Dr. Tanuja Patgar-Cellular System Components.pptx

It consists of several sub systems or network elements

1. Mobile or Subscriber Device- providers the user link to wireless network.

2.Base Station - provides wireless system links to the subscriber over air interface


3.Network Switching System -provides interface to the PSTN and PDN

1. Common Cellular System Components Unit-2 Dr. TANUJA P B.Tech , M.tech , PhD, Post Doc Department of Electronics and Communication Dr. AIT, Bangalore

2. Wireless Cellular System Component

3. A Typical (1G) wireless cellular telecommunication system is shown in fig.1 It consists of several sub systems or network elements 1. Mobile or Subscriber Device- providers the user link to wireless network. 2. Base Station - provides wireless system links to the subscriber over air interface 3. Network S witching S ystem - provides interface to the PSTN and PDN Wireless Cellular System Component

4. Mobile Station or Subscriber device -- that provide user mobility. 2. R adio Base Station - Controlled by a base station controller which is referred as base station system. 3. Base Station System – C onnected to a fixed switching system that handles the routing of both voice calls and data services It handles all radio interface related functions for the wireless network . It consists of several to many radio base stations , a base station controller , Transcoder controller . radio equipment required to serve one cell is typically called a base transceiver system. Wireless Cellular System Component

5. 1. VISITOR LOCATION REGISTER: The database that temporarily stores information about any mobile station that attaches to a RBS in the area services by a particular MSC. This temporary subscriber information is required by the MSC to provide service to a visiting subscriber . 2. HOME LOCATION REGISTER: The data base that stores information about every user that has a cellular service contract with specific wireless service provider . This database stores permanent data about the networks subscribers, information about the subscribers present location. 3. AUC Interconnection It provides authentication and encryption information for the MS being used in the cellular network. Registers in Wireless Cellular System

6. 4. EQUIPMENT IDENTITY REGISTER: Used to validate then status of mobile equipment . This global database is updated daily to reflect the current status of an MS. 5. INTERWORKING UNITS: Required to provide an interface to various data networks. These nodes are used to connect the base station controller and hence the radio base stations to various data services networks. Switching System – It is usually connected to the PSTN , the PDN , other public land mobile networks(PLMN ) and various data messaging networks through gate way switches. Registers in Wireless Cellular System

7. INTERWORKING UNITS: Required to provide an interface to various data networks. These nodes are used to connect the base station controller and hence the radio base stations to various data services networks.   GATEWAYS Gateway MSC: (GMSC) It interfaces the wireless mobile network to other telecommunication networks. Billing Gateway : (BGW) -- It collects billing information from various wireless network elements which becomes a file use by customer administrative system to generate billing information for the system subscribers like monthly access fees, home usage , roaming , data and special services etc. Service Order Gateway :(SOG) It is used to connect a customer administrative system to the switching system. This system is used to input new subscriber data to the HLR or to update current subscriber data already contained in the HLR. Registers in Wireless Cellular System

8. Subscriber Devices

9. Link between the customer and wireless network. Must be able to provide a means for the subscriber to control and input information to the phone and display its operational status. It must be able to sample, digitize and process audio and other multimedia signals. Transmit and receive RF signals, Process system control messages etc., The basic sections of SD are:- (1) Man – Machine interface (2) RF transceiver section (3) Signal processing section (4) A system control processor (5) Power supply / management section Subscriber Devices

10. Base Station System (BSS)Components

11. Base Station System (BSS)Components Handles all radio interface-related functions for the wireless network. BSS consists of- (1) Many radio base stations(RBS’s) – includes - Antennas, transmission lines - power couplers - RF power amplifiers - tower mounted preamplifiers - other associated hardware (2) Base Station Controller(BSC)-Supervises the operation no. of RBS’s (3)Trans-coder Controller(TRC) – performs rate adaptation- VOCODER

12. Radio Base Station(RBS) Consists of all radio and transmission interface equipment needed to establish a radio link with the MS. 2 types (1) TDMA RBS (2) CDMA RBS TDMA RBS- Consists of - Distribution switch - Multiple transceiver units - RF combining and distribution units - Energy control unit - Power supply components CDMA RBS – Consists of - same as that of TDMA RBS - Timing and frequency module - Channel cards

13. Base Station Controller(BSC) (Typical block diagram of CDMA BSC)

14. Base Station Controller(BSC) System description and Interface Operation and Protocol

15. Transcoder Controller Consists of subsystems that perform transcoding and rate adaptation TRC can be either a standalone unit or combined with BSC to yield an integrated BSC / TRC

16. Switching System Components(NSS) Visitor Location Register(VLR) Mobile Switching Center(MSC) Home Location Register(HLR) Interworking Location Register(ILR) Gateway MSC Authentication center(AUC) Equipment Identity Register(EIR) Interworking Units(IWU)

17. Visitor Location Register(VLR) Data base that temporarily stores information about any MS that attaches to a RBS in the area serviced by a particular MSC In a typical wireless network, the VLR is integrated with MSC to form an MSC/VLR, thus reducing amount of SS7 n/w signaling necessary to perform n/w operations