every Sync. Channel Message.
Mode: It is shows in which state is mobile operating, Idle, Dedicated & Packet.
Time slot: On which time slot of current TCH call is going on. Viz. time slot no. of TRX.
This document discusses Digital Subscriber Line (DSL) technology. It defines DSL as a technology that provides digital data transmission over telephone lines. It then describes different types of DSL technologies including ADSL, VDSL, and SDSL. It also discusses how DSL works by using different frequencies to transmit voice and data simultaneously over the same telephone line. Finally, it provides an overview of how DSL connectivity is established from the customer premises to the DSL access multiplexer (DSLAM) and further into the telephone company's network.
Overview Of Gsm Cellular Network & OperationsDeepak Sharma
The document provides an overview of the GSM cellular network and its operations. It describes the main components including the mobile switching center (MSC), home location register (HLR), visitor location register (VLR), and authentication center (AUC). It also discusses the mobile handset, radio interface, network architecture, and how capacity is increased through frequency reuse, cell splitting, and sectoring.
. Overview
2. Handover Causes & Priorities
3. Threshold Comparison Process
4. Target Cell Evaluation Process
5. Handover Algorithms
Power Budget (PBGT)
Level & Quality (RXLEV & RXQUAL)
Umbrella (& Combined Umbrella/PBGT)
MS Speed (FMMS & MS_SPEED_DETECTION)
6. Imperative Handovers
Distance
Rapid Field Drop (RFD) & Enhanced Rapid Field Drop (ERFD)
7. Handover Timers
Call continuity - to ensure a call can be maintained as a MS moves geographical location from the coverage area of one cell to another
Call quality - to ensure that if an MS moves into a poor quality/coverage area the call can be moved from the serving cell to a neighbouring cell (with better quality) without dropping the call
Traffic Reasons - to ensure that the traffic within the network is optimally
distributed between the different layers/bands of a network
If 2 or more handover (PC) criteria are satisfied simultaneously the following priority list
is used in determining which process is performed;
. Uplink and downlink Interference
2. Uplink quality
3. Downlink quality
4. Uplink level
5. Downlink level
6. Distance
7. Enhanced (RFD)
8. Rapid Field Drop (RFD)
9. Slow moving MS
10. Better cell i.e. Periodic check (Power Budget HO or Umbrella HO)
11. PC: Lower quality/level thresholds (UL/DL)
12. PC: Upper quality/level thresholds (UL/DL)
Long Term Evolution (LTE) is a 4G mobile communication standard that aims to provide faster data speeds and network capacity. LTE targets peak download speeds of 100 Mbps for 20 MHz of spectrum and aims to reduce latency to less than 5 ms. It utilizes OFDM and MIMO technologies to achieve these goals. LTE has a simplified all-IP based architecture compared to 3G and supports spectrum bandwidths from 1.25-20 MHz. As of 2010, over 60 mobile operators had committed to deploying LTE networks in over 30 countries. LTE is expected to become the dominant next-generation mobile broadband technology globally.
This document describes the ZXSDR BS8700 software defined radio base station, which consists of a BBU and series of RRUs. Key features include:
- Integrating GSM and UMTS radio networks into a single network to reduce costs by using a single base station that can be flexibly configured for GSM or UMTS via software.
- Adopting a distributed architecture with a baseband unit and remote radio units connected via optical fiber for increased flexibility and capacity.
- Supporting both single-mode GSM, UMTS, or dual-mode GSM/UMTS configurations through software settings to provide converged 2G and 3G network functionality.
This document provides an overview of telecom concepts and GSM technology. It discusses early analog cellular systems, the development of GSM standards to address limitations in analog networks, and key aspects of GSM including frequency reuse, handovers, and network architecture. The document also covers cellular concepts like frequency bands, modulation techniques, and components of the mobile station and subscriber identity module.
Ericsson 2 g ran optimization complete trainingsekit123
This document provides an overview of Ericsson 2G RAN optimization training. It outlines the purpose of the training, which is to give an overview of Ericsson hardware capabilities and limitations and provide an in-depth introduction to optimization processes and features. The document summarizes key hardware such as BSCs, RBSs, TRUs, and CDUs as well as concepts like channel allocation profiles and quality measurement. It also lists common Ericsson optimization tools.
Digital Mobile Network Evolution - from GSM to 5G3G4G
A network centric view of the evolution of digital cellular mobile communications systems; from 2G GSM, through 3G UMTS, 4G LTE to 5G.
Lecture delivered by Prof. Andy Sutton at The IET Digital Communications event on 24 Oct 2019 at University of Suffolk, Ipswich, United Kingdom
***** SHARED WITH PERMISSION *****
CE resources are a type of hardware resource in NodeBs that measure channel demodulation capabilities. The number of CEs supported by a NodeB determines how many users and what types of services it can support. CEs are managed jointly by the RNC and NodeB to ensure resources are used properly. The number of CEs consumed depends on the type of service and can be calculated based on mappings provided in the document.
This document provides an overview of 5G technology and its advantages over 4G LTE. It discusses the different 5G use cases like enhanced mobile broadband, massive IoT, and critical communications. It describes the evolution of radio technology including the use of new spectrum bands and massive MIMO. It also covers network architecture aspects such as centralized RAN deployments and functional splits between centralized and distributed units. The document is intended as a tutorial for IP engineers to understand 5G network capabilities and requirements.
5th generation mobile networks or 5th generation wireless systems is abbreviated as 5G, and proposed next telecommunications standards beyond the current 4G/IMT-Advanced standards. 5G planning aims at higher capacity than current 4G, allowing a higher density of mobile broadband users, and supporting device-to-device, ultra reliable, and massive machine communications. Its research and development also aims at lower latency than 4G equipment and lower battery consumption, for better implementation of the Internet of things.
The document discusses GSM network optimization techniques including adjusting parameters for cell selection, power control, and handover control to improve coverage, interference, and handover behavior. It describes the optimization process including initial, primary, and maintenance phases. Key parameters and techniques discussed include enabling features like discontinuous transmission, frequency hopping, and power control as well as adjusting neighbor cell lists, antenna configuration, and frequencies. Drive testing is used to identify problems, verify solutions, and ensure quality.
The document provides an overview of GSM protocols:
- It describes the 7 layers of the OSI model and how they relate to network support layers (physical and data link layers) and user support layers (session, presentation, and application layers).
- It explains key GSM protocol layers including the physical layer, data link layer, and signaling layers used for call setup and termination between mobile devices and the core network.
- It also discusses common protocols used in telephone networks like ISDN, SS7, and how protocols like SCCP, TCAP, MAP, and INAP are used to support services like roaming and calling card transactions.
This document provides an overview of DWDM transmission systems. It defines DWDM and describes how it uses multiple wavelengths of light to transmit parallel data. It discusses how DWDM helps overcome bandwidth limitations and enables transmission over long distances using technologies like EDFAs. The document outlines DWDM network structures, key components, protection schemes, and evolution over time to support higher capacities and network flexibility.
The document provides an overview of Long Term Evolution (LTE) technology. It discusses that LTE is the next generation mobile network standard that uses an all-IP flat network architecture. LTE networks employ OFDMA for the downlink and SC-FDMA for the uplink. Key performance targets of LTE include peak data rates of over 100 Mbps downlink and 50 Mbps uplink, low latency, and improved spectrum efficiency. The document also outlines the LTE network architecture including components like the eNodeB, MME, SGW, and PGW.
This document describes the ZXSDR BS8700 software defined radio base station, which consists of a baseband unit (BBU) and remote radio units (RRUs). The BS8700 can be flexibly configured through software alone to function as a GSM or UMTS system, integrating 2G and 3G radio networks on a single platform. It introduces key product highlights, functionalities, system architecture including hardware and software components, technical specifications, operation and maintenance features. Configuration principles are provided for GSM single-mode, UMTS single-mode, and GSM/UMTS dual-mode network deployments.
This document provides an overview of 4G LTE technology. It discusses key LTE concepts such as OFDM and MIMO used in the downlink and uplink, as well as requirements for IMT-Advanced systems. It describes the 3GPP releases that specified LTE and LTE-Advanced standards and components of the LTE network architecture including the E-UTRAN, EPC, and interfaces between nodes. The document also provides explanations of OFDM, MIMO, SC-FDMA, and the LTE physical layer frame structure and resource grid. Special features introduced in LTE-Advanced like carrier aggregation and relaying are also summarized.
The document describes power control configuration and mechanisms in UMTS networks. It discusses power control models and parameters. Open-loop power control sets initial uplink and downlink transmit power levels. For uplink on PRACH, the UE calculates initial preamble power based on measured CPICH_RSCP and parameters in system information blocks including CPICH transmit power, UL interference level, and a constant value. Power is then ramped for preamble retransmissions and set for the message part.
1) DWDM combines multiple optical signals so that they can be amplified and transmitted over a single fiber, increasing network capacity.
2) Basic DWDM system components include terminal multiplexers and demultiplexers, line repeaters, and optical terminals. Optical add-drop multiplexers allow removal or insertion of wavelengths along the span.
3) Proper link budgeting is required to ensure optical power levels remain above minimum thresholds to maintain signal quality as light propagates long distances through fiber. Regular monitoring and troubleshooting helps ensure transmission quality parameters are met.
In this paper, we discussed about LTE system throughput calculation for both TDD and FDD system.
3GPP LTE technology support both TDD and FDD multiplexing. The paper describes all the factors which affect the throughput like Bandwidth, Modulation, UE category and mulplexing. It also describes how we get throughput 300Mbps in DL and 75Mbps in UL and what are assumptions taken to calculate the same.
