Umts to gsm or umts to gprs umts supports a variety of user data rates and both packet and circuit switched services system composed of three main subsystems telcom 2720 4 umts system architecture ue user equipment that interfaces with the user utran umts terrestrial radio access network handles all radio. It has an open, distributed architecture the separation of switching and service control functions full use of ss7 as the signaling infrastructure its clearly defined and specified interfaces. The 2g gsm network architecture, although now superseded gives an excellent introduction into some of the basic capabilities required to set up a mobile communications phone network and how all the entities operate together. A base station antenna carrying 2g gsm signals gsm network architecture elements. The user terminals of the mobile networks are the mobile stations ms. Architecture, security and future challenges ihtesham ul haq 1, zia ur rah man 2, shahid ali 3, engr. This tutorial provides an introduction to basic gsm concepts, specifications, networks, and services. It can be viewed as a computerized monitoring center were staff can monitor and control the network remotely in the gsm network, the implementation of the omc is called the operation and support system oss. In the r4 network, msc as the cs domain of the cn is divided into the msc server and the mgw, at the same time, a sgw is added, and hlr can be replaced by hss not explicitly specified in the specification.
Evolutionary analysis of gsm, umts and lte mobile network. Often described as a true intelligence network, gsm is called the first true wireless network because. The global system for mobile communications gsm is a standard developed by the european telecommunications standards institute etsi to describe the protocols for secondgeneration digital cellular networks used by mobile devices such as mobile phones and tablets. Page 4 of 16 each arfcn channel is a duplex channel and consists of an up and a down links. By the mid2010s, it became a global standard for mobile communications. Because of that, umtss and gsmedges radio access networks are sometimes collectively referred to as utrangeran. Gsm is the short form of global system for mobile communications. Geographical structures in a mobile communication network gsm is a worldwide standard for mobile communication with an extensive coverage. Due to the mobility of the subscribers, the organisational structure must be subdivided into different processing elements. In terms of the osi reference model, the radio signal operates at the physical layer, and the data format controls several of the higher layers. A short history of network evolution is provided in order set the. Study and learn interview mcq questions and answers on 2g gsm structure architecture basics. The gsm frame structure is designated as hyperframe, superframe, multiframe and frame. Gsm association roaming database, structure and updating.
Umts and gsmedge can share a core network cn, making utran an alternative radio access network to geran gsmedge ran, and allowing mostly transparent switching between the rans according to available coverage and service needs. A gsm modem requires a sim card to be operated and operates over a network range subscribed by the network operator. The minimum unit being frame or tdma frame is made of 8 time slots. L over 400 gsm network operators l over 550 million people were subscribers to gsm. Introduction to wireless networks when you invent a new network. The network structure includes the wireless network interface adapters and base stations that send and receive the radio signals. Each cell is given a cell global identity cgi, a number that uniquely identifies the cell. Hence there will be total of 2715648 tdma frames available in gsm and the same cycle continues. An overview of a gsm network architecture is presented in figure 3.
Oss is the functional entity from which the network operator can monitor and control the entire mobile network. Strictly defined interface determines how the functions are proceeding in the network and which functions are implemented internally by. The global system for mobile communications gsm which is a standard for 2g second generation cellular networks has created an avenue for the development of 3g third generation and 4g fourth generation cellular network standards such as universal mobile telecommunications system umts and long term evolution lte. Gsm network interfaces list a series of different interface definitions were written and each given names as seen below. Pdf availability analysis of gsm network systems researchgate. Cellular concept several small cells instead of a single transmitter frequency reuse.
Telecommunications network and service architectures. It initially started as a circuit switching network, but later packet switching was implemented. This is explained below in tdma gsm frame structure. The coverage area of cdma is more limited than gsm. By standard the gsm network is divided into four 4 subsystems. The gsm standard was developed for setting protocols for second generation 2g digital cellular networks. This basic tutorial on gsm architecture also covers gsm burst types, gsm frame structure, gsm channels, gsm physical layer and so on.