Paper describes the steps and formulae to calculate the throughput for FDD system for TDD Config 1 and Config 2.
The throughput calculations shown in this paper is theoretical and limited by the assumptions taken to calculate for calculations
COMPUTEX TAIPEI 2013 - Smart Living Industry Forum
Topic: Adding Intelligence to Grids - Siemens Smart Grid Solutions for a Sustainable Future
Speaker:Erdal Elver
President and Chief Executive Officer, Siemens Ltd., Taiwan
Mobile apps are increasingly incorporating artificial intelligence capabilities to enhance user experience. Developers can leverage AI and machine learning technologies to gain insights from user data and customize apps for individual preferences and behaviors. This allows apps to become more intuitive, personalized and useful for consumers over time through ongoing analysis of how people interact with their mobile devices.
. Overview
2. Handover Causes & Priorities
3. Threshold Comparison Process
4. Target Cell Evaluation Process
5. Handover Algorithms
Power Budget (PBGT)
Level & Quality (RXLEV & RXQUAL)
Umbrella (& Combined Umbrella/PBGT)
MS Speed (FMMS & MS_SPEED_DETECTION)
6. Imperative Handovers
Distance
Rapid Field Drop (RFD) & Enhanced Rapid Field Drop (ERFD)
7. Handover Timers
Call continuity - to ensure a call can be maintained as a MS moves geographical location from the coverage area of one cell to another
Call quality - to ensure that if an MS moves into a poor quality/coverage area the call can be moved from the serving cell to a neighbouring cell (with better quality) without dropping the call
Traffic Reasons - to ensure that the traffic within the network is optimally
distributed between the different layers/bands of a network
If 2 or more handover (PC) criteria are satisfied simultaneously the following priority list
is used in determining which process is performed;
. Uplink and downlink Interference
2. Uplink quality
3. Downlink quality
4. Uplink level
5. Downlink level
6. Distance
7. Enhanced (RFD)
8. Rapid Field Drop (RFD)
9. Slow moving MS
10. Better cell i.e. Periodic check (Power Budget HO or Umbrella HO)
11. PC: Lower quality/level thresholds (UL/DL)
12. PC: Upper quality/level thresholds (UL/DL)
Long Term Evolution (LTE) is a 4G mobile communication standard that aims to provide faster data speeds and network capacity. LTE targets peak download speeds of 100 Mbps for 20 MHz of spectrum and aims to reduce latency to less than 5 ms. It utilizes OFDM and MIMO technologies to achieve these goals. LTE has a simplified all-IP based architecture compared to 3G and supports spectrum bandwidths from 1.25-20 MHz. As of 2010, over 60 mobile operators had committed to deploying LTE networks in over 30 countries. LTE is expected to become the dominant next-generation mobile broadband technology globally.
This document describes the ZXSDR BS8700 software defined radio base station, which consists of a BBU and series of RRUs. Key features include:
- Integrating GSM and UMTS radio networks into a single network to reduce costs by using a single base station that can be flexibly configured for GSM or UMTS via software.
- Adopting a distributed architecture with a baseband unit and remote radio units connected via optical fiber for increased flexibility and capacity.
- Supporting both single-mode GSM, UMTS, or dual-mode GSM/UMTS configurations through software settings to provide converged 2G and 3G network functionality.
This document provides an overview of telecom concepts and GSM technology. It discusses early analog cellular systems, the development of GSM standards to address limitations in analog networks, and key aspects of GSM including frequency reuse, handovers, and network architecture. The document also covers cellular concepts like frequency bands, modulation techniques, and components of the mobile station and subscriber identity module.
Ericsson 2 g ran optimization complete trainingsekit123
This document provides an overview of Ericsson 2G RAN optimization training. It outlines the purpose of the training, which is to give an overview of Ericsson hardware capabilities and limitations and provide an in-depth introduction to optimization processes and features. The document summarizes key hardware such as BSCs, RBSs, TRUs, and CDUs as well as concepts like channel allocation profiles and quality measurement. It also lists common Ericsson optimization tools.
Digital Mobile Network Evolution - from GSM to 5G3G4G
A network centric view of the evolution of digital cellular mobile communications systems; from 2G GSM, through 3G UMTS, 4G LTE to 5G.
Lecture delivered by Prof. Andy Sutton at The IET Digital Communications event on 24 Oct 2019 at University of Suffolk, Ipswich, United Kingdom
***** SHARED WITH PERMISSION *****
CE resources are a type of hardware resource in NodeBs that measure channel demodulation capabilities. The number of CEs supported by a NodeB determines how many users and what types of services it can support. CEs are managed jointly by the RNC and NodeB to ensure resources are used properly. The number of CEs consumed depends on the type of service and can be calculated based on mappings provided in the document.
This document provides an overview of 5G technology and its advantages over 4G LTE. It discusses the different 5G use cases like enhanced mobile broadband, massive IoT, and critical communications. It describes the evolution of radio technology including the use of new spectrum bands and massive MIMO. It also covers network architecture aspects such as centralized RAN deployments and functional splits between centralized and distributed units. The document is intended as a tutorial for IP engineers to understand 5G network capabilities and requirements.
5th generation mobile networks or 5th generation wireless systems is abbreviated as 5G, and proposed next telecommunications standards beyond the current 4G/IMT-Advanced standards. 5G planning aims at higher capacity than current 4G, allowing a higher density of mobile broadband users, and supporting device-to-device, ultra reliable, and massive machine communications. Its research and development also aims at lower latency than 4G equipment and lower battery consumption, for better implementation of the Internet of things.
The document discusses GSM network optimization techniques including adjusting parameters for cell selection, power control, and handover control to improve coverage, interference, and handover behavior. It describes the optimization process including initial, primary, and maintenance phases. Key parameters and techniques discussed include enabling features like discontinuous transmission, frequency hopping, and power control as well as adjusting neighbor cell lists, antenna configuration, and frequencies. Drive testing is used to identify problems, verify solutions, and ensure quality.
The document provides an overview of GSM protocols:
- It describes the 7 layers of the OSI model and how they relate to network support layers (physical and data link layers) and user support layers (session, presentation, and application layers).
- It explains key GSM protocol layers including the physical layer, data link layer, and signaling layers used for call setup and termination between mobile devices and the core network.
- It also discusses common protocols used in telephone networks like ISDN, SS7, and how protocols like SCCP, TCAP, MAP, and INAP are used to support services like roaming and calling card transactions.
This document provides an overview of DWDM transmission systems. It defines DWDM and describes how it uses multiple wavelengths of light to transmit parallel data. It discusses how DWDM helps overcome bandwidth limitations and enables transmission over long distances using technologies like EDFAs. The document outlines DWDM network structures, key components, protection schemes, and evolution over time to support higher capacities and network flexibility.
The document provides an overview of Long Term Evolution (LTE) technology. It discusses that LTE is the next generation mobile network standard that uses an all-IP flat network architecture. LTE networks employ OFDMA for the downlink and SC-FDMA for the uplink. Key performance targets of LTE include peak data rates of over 100 Mbps downlink and 50 Mbps uplink, low latency, and improved spectrum efficiency. The document also outlines the LTE network architecture including components like the eNodeB, MME, SGW, and PGW.
This document describes the ZXSDR BS8700 software defined radio base station, which consists of a baseband unit (BBU) and remote radio units (RRUs). The BS8700 can be flexibly configured through software alone to function as a GSM or UMTS system, integrating 2G and 3G radio networks on a single platform. It introduces key product highlights, functionalities, system architecture including hardware and software components, technical specifications, operation and maintenance features. Configuration principles are provided for GSM single-mode, UMTS single-mode, and GSM/UMTS dual-mode network deployments.
This document provides an overview of 4G LTE technology. It discusses key LTE concepts such as OFDM and MIMO used in the downlink and uplink, as well as requirements for IMT-Advanced systems. It describes the 3GPP releases that specified LTE and LTE-Advanced standards and components of the LTE network architecture including the E-UTRAN, EPC, and interfaces between nodes. The document also provides explanations of OFDM, MIMO, SC-FDMA, and the LTE physical layer frame structure and resource grid. Special features introduced in LTE-Advanced like carrier aggregation and relaying are also summarized.
The document describes power control configuration and mechanisms in UMTS networks. It discusses power control models and parameters. Open-loop power control sets initial uplink and downlink transmit power levels. For uplink on PRACH, the UE calculates initial preamble power based on measured CPICH_RSCP and parameters in system information blocks including CPICH transmit power, UL interference level, and a constant value. Power is then ramped for preamble retransmissions and set for the message part.
1) DWDM combines multiple optical signals so that they can be amplified and transmitted over a single fiber, increasing network capacity.
2) Basic DWDM system components include terminal multiplexers and demultiplexers, line repeaters, and optical terminals. Optical add-drop multiplexers allow removal or insertion of wavelengths along the span.
3) Proper link budgeting is required to ensure optical power levels remain above minimum thresholds to maintain signal quality as light propagates long distances through fiber. Regular monitoring and troubleshooting helps ensure transmission quality parameters are met.
In this paper, we discussed about LTE system throughput calculation for both TDD and FDD system.
3GPP LTE technology support both TDD and FDD multiplexing. The paper describes all the factors which affect the throughput like Bandwidth, Modulation, UE category and mulplexing. It also describes how we get throughput 300Mbps in DL and 75Mbps in UL and what are assumptions taken to calculate the same.
Paper describes the steps and formulae to calculate the throughput for FDD system for TDD Config 1 and Config 2.
The throughput calculations shown in this paper is theoretical and limited by the assumptions taken to calculate for calculations
COMPUTEX TAIPEI 2013 - Smart Living Industry Forum
Topic: Adding Intelligence to Grids - Siemens Smart Grid Solutions for a Sustainable Future
Speaker:Erdal Elver
President and Chief Executive Officer, Siemens Ltd., Taiwan
Mobile apps are increasingly incorporating artificial intelligence capabilities to enhance user experience. Developers can leverage AI and machine learning technologies to gain insights from user data and customize apps for individual preferences and behaviors. This allows apps to become more intuitive, personalized and useful for consumers over time through ongoing analysis of how people interact with their mobile devices.
Waves of Innovation: Using Google Wave in the ESL ClassroomDavid Bartsch
This document provides an overview of using Google Wave in ESL classrooms. It begins with some assumptions about the audience and their interest in and comfort with technology. It then describes what Wave is and its key features, such as collaborative editing, playback, and gadgets. Various uses of Wave for language learning are proposed, both in and out of the classroom. The theoretical justification for using Wave and CALL is discussed based on social constructivism. Both strengths and weaknesses of Wave are presented. Predictions are made about Wave's potential to transform language learning.
This document provides an overview of broadband and wireless communication technologies. It begins with definitions of broadband and a brief history of the development of the Internet. It then discusses GSM technology including its definition, history, and architecture. It also covers antenna types including omni-directional and directional antennas. The document aims to introduce concepts related to broadband networks and wireless communications.
Neural networks are mathematical models inspired by biological neural networks. They are useful for pattern recognition and data classification through a learning process of adjusting synaptic connections between neurons. A neural network maps input nodes to output nodes through an arbitrary number of hidden nodes. It is trained by presenting examples to adjust weights using methods like backpropagation to minimize error between actual and predicted outputs. Neural networks have advantages like noise tolerance and not requiring assumptions about data distributions. They have applications in finance, marketing, and other fields, though designing optimal network topology can be challenging.
The document discusses IP addressing and routing in LTE networks. It covers:
- OSI layers used in LTE including physical, MAC, RLC, and PDCP layers
- IP addressing schemes including IPv4 addressing, subnetting, and network/broadcast addresses
- IP routing configuration in BSCs, RNCs, and between network nodes
- Interface IP allocation and configuration of BTS, NodeB, and OAM addresses
This document provides an overview of Google Wave terminology and features. It defines the key terms "wave", "wavelet", and "blip" which refer to different levels of threaded conversations. It also describes extensions like gadgets and robots that can be added to waves. Finally it demonstrates how to perform common tasks in waves like adding contacts, inserting pictures, videos, documents and more.
This document discusses Google Wave and provides an overview of its key features and capabilities. It describes Wave as a communications and collaboration platform that allows information to be shared in real-time waves. It outlines some of Wave's interface elements and how extensions can be built through gadgets and robots to enhance its functionality. Examples of potential enterprise uses through business process modeling and productivity improvements are also mentioned.
What is Intelligent agent, Abstract Intelligent Agents, Autonomous Intelligent Agents, Classes of intelligent agents, Application of an intelligent agent, Capabilities of an intelligent agent, Limitations of an intelligent agent.
This document discusses using artificial neural networks for image compression and decompression. It begins with an introduction explaining the need for image compression due to large file sizes. It then describes biologically inspired neurons and artificial neural networks. The document outlines the backpropagation algorithm, various compression techniques, and how neural networks were implemented in MATLAB and on an FPGA board for this project. It discusses the advantages of neural networks for this application, some disadvantages, and examples of applications. In conclusion, it states that the design was successfully implemented on an FPGA board and input and output values were similar, showing the neural network approach works for image compression.
IP spoofing involves falsifying the source IP address of packets sent over the Internet in order to gain an illegitimate advantage or perform malicious acts. There are several types of spoofing, but IP spoofing is used to impersonate another computer in order to access restricted networks or obtain sensitive information. Attackers use IP spoofing in denial of service attacks by flooding victims with spoofed packets to overwhelm their resources. Defenses against IP spoofing include filtering packets at routers to validate source addresses and using cryptographic network protocols to authenticate communications.
This document provides an introduction to using Actix Analyzer software for analyzing GSM network performance. It covers loading and viewing drive test and other radio network data, performing queries and filters on the data, configuring cell sites and networks, and generating reports. Key features discussed include mapping cells and drive test data, binning and aggregating data, exploring data on charts and tables, and using preconfigured applications and reports for common analysis tasks.
Brief description about the various E-Payment Systems :
E-Cash, E-Cheques,E-Wallets, Credit and Debit Cards transaction systems, Electronic Clearing Systems...
Their various drawbacks and advantages and disadvantages.
A SAN (Storage Area Network) is a network designed to transfer data from servers to storage targets as an alternative to directly attached storage. The document defines SAN architecture, which accesses storage at the block level and provides high performance, shared storage with good management tools. It discusses various SAN technologies like Fiber Channel and IP-based solutions. SANs connect storage subsystems, while NAS uses a general network to connect file-based storage. The document also covers SAN topologies, virtualization, protocols, advantages and disadvantages.
The document discusses key concepts in GSM cellular networks including:
1. An overview of GSM including its definition, phases, specifications, system architecture, network areas, and advantages over analog systems.
2. Cell planning principles such as types of cells, the planning process, and cell clusters.
3. Frequency reuse which allows frequencies to be reused in different cells to improve capacity, with an example shown.
A brief study on Storage Area Network (SAN), SAN architecture & its importance. It focuses on the techniques and the technologies that have evolved around SAN & its Security.
This document discusses packet sniffing and methods for detecting packet sniffers. It defines packet sniffing as monitoring all network packets and describes common packet sniffer tools like tcpdump. It explains that packet sniffers can be used for both legitimate and malicious purposes, such as password theft or network mapping. The document outlines two key methods for detecting packet sniffers - MAC detection and DNS detection. MAC detection works by sending packets with invalid MAC addresses and checking if any hosts respond in promiscuous mode. DNS detection exploits the behavior of sniffers performing DNS lookups on spoofed source IP addresses. Both methods were found to accurately detect the presence of packet sniffers on a network.
This document provides an overview of the history and evolution of mobile radio networks from 1G to 3G. It discusses the development of early cellular networks using analog technologies in the 1970s-1980s and the transition to digital 2G networks in the 1990s using technologies like GSM, CDMA, and TDMA. It then introduces 3G networks, which aimed to support higher data rates, multimedia services, and greater network capacity through more spectrally efficient wireless technologies like W-CDMA and CDMA2000. The document outlines the international standardization efforts around 3G and different radio access technologies being developed and deployed globally.
Introduction To Cellular And Wireless NetworksYoram Orzach
This document provides an overview of cellular and wireless networks. It discusses the history and evolution of 1G to 4G cellular networks, including the development of technologies like GSM, CDMA, UMTS, HSPA and LTE. It also covers the basics of wireless local area networks (WiFi) and describes the IEEE 802.11 standards including 802.11b, 802.11g and 802.11n. Finally, it discusses future trends in both cellular and wireless networks.
The document is a tutorial on 3G technologies that provides an overview of:
1) The history and evolution of mobile radio technologies from 1G analog systems to 2G digital systems like GSM and CDMA.
2) Evolving network architectures including the 3GPP and 3GPP2 evolution paths and potential for convergence using softswitches and VoIP.
3) International standards for 3G radio including W-CDMA, CDMA2000, and TD-SCDMA as well as the vision for IMT-2000.
Overview of current communications systemsMohd Arif
The document provides an overview of current communications systems, including the growth and evolution of cellular technologies from 1G to 3G. It summarizes the key 2G technologies like GSM, CDMA, and TDMA, as well as 2.5G and 3G standards that support higher data rates. It also discusses emerging broadband wireless services for local and personal area networks using technologies like Wi-Fi, HIPERLAN, and Bluetooth.
Seminar: Wireless Technology at Elektro UI.May05Djadja Sardjana
This document discusses the history and principles of wireless technology, including GSM and CDMA standards. It then focuses on introducing EDGE technology, which allows higher data transmission rates over existing GSM networks. The presentation agenda indicates it will cover wireless history, principles of wireless standards like GSM and CDMA, emerging 3G technologies, and finally provide an introduction to EDGE technology and its capabilities.
This document provides an overview of 3G mobile radio technology. It begins with a brief history of cellular wireless standards from 1G to 2G, including AMPS, TDMA, CDMA, GSM and their evolution. It then discusses evolving network architectures, focusing on the migration from GSM and ANSI-41 networks to all-IP networks. The document also outlines evolving services, applications and business models for 3G. Key topics covered include 3G standards like UMTS, CDMA2000 and TD-SCDMA, as well as spectrum bands and the challenges of global roaming.
The document discusses the evolution of wireless networks from 1G to 4G. It describes the key technologies including 1G analog cellular systems, 2G digital systems, 2.5G technologies like GPRS and EDGE, 3G standards like UMTS, CDMA2000, and W-CDMA. 3G services offered higher data rates and quality of service but faced challenges around high costs and lack of coverage. 4G is still in development and aims to offer speeds 50 times faster than 3G with seamless connectivity anywhere. Key 3G standards that emerged include CDMA2000 1X, EV-DO, and UMTS/W-CDMA, with W-CDMA providing larger bandwidth and capacity with lower
The document discusses the Global System for Mobile (GSM) communications, including an overview of GSM concepts, system architecture, identities and channels used, the radio link, mobility and call management, and radio resource management. It provides background on the development of GSM standards and specifications. The document also covers topics like GSM network structures, frequency bands, channel access techniques, and mobility functions like timing advance.
The document discusses some limitations and difficulties of wireless technologies. It notes that while wireless is convenient, there are political and technical challenges that inhibit the technologies. Specifically, it points out a lack of industry standards and limitations of devices, such as small screens that can only display a few lines of text and use of WML instead of HTML on most mobile browsers.
Wireless communication and its standardsM.k. Praveen
The document discusses wireless communication standards and cellular technology. It provides an agenda covering topics like wireless communication, cellular technology, standards evolution, modulation and multiplexing techniques, and cellular standards like GSM and CDMA. It also discusses frequency division multiple access (FDMA), time division multiple access (TDMA), code division multiple access (CDMA), and the differences between the 900MHz and 1800MHz frequency bands used in cellular networks.
Cellular networks have evolved from 0G to 5G over several generations of technology. 1G networks in the early 1980s used analog transmission for primarily voice calls. 2G digital networks in the late 1980s enabled services like text messages. 3G networks in the 2000s supported broadband multimedia with speeds up to 2Mbps. 4G networks since 2010 provide faster "anytime, anywhere" services using IP. Research into 5G beyond 2020 aims for speeds over 10Gbps and connectivity of billions of devices. Each generation brought major improvements in speed and capabilities.
The document summarizes the history of mobile communication from 1G to 4G technologies. It discusses the evolution from early analog 1G systems developed in the 1970s-80s to 2G digital GSM networks in the 1980s-90s capable of voice and limited data. 3G systems launched in the late 1990s provided improved voice quality and higher speed data up to 2Mbps. Emerging 4G technologies are expected to offer data rates from 20-100Mbps. The document also provides an overview of the fundamental principles of cellular networks and discusses GSM as the most widely used 2G digital standard globally.
The document discusses the transition from GSM networks to 3G networks using UMTS (Universal Mobile Telecommunications System) and W-CDMA (Wideband Code Division Multiple Access) technology. It provides an overview of the 3 steps to transition: from current GSM networks to 2.5G networks with GPRS added, to 3G networks using UMTS and W-CDMA. Key aspects of W-CDMA such as its frequencies, multiple access techniques, and spreading codes used are summarized.
1) Different generations of cellular networks include 1G, 2G, 2.5G, 3G, and 4G. 1G networks used analog signals and included early systems like AMPS. 2G networks introduced digital signaling and standards like GSM and CDMA. 2.5G networks improved data capabilities of 2G. 3G enabled high-speed data and services beyond voice calls. 4G provides high-speed data and bandwidth on demand.
2) AMPS was the first 1G cellular network, operating in the 1980s-1990s in North America. It used analog FM technology with channel spacing of 30KHz. Key components included mobile stations, base stations, and mobile switching offices
This document discusses various wireless networks including WiMAX, cellular networks, and satellite networks. It describes WiMAX services and standards, the evolution of cellular networks from 1G to 4G, and key aspects of satellite network operations including orbit types, footprints, and frequency bands. Specifically, it outlines the characteristics of GEO, MEO, and LEO satellite orbits and provides examples for each type. The document provides a technical overview of the technologies, standards, and applications of several major wireless networking approaches.
Intends to discuss about new data centric environment challenges due tsunami data traffic in mobile broadband and how industry is being prepared to address all of these changes.
This document provides an overview of cellular communications technologies, including GSM and GPRS. It discusses the history from early analogue cellular systems to the development of GSM as the first digital standard. Key topics covered include the radio environment and network subsystems of GSM, as well as signalling and transmission. The document also briefly outlines the evolution to 3G systems such as UMTS.
3G cellular networks aimed to provide higher bandwidth and data rates, global roaming, and support for multimedia services. The ITU defined the IMT-2000 standard to enable these capabilities. Major 3G technologies included W-CDMA, CDMA2000, and UWC-136. Early 3G networks rolled out starting in 2001, with the Japanese and Koreans among the first to offer services meeting IMT-2000 specifications. Key technologies like higher bandwidths, packet switching, coherent modulation, smart antennas, and interference management helped 3G networks provide improved performance over 2G networks.
Cellular networks have evolved from 1G to 4G over several decades, with increasing data rates at each generation:
1) 1G networks in the 1980s provided analog cellular service with data rates under 1 Kbps.
2) 2G digital networks in the 1990s enabled data rates from 9.6 Kbps to 10s of Kbps.
3) 3G networks from the 2000s provided multimedia broadband connectivity from 144 Kbps to 2 Mbps.
4) 4G and beyond aims to deliver data rates over 20 Mbps for next-generation wireless broadband access.
Mobile wireless evolution began with analog 1G networks in the 1980s using Frequency Division Multiple Access (FDMA). 1G systems used analog signals and large frequency bandwidths. Later, 2G digital networks in the 1990s provided more efficient use of spectrum through digital modulation, speech coding, and Time Division Multiple Access (TDMA). Code Division Multiple Access (CDMA) was then introduced in the mid-1990s and supported many more users through spread spectrum technology.
1. Course 335
GSM 2.5G Migration:
GSM 2.5G Migration:
General Packet Radio Service GPRS
General Packet Radio Service GPRS
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5-1
2. What’s GPRS All About? How Does It Fit In?
s GSM: Global System for Mobile Communication
• The world’s most widely used wireless phone technology
– Over 500,000,000 users worldwide!
– TDMA-based radio interface, 200 kHz.-wide signals
• But very limited data capability
– 9,600 or 14,400 bps maximum in circuit-switched mode
s WCDMA / UMTS: The Long-Term 3G Data Solution
• Uses spread-spectrum CDMA techniques, 4-MHz.-wide signals
• Provides both voice and high speed packet data access
• But not widely deployed and available until 2003 or later
s GPRS: General Packet Radio Service
• A packet-switched IP-capable way of using GSM radio infrastructure
• Defined in 1996, wide deployment beginning in 2001
• Provides both interim pre-WCDMA and long-term packet access
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5-2
3. Communications Technology Family History
A Story of Births, Weddings and Funerals
s Commercial telegraphy gave birth to telephony, then died
s Telephony and Land Mobile Radio married, giving IMTS & Cellular
s IP networks developed, their usage and bandwidth are increasing
s The wedding of IP and Wireless is happening now in 3G!
Land Mobile Radio Extinction?
HF, VHF, UHF, Trunked
IP Networks
The Internet Voice over IP
Wireless Voice and IP Data
IMTS-Cellular-GSM-GPRS-WCDMA
Commercial Switched Telephony Extinction?
Digital Switching
Commercial Telegraphy Extinction!
50 60 70 80 90 10 20 30 40 50 60 70 80 90 10 20 30 40 50
1800s 1900s 2000s
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5-3
4. GSM and GPRS
Background: GSM Technology
Background: GSM Technology
The Foundation of GPRS
The Foundation of GPRS
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5-4
5. The Beginnings of GSM
s 1980’s: Europe used variety of first generation analog cellular
systems: TACS, ETACS, NMT450, NMT900, Netz, etc.
• Operation was limited to various national boundaries
• Poor roaming capabilities, poor economies of scale in mfg.
s In 1982, CEPT the Conference of European Posts and Telegraphs
created a group to study and define a 2G Pan-European system
• Group Spécial Mobile (GSM)
• In 1989, administration of GSM was transferred to the
European Telecommunications Standards Institute (ETSI)
• In 1990, the GSM specification, Phase I, was published
s GSM has become very popular due to many positive factors
• Non-proprietary: anyone can manufacture networks/handsets
• Thorough/integrated standard: well-defined RF air interface,
network architecture, call delivery and roaming features
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5-5
6. GSM World Acceptance
s GSM commercial deployment began
in 1991
s By 1993, there were 36 GSM
networks in 22 countries
s In 2000, there were over 200 GSM
networks in over 110 countries
around the world
• Operation in 900 MHz., 1800
MHz., and 1900 MHz. bands
s The wide acceptance of GSM has provided tremendous
economies of scale in network, handset, and test equipment
manufacturing and distribution
s Worldwide in 2001, GSM users have passed the 500 million mark
• One in 12 human beings uses a GSM phone!
s The global dominance of GSM provides a large market for the
2.5G and 3G enhancements GPRS and UMTS WCDMA
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5-6
7. GSM vs. North American Standards
s Two different approaches to wireless technology development!
• Americans: Invent cool new stuff driven by market forces, write
standards if it works and the market accepts it
• Europeans: Study, Plan, build Standards, build Consensus, Plan,
Review, build more Consensus, finally Deploy
s The differences are visible in the resulting standards
• American: multiple interim standards necessary to define functionality
• Europeans: single integrated standard covers all functionality
North American CDMA GSM
Other Features IS-637 IS-683 IS-707 Etc.
SMS OTA Data
Intersystem Roaming, The GSM Standard
IS-41C, D, P
Call Delivery, Handoff One coordinated, uniformly
structured family of documents
Network Architecture IS-634 A-interface
Air Interface
IS-95/J-Std 008 CDMA
RF Architecture
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5-7
8. GSM Terminology
s Some terms have different
meanings when used in GSM
Sector or North American practice! Cell
α α
CELL Cell BTS Cell
Sector Sector
γ β γ β
It’s a Sector! It’s a Cell!
Sector Sector Cell Cell
γ β γ β
That was a Handoff! That was a Handover!
The frequencies used The frequencies used
by each sector are by each cell are
its channel set. its allocation.
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5-8
9. Structure of a GSM Signal
s GSM carriers are spaced 200 kHz.
apart
s In the BTS downlink signal, different 8 Slots
Required
1
2
C/I ≅ 9-12 dB
timeslots belong to different users - 4
3
a mobile listens only to its recurring
timeslots 200 kHz
Typical Frequency Reuse N=4
• During unused timeslots, a
mobile can measure the signal
strength of surrounding BTSs to
guide the handover process
s The mobile on its uplink transmits
only during its assigned timeslots
• Mobiles transmit only during BTS
their own timeslots
• Mobile transmit timeslots occur
three timeslots after the
corresponding BTS transmit
timeslot
– This avoids simultaneous
mobile TX/RX and the need
for duplexer at the mobile
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5-9
10. The Frequencies Used by GSM
Europe and International
GSM Uplink GSM Downlink
124 ch. 124 ch.
890 915 MHz. 935 960
North American PCS Licensed Blocks
A D B E F C1 C2 C3 A D B E F C1 C2 C3
75 ch. 25 75 ch. 25 25 25 25 25 75 ch. 25 75 ch. 25 25 25 25 25
1850 1865 1885 1900 1910 1930 1945 1965 1975 1990
MHz.
s GSM operates in a variety of frequency bands worldwide
s GSM carrier frequencies are normally assigned in 200 KHz.
Increments within the operator’s licensed block of spectrum
s Spectrum is provided in “blocks”
• Base stations transmit in the upper block
• Mobiles transmit in the lower block
s Each cell uses a certain number of carriers, called its “allocation”
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5 - 10
11. Multiple Carriers in a GSM Cell
Time
Frequency 6 TS1 TS2 TS3 TS4 TS5 TS6 TS7 TS8
Frequency 5 TS1 TS2 TS3 TS4 TS5 TS6 TS7 TS8
Frequency 4 TS1 TS2 TS3 TS4 TS5 TS6 TS7 TS8
Frequency 3 TS1 TS2 TS3 TS4 TS5 TS6 TS7 TS8
Frequency 2 TS1 TS2 TS3 TS4 TS5 TS6 TS7 TS8
Frequency 1 TS1 TS2 TS3 TS4 TS5 TS6 TS7 TS8
1 timeslot 577 µs
1 frame 4.515 ms
s A GSM base station transceiver makes a signal ~240 kHz. wide
s The signal is time-divided into a repeating pattern of frames
• Each frame is 60/13 = 4.515 ms long, there are ~221.5 frames per second
s Each frame is further subdivided into 8 timeslots, each 15/26 ms = 577 µs long
• A timeslot can hold the bits of a channel of information
– One user’s voice signal, or a signaling/administrative channel
s One GSM base station can have several transceivers, each one producing a
GSM signal on a different frequency - six carriers in the example above
• Various repeating patterns of information can use the timeslots to carry
channels of information
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5 - 11
12. Channels in GSM: Repeating Patterns
s Channels of information in GSM occupy physical timeslots of the GSM
signal in repeating patterns
• Similar to the way that classes and activities of a university occupy the
physical classrooms on a defined schedule
– Some classes meet daily, some only three days a week
– Some labs once or twice a week
– Meals daily in the cafeteria, movies on Friday nights
– Graduation ceremonies each semester
s Dedicated channels (carrying traffic or control information for individual
users) occur in a repeating 26-multiframe pattern 120 ms long
• 24 frames are used for traffic, one for SACCH, one is unused
• Full-rate TCHs occur in each traffic frame
• Half-rate TCHs (if used) occur in alternating traffic frames
• 1/8 rate dedicated channels are defined for special purposes and are
called SDCCHs (Stand-Alone Dedicated Control Channels)
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5 - 12
13. GSM Traffic Channels:
Hyperframes, Superframes, Multiframes, Frames, and Bursts
One Hyperframe
2048 superframes 3h 28m 53.760s
0 1 2 3 4 5 2044 2045 2046 2047
51 multiframes of 26 frames each 6.120 s
One
Superframe 0 1 2 3 4 5 6 47 48 49 50
UNUSED
TCHs SACCH TCHs
One 26 Used for traffic channels and
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
0 1 2 3 4 5 6 7 8 9
Multiframe associated signaling only
26 frames 120 ms
One
BP 0 BP 1 BP 2 BP 3 BP 4 BP 5 BP 6 BP 7
Frame
1 frame 60/13 ms ~4.615 ms
Stealing Stealing
One Burst (156.25 bits)
Bit Bit
Tail Bits
Tail Bits
Training Guard
Data Bits Data Bits Bits
Sequence
3 57 bits 1 26 bits 1 57 bits 3 8.25 bits
15/26 ms
Gross Rate 270.833 kbps ~0.577 ms
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5 - 13
14. GSM Control Channels:
Hyperframes, Superframes, Multiframes, Frames, and Bursts
One Hyperframe
2048 superframes 3h 28m 53.760s
0 1 2 3 4 5 2044 2045 2046 2047
26 multiframes of 51frames each 6.120 s
One
Superframe 0 1 2 3 24 25
not used
BCCH 1
BCCH 2
BCCH 3
BCCH 4
CCCH0 or
FCCH
FCCH
FCCH
FCCH
FCCH
SYS_INFO CCCH3 or CCCH4 or CCCH5 or CCCH5 or CCCH6 or CCCH7 or
SCH
SCH
SCH
SCH
SCH
7&8 CCCH 1 CCCH 2 SDCCH SDCCH SDCCH SDCCH SACCH SACCH
One 51 0
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
1 2 3 4 5 6 7 8 9
Multiframe
51 frames 235.38 ms
Used for control channels only
One BP 0 BP 1 BP 2 BP 3 BP 4 BP 5 BP 6 BP 7
Frame 1 frame 60/13 ms ~4.615 ms
Stealing Stealing
One Burst (156.25 bits)
Bit Bit
Tail Bits
Tail Bits
Training Guard
Data Bits Data Bits Bits
Sequence
3 57 bits 1 26 bits 1 57 bits 3 8.25 bits
15/26 ms
Gross Rate 270.833 kbps ~0.577 ms
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5 - 14
15. Typical Timeslot Allocation in Multiframe Patterns
on One GSM RF Carrier
TIME
S S
TimeSlot T T T T T T T T T T T T A T T T T T T T T T T T T T T T T T T T T T T T T A T T T T T T T T T T T T
IDLE
IDLE
C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C
7 H H H H H H H H H H H H C H H H H H H H H H H H H H H H H H H H H H H H H C H H H H H H H H H H H H
H H
S S
TimeSlot T T T T T T T T T T T T A T T T T T T T T T T T T T T T T T T T T T T T T A T T T T T T T T T T T T
IDLE
IDLE
C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C
6 H H H H H H H H H H H H C H H H H H H H H H H H H H H H H H H H H H H H H C H H H H H H H H H H H H
H H
S S
TimeSlot T T T T T T T T T T T T A T T T T T T T T T T T T T T T T T T T T T T T T A T T T T T T T T T T T T
IDLE
IDLE
C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C
5 H H H H H H H H H H H H C H H H H H H H H H H H H H H H H H H H H H H H H C H H H H H H H H H H H H
H H
S S
TimeSlot T T T T T T T T T T T T A T T T T T T T T T T T T T T T T T T T T T T T T A T T T T T T T T T T T T
IDLE
IDLE
C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C
4 H H H H H H H H H H H H C H H H H H H H H H H H H H H H H H H H H H H H H C H H H H H H H H H H H H
H H
S S
TimeSlot T T T T T T T T T T T T A T T T T T T T T T T T T T T T T T T T T T T T T A T T T T T T T T T T T T
IDLE
IDLE
C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C
3 H H H H H H H H H H H H C H H H H H H H H H H H H H H H H H H H H H H H H C H H H H H H H H H H H H
H H
S S
TimeSlot T T T T T T T T T T T T A T T T T T T T T T T T T T T T T T T T T T T T T A T T T T T T T T T T T T
IDLE
IDLE
C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C
2 H H H H H H H H H H H H C H H H H H H H H H H H H H H H H H H H H H H H H C H H H H H H H H H H H H
H H
Frame 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 2 3 4 5 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
1
Number
26 Multiframe Pattern for Traffic Channels 26 Multiframe Pattern for Traffic Channels
S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S
D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D A A A A A A A A A A A A A A A A
TimeSlot C
IDLE
IDLE
IDLE
C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C
C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C
1 H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H
0 0 0 0 1 1 1 1 2 2 2 2 3 3 3 3 4 4 4 4 5 5 5 5 6 6 6 6 7 7 7 7 0 0 0 0 1 1 1 1 2 2 2 2 3 3 3 3
A A A A A A A A A A A A S S S S S S S S S S S S S S S S S S S S
B B B B G G G G G G G G G G G G
TimeSlot F C C C C C C C C F C C C C C C C C F D D D D D D D D F C C C C D D D D F A A A A A A A A
C S C S S C C C C C C C C S C C C C S C C C C C C C C
IDLE
C C C C H H H H C C H H H H H H H H C C C C C C C C C C C C B B B B C C C C C C C C C C C C C C
0 C H H H H / / / / C / / / / / / / / C C C C C C C
H H H H H H H H H H H H H H H H H H H H H H H H H H
P P P P H P P P P P P P P H H H H H H H
1 2 3 4 C C C C C C C C C C C C 0 0 0 0 1 1 1 1 3 3 3 3 0 0 0 0 1 1 1 1
H H H H H H H H H H H H
Frame 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 3 3 3 3 3 3 3 3 3 3 4 4 4 4 4 4 4 4 4 4 5
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0
Number
51 Multiframe Pattern for Control Channels
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5 - 15
16. A GSM Uplink Normal Burst
s GSM is a TDMA system and a mobile’s transmission bursts are carefully
constructed not to overlap with bursts from other mobiles
s Different propagation delays of mobiles near and far mobiles the BTS are
compensated by automatically advancing mobile transmit timing
s Special training sequences are included in each uplink burst and downlink
timeslot to facilitate demodulation
s During unused timeslots, a mobile measures the strength of surrounding
base stations to guide the handover process (this is called MAHO, Mobile
Assisted Hand Over)
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5 - 16
17. GSM Bursts on the Uplink: 4 Types
Frequency Correction Burst or Dummy Burst
Guard
Tail
Tail
Fixed ‘0’ or Fill-in Bits
Bits
3 142 bits 3 8.25 bits
Synchronization Burst
Guard
Tail
Tail
Data Bits Training Bits Data Bits Bits
3 39 bits 64 bits 39 bits 3 8.25 bits
Access Burst
Tail
Tail Guard
Bits
Training Bits Data Bits Bits
8 41 bits 36 bits 3 68.25 bits
Stealing Stealing
Normal Burst Bit Bit
Guard
Tail
Tail
Data Bits Training Bits Data Bits Bits
3 57 bits 1 26 bits 1 57 bits 3 8.25 bits
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5 - 17
18. GSM Channels
DOWNLINK CHANNELS UPLINK CHANNELS
BTS identity, channel allocation,
BCCH frequency hopping sequences
Slotted aloha channel used to
FCCH Provides frequency reference
request network access RACH
Defines burst period boundaries
SCH and time slot numbering
Carries pages to mobiles,
PCH alerting of incoming calls
Stand Alone Dedicated
AGCH
Allocates SDCCH to mobile to
Control Channel SDCCH
obtain dedicated channel after
a request on the RACH
Traffic Channel TCH
Fast Associated Control
BTS Channel FACCH
Slow Associated Control
Channel SACCH
0 to many F-TRAFFIC
Stand Alone Dedicated
SDCCH Control Channel
Traffic Channel
TCH
Fast Associated Control Channel
FACCH
Slow Associated Control Channel
SACCH
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5 - 18
19. The GPRS Timeslot Allocation
s In conventional GSM, a channel is permanently allocated for a particular
user during the entire call period (whether speaking or silent, whether
transmitting data or not)
• In GPRS, the channels are only allocated when data packets are
transmitted or received, and they are released after the transmission
• For bursty traffic this results in much more efficient use of the scarce
radio resources
• Multiple users can share one channel
s GPRS allows a single mobile to
transmit and/or receive on multiple
timeslots of the same frame (this is
called multislot operation)
• This provides “bandwidth on BTS
demand” in a very flexible
scheme
• One to eight timeslots per frame
can be allocated to a mobile
• Uplink and downlink allocations •This GPRS mobile is in “3+1” timeslot mode
•3 timeslots assigned on downlink
can be allocated separately, •1 timeslot assigned on uplink
which efficiently supports
asymmetric data traffic (suitable
for web browsing, for example)
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5 - 19
20. Allocation of GPRS Channels
s A cell supporting GPRS may allocate physical channels for GPRS traffic
s Such a physical channel is denoted a Packet Data Channel (PDCH)
• The PDCHs are taken from the common pool of all channels available
in the cell
• The radio resources of a cell are shared by all GPRS and all non-
GPRS mobiles in the cell
• The mapping of physical channels to either GPRS or GSM usage can
be performed dynamically, based on:
– Capacity on demand principle
– Depending on the current traffic load, priority of service, and the
multislot class
s A load supervision procedure monitors the PDCHs in the cell
s The number of channels allocated to GPRS can be changed according to
current demand
• Physical channels not currently in use by conventional GSM can be
allocated as PDCHs to increase the GPRS quality of service
• When there is a resource demand for services with higher priority,
PDCHs can be de-allocated
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5 - 20
22. 3 Steps to 3G: The GSM Transition
GSM TODAY
PLMN Core Network SIM
PSTN MSC BSC BTS Mobile
VLR Base Base
Gateway Mobile Station
ISDN Station Transceiver
Switching Controller Stations
MSC Mobile
HLR Center
Equipment
Internet
2.5G: GSM + GPRS
Core Network
VLR MSC
PLMN Mobile SIM
PSTN Gateway Switching Mobile
MSC Center
BSC BTS
HLR Base Base
Station
ISDN Gateway Serving Station Transceiver Mobile
GPRS GPRS PCU Controller Stations Equipment
Support Support
Internet node node
3G: UMTS, UTRA
Core Network MSC UTRAN
RNC Node B UMTS
PLMN VLR Mobile
PSTN Gateway Switching Radio SIM
Network
MSC Center Controller Node B User
ISDN HLR Equipment
Gateway Serving RNC
GPRS GPRS Radio Node B Mobile
Internet Support Support Network Equipment
node node Controller Node B
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5 - 22
23. Architecture of a Phase-1 GSM Network
PLMN Core Network SIM
PSTN MSC BSC BTS Mobile
VLR Base Base
Gateway Mobile Station
ISDN Station Transceiver
Switching Controller Stations
MSC Mobile
HLR Center
Equipment
Internet EIR AuC A Abis Um
Interface Interface Interface
GSM Functional Entities and Network Elements
PLMN - Public Land Mobile Network HLR - Home Location Register
PSTN - Public Switched Telephone Network VLR - Visitor Location Register
ISDN - Integrated Services Digital Network BSC - Base Station Controller
GMSC - Gateway Mobile Switching Center BTS - Base Transceiver Station
MSC - Mobile Switching Center SIM - Subscriber Identity Module
EIR - Equipment Identity Register ME - Mobile Equipment
AuC - Authentication Center MS - Mobile Station
s The network elements and interfaces of GSM are standardized
s This provides for inter-vendor participation in operators’ networks
• Competition improves quality, provides economies of scale
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5 - 23
24. GSM Network Evolution and History
GSM TODAY
PLMN Core Network SIM
PSTN MSC BSC BTS Mobile
VLR Base Base
Gateway Mobile Station
ISDN Station Transceiver
Switching Controller Stations
MSC Mobile
HLR Center
Equipment
Internet
s The present GSM network architecture emerged from work of the
ETSI in the late 1980s
s The GSM network can be divided into three main domains
• The Network Switching Subsystem (GMSC, VLR, HLR, MSC)
• The Operations and Support Subsystem (not shown, includes
OMC-R)
• The Base Station Subsystem BSS (includes BSCs, BTSs)
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5 - 24
25. GSM Evolution: General Packet Radio Service
s Around 1994, the GSM phase 2 standards were enhanced to
include a number of new and improved services. These
enhancements became known as GSM Phase 2 Plus.
s One of the new features proposed in 1994 was a new bearer
service, true packet radio service known as GPRS
s GPRS allows a user with suitable mobile station to occupy multiple
time slots on a TRX, culminating in the possible occupancy of all 8
timeslots if they are available
• Data rates supported per timeslot are 9.06, 13.4, 15.6, and
21.4 kb/s
• When all 8 timeslots are available, throughput can reach 8 x
21.4 kb/s = 171.2 kb/s, although realistic expectations are
around 115 kb/s due to BCCH and other requirements
s GPRS applications are expected to include internet access/web
browsing, video and Road Traffic and Transport Informatics
(RTTI), and e-commerce and point-of-sale accounting
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5 - 25
26. GPRS Network Architecture
VLR LEGEND
PLMN
PSTN MSC
Existing GSM Core Network elements
ISDN A New GPRS elements and interfaces
User data & signaling
Gs Signaling only
SGSN
of a HLR EIR SMSC
different SIM
PLMN Gp Ater Mobile
Gc Gr Gf TCU BSC BTS Station
Gd Base Abis Base
Station Transceiver Mobile
Controller Station Eqpm’t
PSPDN PCUSN
GGSN Gn SGSN Gb Agprs
Gi
Um
Interface
s The GSM network architecture was modified to add packet services, through the
addition of the new network elements GGSN and SGSN
• GGSN Gateway GPRS Support Node
– Responsible for routing data packets entering and leaving the radio
network; also as a router for packets within the network
• SGSN Serving GPRS Support Node
– responsible for packet delivery to mobiles in its area
– a type of packet switch with capability to interrogate the GSM
databases HLR and VLR for location and service profiles of mobiles
s Data is “tunneled” from the GGSN to the SGSN using GTP, GPRS Tunneling
Protocol, encapsulating packets de-encapsulating on delivery
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5 - 26
27. Understanding the Backbone Networks
VLR LEGEND
PLMN
PSTN MSC
Existing GSM Core Network elements
ISDN A New GPRS elements and interfaces
User data & signaling
Gs Signaling only
SGSN
of a HLR EIR SMSC
different SIM
PLMN Gp Ater Mobile
Gc Gr Gf TCU BSC BTS Station
Gd Base Abis Base
Station Transceiver Mobile
Controller Station Eqpm’t
PSPDN PCUSN
GGSN Gn SGSN Gb Agprs
Gi
FRAME RELAY Um
IP or X.25 Interface
s Gb between SGSN-PCUSN uses Frame Relay protocols
s Gn between SGSN-GGSN uses IP routing, GPRS Tunnel Protocol
s Gr between SGSN-HLR is an extension of MAP
s Gi between GGSN and PDNs uses IP and X.25
s Gd between SGSN-SMSC delivers SMS messages using MAP
s Gc between GGSN-HLR is optional, uses MAP
s Gs between SGSN-MSC/VLR is optional, uses BSSMAP
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5 - 27
28. GPRS Backbone Networks
s Two kinds of GPRS
backbones:
• Intra-PLMN among
GSNs of same PLMN
(private, IP-based)
• Inter-PLMN among
GSNs of different
PLMNs (roaming
agreements)
s Gateways between the
PLMNs and the external
inter-PLMN backbone are
called Border Gateways
• Border Gateways perform security functions to prevent unauthorized
access and attacks
s The Gn and GP interfaces are also defined between two SGSNs
• This allows exchange of user profiles as mobiles move around
s The Gf interface allows a SGSN to query the IMEI of a registering mobile
s The Gi interface connects the PLMN to external public or private PDNs
• Interfaces to IPv4, IPv6, and X.25 networks are supported
s The Gr interface allows an SGSN to communicate with an HLR
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5 - 28
29. GPRS-GSM Coordination
s The MSC/VLR may be
extended with functions
and register entries for
efficient coordination
between GPRS packet
switched and GSM
circuit-switch services
• Combined GPRS
and non-GPRS
location updates
s Paging requests for circuit-switched GSM calls can be performed via
the SGSN
• The Gs interface connects the databases of SGSN and MSC/VLR
s The Gd interface allows short message exchanges via GPRS
• Gd interconnects the SMS gateway MSC (SMS-GMSC) with the
SGSN
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5 - 29
30. GPRS Services
s GPRS bearer services provide end-to-end packet-switched data transfer.
There are two kinds:
s PTP Point-to-Point Service, available now, has two modes:
• PTP Connectionless Network Service (PTP-CLNS) for IP
• PTP Connection-oriented network Service (PTP-CONS) for X.25
s PTM Point-to-Multipoint Service (available in future releases)
• PTM-M Multicast Services broadcasts packets in certain geographical
areas; a group identified indicates whether the packets are intended
for all users or for a group
• PTM-G Group Call Service addresses packets to a group of users
(PTM group) and are sent out in geographical areas where the group
members are currently located
s SMS Short Message Services
s Supplemental Call Services:
• CFU Call Forwarding Unconditional, CFNRc Call Forwarding
Subscriber Not Reachable, CUG Closed User group
s Non-Standard Services may be offered at GPRS service providers
• Database access, messaging, e-transactions, monitoring, telemetry
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5 - 30
31. The Stages of the GPRS Specifications
Stage 1
s The GPRS specification is 02.60 GPRS Service Description (overview)
built in three stages
s Stage 1 describes the basic Stage 2
GPRS Service Description
service capabilities 03.60
(System and Architecture)
03.64 Radio Interface Description
s Stage 2 describes the specific
system and network Stage 3
architectures and the radio 04.60 MS-BSS: RLC/MAC layer descriptions
interface description 04.64 MS-SGSN: Logical Link Control
04.65 MS-SGSN: SNDCP
s Stage 3 provides details of the 07.60 GPRS Mobile Stations
link control layer entities, 08.14 Gb (BSS-SGSN) layer 1
specifications of the mobile 08.16 Gb (BSS-SGSN) network service
08.18 Gb (BSS-SGSN) BSSGP
stations, and details of the
09.16 Gs (MSC/VLR-SGSN) layer 2
internal network element 09.18 Gs (MSC/VLR-SGSN) layer 3
interfaces and their protocols 09.60 Gn and Gp GPRS Tunneling Protocol
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5 - 31
32. GPRS Initial Release Features
s All network manufacturers are expected to support IP and
interworking with both internet and intranet in their first product
release
• To support this functionality, some form of server functionality
must be provided
– Domain Name Server (DNS) is required to translate
between domain names and IP addresses
– Dynamic Host Configuration Protocol (DHCP) is required to
allow automatic reassignment of addresses for mobile
hosts
s In early networks, a single SGSN will probably be sufficient due to
the gradual growth of users and traffic as mobiles become
available
s The connection between the GGSN and the MSC/VLR, HLR, and
SMSC will require a gateway using SS7/IP or SIG to link the IP
backbone with the interfaces to these network elements
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5 - 32
33. GPRS
A Closer View of the GPRS
A Closer View of the GPRS
Internal Interfaces and Elements
Internal Interfaces and Elements
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5 - 33
34. Serving GPRS Support Node (SGSN) Functions
s The Serving GPRS Support Node
(SGSN) is responsible for the following
to and from the mobile stations in its
service area:
• Packet Routing and Transfer
• Mobility management (attach/detach
and location management)
• Logical Link management
• Authentication and charging
functions, encryption
• Compression (optional)
• Location register of SGSN stores
location (cell, vlr) and user profiles
s A typical PLMN network will start with
only one SGSN
s Each BSC has a Packet
Communications Unit, PCU Several models of the
Nortel Passport Switch
• Similar hardware provides the for SGSN and PCUSN service
PCUSN function
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5 - 34
35. Gateway GPRS Support Node (GGSN) Functions
s The Gateway GPRS Support Node
(GGSN) is the interface between
external packet data networks and
GSM backbone network
• Converts GPRS packets from
the SGSN into packet data
protocol format (IP, X.25) for Nortel’s GGSN:
the external networks Bay Contivity Extranet Switch
• Converts PDP addresses of CES-4500
incoming data packets to GSM
address of destination user,
and forwards to responsible s Initial GPRS traffic in a PLMN
SGSN network will be low, and a single
GGSN will suffice for first service
• GGSN stores the current SGSN and an appreciable time
address of the user and the thereafter
user’s profile in its location
register
• GGSN performs authentication
and charging functions
• Performs tunneling
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5 - 35
36. GSM BTS Changes Required to Support GPRS
Three Possible GPRS BSS Configurations
s Since GPRS uses new coding Um Gb
schemes, a Channel Codec Interface Interface
Unit (CCU) is required CCU BTS BSC
PCU
• The CCU can normally be CCU
SGSN
implemented within BTS
software PCU in BTS
Advantage: short Round Trip Delay
s Timeslot allocation for GPRS Abis
is handled by a new Packet Interface
Controller Unit (PCU) which CCU BSC
also implements frame relay CCU
BTS PCU SGSN
connection with the GPRS
network PCU in BSC
• The PCU function can be Gb
physically implemented in Interface
the BTS, BSC, or at the CCU BSC
SGSN, but is conceptually CCU
BTS PCU SGSN
part of the BSS
PCU at SGSN
Advantage: Leverage -- 1 PCUSN can manage multiple BSCs
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5 - 36
37. Channel Coding Implemented at the BTS
GPRS Coding Schemes
Pre- Infobits Parity Tail Output Punct Code Data
Coding Cod. Without Bits Bits Conv. ured Rate Rate
Scheme USF USF BC encoder Bits Kbit/s
CS-1 3 181 40 4 456 0 1/2 9.05
CS-2 6 268 16 4 588 132 ~2/3 13.4
CS-3 6 312 16 4 676 220 ~3/4 15.6
CS-4 12 428 16 456 1 21.4
s Channel coding is used to protect the transmitted GPRS data
packets against errors
• The channel coding in GPRS is very similar to that of GSM
– An outer block coding, an inner block coding, and an
interleaving scheme are used
s Four different coding schemes are defined in the table above
s As of mid-2001, network manufacturers were only implementing
CS-1 and CS-2
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5 - 37
38. The MS-SGSN Interface
s Packet Controller functions are provided by
the PCU, which is implemented in a
Physical BSC A VLR
physical PCUSN in the BSS TCU
Ater MSC
• The PCUSN handles the GPRS-
specific packet processing using frame Gb
relay protocols BSC PCUSN SGSN
Agprs
• The PCUSN connects to the BSC with
network manufacturers’ proprietary Agprs
BTS
interfaces
• The PCUSN connects to the SGSN via
the standard-defined Gb interface MS
s Although a PCUSN can optionally serve
more than one BSC, all channels from one PCUSN and PCU Distinction
•A PCUSN (Packet Controller Unit Serving
BSC must pass through the same PCUSN Node) is the hardware unit which implements
s TRAU frames from the mobile pass through the PCU (Packet Controller Unit) function
the BTS to the BSC and on into the PCUSN
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5 - 38
39. MS-SGSN Logical Link Control (LLC)
GMM SNDCP SMS GMM SNDCP SMS
LLC LLC
Relay
RLC RLC BSSGP BSSGP
MAC MAC Network Svc Network Service
GSM/RF GSM RF L1 L1
MS Um BSS Gb SGSN
s LLC provides the reliable link between MS and SGSN
s LLC supports these layer-3 Protocols:
• SNDCP Sub-Network Dependent Convergence Protocol
• GMM/SM GPRS Mobility & Session Management
• SMS Short Message Service
s Protocols supported by the LLC provide:
• Data ciphering for security
• Flow control; sequential order of delivery; error detection/recovery
• Acknowledged and Unacknowledged data transfer modes
s The LLC provides transparency - the lower level radio link protocols are
not involved and do not affect the GPRS applications running above
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5 - 39
40. MS-SGN Service Access Points (SAP) for LLC
s The LLC provides six service access points (SAP) to the upper
layers
• Each SAP has its own Service Access Point Identity (SAPI)
s The SAPs include:
• GMM/SM - Service for Signaling for Session/Mobility
Management
• SMS - Short Message Service
• QoS1 Packet Transmission SNDCP access
• QoS2 Packet Transmission SNDCP access
• QoS3 Packet Transmission SNDCP access
• QoS4 Packet Transmission SNDCP access
s Frames are assembled/disassembled using a multiplex procedure
• A logical link management entity (LLME) manages resources
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5 - 40
41. The Gb Interface: PCU-SGSN
SMS-GMSC OTHER
SMS-IWMSC GPRS PLMN
s The SGSN and the PCUSNs of each BSC Gd Gp GG
SN
are linked by a backbone network using SG
Frame Relay protocol over the Gb interface BTS BSC
Gb SN
GG Gi
• Data rate can be up to 2 Mbps Gf Gn SN
BTS Gs Gr PDN
• Frame relay protocol implementation is
actually simpler than X.25 Gc
EIR
s Layers at each node of the Gb : MS
MSC D HLR
• Physical Layer VLR
• Network Service Layer (NS)
• Base Station Subsystem GPRS
Protocol (BSSGP)
• Network Management (NM)
– GPRS Mobility Management
(GMM)
– LLC/Relay
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5 - 41
42. PCU and SGSN Operation over the Gb Interface
s BSSGP: Base Station Subsystem
GPRS Protocol
User Packets User Packets
• Provides flow control, manages Via RLC and Via RLC and
buffers, provides services for
MAC layers MAC layers
the higher layers
s GMM - GPRS Mobility Management Relay GMM NM LLC GM NM
• Manages mobility features for
users, such as location updating BSSGP L3 BSSGP
and paging L2
s NM - Network Management Network Services Frame
Relay
Network Services
• Manages flow control, buffers, Gb
virtual pathways between Physical Physical
PCU/SGSN PCU SGSN
s Network Services
• Implements the communications
protocol for the Gb interface
(Frame Relay)
s Physical Layer
• Hardware and physical nature
of the interface
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5 - 42
43. The Gn Interface: SGSN-GGSN
SMS-GMSC OTHER
SMS-IWMSC GPRS PLMN
s The SGSN and GGSN are linked by a Gd Gp GG
SN
GPRS backbone using IP routing SG
BTS BSC
s The Gn interface creates and operates Gb SN
GG Gi
through secure tunnels, using the Gf G SN
Gr n
GPRS Tunneling Protocol (GTP) BTS Gs PDN
s The GTP packet headers include EIR
Gc
• Tunnel endpoint and group identity MS
MSC D HLR
• PDU type VLR
• QoS parameters
• Routing protocol identification
– Static, RIP2, OSPF
s Beneath IP, any transport architecture
can be used
• Ethernet, Token-Ring, FDDI, ISDN,
ATM
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5 - 43
44. The Gp Interface: SGSN - Other PLMN GGSN
SMS-GMSC OTHER
SMS-IWMSC GPRS PLMN
s The Gp interface connects an SGSN of Gd Gp GG
SN
one PLMN with a GGSN of another SG
BTS BSC
PLMN Gb SN
GG Gi
Gf Gn SN
s This interface forms an inter-PLMN BTS Gs Gr PDN
backbone providing mobile IP Gc
capability for roaming mobiles EIR
MS
s Specific configuration of this link MSC D HLR
VLR
depends on the features intended by
the two PLMN operators, as well as
dimensioning issues
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5 - 44
45. More About GPRS Tunneling on Gn and Gp
GPRS TUNNELING PROTOCOL (GTP) SMS-GMSC OTHER
SMS-IWMSC GPRS PLMN
PROTOCOL STACK
Gd Gp GG
IP SN
GMM/SM SNDCP GTP GTP SG
IP BTS BSC SN
LLC UDP/TCP Gn, Gp UDP/TCP Gb GG Gi
BSSGP IP IP Gf Gn SN
NS L2 L2 L2 BTS Gs Gr PDN
L1B1s L1 L1 L1 Gc
EIR
SGSN GGSN
MS
MSC D HLR
VLR
s GPRS Tunneling Protocol (GTP) is used to carry user packets
between nodes
• GTP allows various protocols and is adaptable to both inter-
and intra-PLMN GGSN interfaces
– UDP/IP if reliable link is not required, TCP/IP if required
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5 - 45
46. The Gn Interface: SGSN-GGSN
SMS-GMSC OTHER
SMS-IWMSC GPRS PLMN
s The SGSN and GGSN are linked by a Gd Gp GG
SN
GPRS backbone using IP routing SG
BTS BSC
s The Gn interface creates and operates Gb SN
GG Gi
through secure tunnels, using the Gf G SN
Gr n
GPRS Tunneling Protocol (GTP) BTS Gs PDN
s The GTP packet headers include EIR
Gc
• Tunnel endpoint and group identity MS
MSC D HLR
• PDU type VLR
• QoS parameters
• Routing protocol identification
– Static, RIP2, OSPF
s Beneath IP, any transport architecture
can be used
• Ethernet, Token-Ring, FDDI, ISDN,
ATM
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5 - 46
47. The Gi Interface: GGSN-PDN
SMS-GMSC OTHER
SMS-IWMSC GPRS PLMN
s If the Gi interface is implemented via a Gd Gp GG
SN
public network, IP Security Protocol SG
(IPSEC) can be used to provide link BTS BSC
Gb SN
GG G
authentication and encryption Gf Gn SN i
• This allows use of public networks BTS Gs Gr PDN
such as the internet while Gc
maintaining confidentiality of data EIR
MS
s The GGSN creates VPN tunnels using MSC D HLR
VLR
security protocols like IPSEC if needed
s Four tunneling protocols are available:
• PPTP (client-initiated)
• L2F, L2TP (implemented on ISP
side)
• IPSec (layer-3 secure protocol)
s Transparent and Non-Transparent
modes are available
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5 - 47
48. The Gr Interface: SGSN-HLR
SMS-GMSC OTHER
SMS-IWMSC GPRS PLMN
s The Gr interface is an extension of the Gd Gp GG
SN
GSM-MAP (mobile application part) SG
BTS BSC SN
s Most network manufacturers use an Gb GG Gi
Gf Gn SN
SS7 gateway element to provide BTS GsG PDN
interworking between the GPRS r
Gc
network and the SS7-based voice EIR
network MS
MSC D HLR
VLR
• This relieves the SGSN from having
to do SS7 processing
• The SS7 gateway can be a
conventional server, usually with
redundancy features on both the
SGSN (IP) and SS7 sides
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5 - 48
49. The Gd Interface: SGSN-SMCS GMSC/IWMSC
SMS-GMSC OTHER
SMS-IWMSC GPRS PLMN
s The Gd interface delivers SMS Gd Gp GG
SN
messages via GPRS in the same SG
BTS BSC
manner as the GSM-MAP Gb SN
GG Gi
Gf Gn SN
BTS Gs Gr PDN
Gc
EIR
MS
MSC D HLR
VLR
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5 - 49
50. The Gf Interface: SGSN-EIR
SMS-GMSC OTHER
SMS-IWMSC GPRS PLMN
s The Gf interface connects the SGSN Gd Gp GG
SN
and the Equipment Identity Register SG
BTS BSC
(EIR) Gb SN
GG Gi
Gf Gn SN
BTS Gs Gr PDN
Gc
EIR
MS
MSC D HLR
VLR
10-2001 GSM 2.5G Migration: GPRS v1.28 (c)2001 Scott Baxter 5 - 50
51. The Gs Interface: SGSN-MSC/VLR
SMS-GMSC OTHER
SMS-IWMSC GPRS PLMN
s The Gs interface is optional Gd Gp GG
SN
• Provides simultaneous GPRS and BTS BSC
SG
SN
GSM operation between SGSN and Gb GG Gi
Gf Gn SN
MSC/VLR (same as BSSMAP but BTS Gs Gr PDN
optional) Gc
EIR
MS
MSC D HLR
VLR
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52. The Gc Interface: GGSN-HLR
SMS-GMSC OTHER
SMS-IWMSC GPRS PLMN
s The Gc interface is optional Gd Gp GG
SN
• Provides the same functions as the BTS BSC
SG
SN
MAP between GGSN and HLR Gb GG Gi
Gf Gn SN
BTS Gs Gr PDN
Gc
EIR
MS
MSC D HLR
VLR
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53. The D Interface: MSC/VLR - HLR
SMS-GMSC OTHER
SMS-IWMSC GPRS PLMN
s The MAP-D interface is used by both Gd Gp GG
SN
GSM and GPRS networks to SG
BTS BSC
communicate between the HLR and Gb SN
GG Gi
the VLR in the MSC Gf Gn SN
BTS Gs Gr PDN
s This link is specified in the GSM-MAP Gc
and is not changed in GPRS EIR
MS D HLR
MSC
VLR
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54. Quality of Service
Reliability
Probability of
Service Precedence Lost Dupli- Out-of Corrupt-
Class
High Packet cated Sequence ed
Packet Packets Packets
Medium 1 109 109 109 109
2 104 105 105 106
Low 3 102 105 105 102
s Mobile packet applications have a wide range of reliability expectations --
real-time multimedia, Web browsing, email transfer
s QoS Classes settable per session are a very important feature
• Service Precedence
– Priority of a service in relation to other services
• Reliability
– Required transmission characteristics (3 classes defined)
• Delay
– Maximum values for mean delay and 95-percentile delay
• Throughput
– Maximum-Peak bit rate and the mean bit rate
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55. Quality of Service: the Delay Parameter
Delay
128 byte packet 1024 byte packet
Class Mean 95% Mean 95%
Delay Delay Delay Delay
1 <0.5s <1.5s <2s <7s
2 <5s <25s <15s <75s
3 <50s <250s <75s <375s
4 Best Effort Best Effort Best Effort Best Effort
s Using these QoS Classes, QoS profiles can be negotiated
between the user and the network for each session, depending
on QoS demand and currently available resources.
• Billing is based on data volume, type of service, and QoS
profile
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56. Mobile Classes and Simultaneous Usage
s In a GSM network, two classes of service can run concurrently:
• Circuit-Switched Services (speech, data, and SMS)
• Packet-Switched Services (GPRS)
s Three Classes of Mobile Stations are defined:
• Class A mobiles
– Support simultaneous operation of GPRS and conventional GSM
services, but two separate radio chains are required
• Class B mobiles
– Able to register with the network for both GPRS and conventional
GSM services simultaneously, but can only use one of the two
services at a given moment - voice can pre-empt data
• Class C mobiles
– Able to attach for either conventional GSM or GPRS, manually
switched
– Simultaneous registration (and usage) is not possible, except for
SMS messages which can be received and sent at any time
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