As for pstn, it consists of a switching plane where mobile switching centers mscs may be found. These functions and interfaces are explained in this chapter. Gsm network structure and network planning contents read. Operator may obtain different network components form different suppliers. This is sometimes also just called the core network.
For e gsm number of arfcns are 174, for dcs1800 arfncs are 374. It has an open, distributed architecture the separation of switching and service control functions full use of ss7 as the signaling infrastructure its clearly defined and specified interfaces the nature of its in structure. The circuit switched network with mscs is called nss network subsystem. Pdf gsm means global system for mobile communication. The gsm network architecture consists of three major subsystems. Gsm network structure and network planning gsm network structure and network planning dipl. The additional components of the gsm architecture comprise of databases and messaging systems functions. Given below is a simple pictorial view of the gsm architecture. If there is a roaming agreement between the home network and one of the mobile networks in the visited country, the call is routed by the visited network towards an international transit network figure 1. Overview of the gsm system and protocol architecture. Um interface the air or radio interface standard that is used for exchanges between a mobile me and a base station bts bsc.
This enables a gsmconnected fax to communicate with any analog fax in the network. History of cellular mobile radio and gsmglobal systems for. Each gsm superframe composed of multiframes either 26 or 51 as described below. Gsm and cdma are competing wireless technologies with gsm enjoying about an 82% market share globally. The gsm frames are grouped together to form multiframes and in this way it is possible to establish a time schedule for their operation and the network can be synchronised. This process is explained clearly with the help of cellular architecture like gsm. A message consisting of a maximum of 160 alphanumeric characters can be sent to or from a mobile station. The cs domain and gsm network of the r99 version do not fundamentally change. Gsm cell structure l the power level of a transmitter within a single cell must be limited to reduce the.
An ms has a number of identities including the international mobile. A gsm modem is a device which can be either a mobile phone or a modem device which can be used to make a computer or any other processor communicate over a network. Network structure the structure of a gsm network the network is structured into a number of discrete sections. It looks similar to pstn but supports an additional service called terminal mobility. This gsm tutorial covers gsm basics, gsm architecture and gsm system features. The purpose of oss is to offer the customer costeffective support for centralized, regional, and local operational and maintenance activities that are required for a gsm network. Topics include bss, mss, bsc, bts, msc, hlr, vlr, auc, eir and more. The international transit network carrier is responsible for the call delivery to the destination network. Explain gsm architecture with a neat block diagram, highlighting all. The ms is the mobile subscriber equipment, which can originate and receive calls and communicate with the bts. As of may 2001, over 550 million people were subscribers to mobile telecommunications. The antenna elevation angle on a number of gsm edge radio access network geran cells has been modified to quantify the impact of this method in a real network.
This type of sim card mobility is analogous to terminal mobility, but provides a personalmobilitylike service within the gsm mobile network refer to chapter 11 for more details. Network operator may equip all there mscs with gateway function or only few. It can be connected to a computer through serial, usb or. Each gsm multiframe composed of frames either 51 or 26 based on multiframe type. Gsm explain gsm architecture with a neat block diagram. Due to the mobility of the subscribers, the organisational structure must be. Muhammad faisal 4 department of computer science, b acha khan university. Gsm provides terminal mobility, with personal mobility provided through the insertion of a subscriber identity module sim into the gsm network mobile station. Gsm or global system for mobile communications is the most popular wireless cellular communication technique, used for public communication. Gsm often described as a true intelligence network, gsm is called the first true wireless network because. Cellular networks khoury college of computer sciences. The hlr is a centralized network database that stores and manages all mobile subscriptions belonging to a specific operator. The mobile station ms the base station subsystem bss the network switching subsystem nss the operation support subsystem oss given below is a simple pictorial view of the gsm architecture. The critical part in the gprs network is the mobile to gsn mssgsn link which includes the msbts, btsbsc, bscsgsn, and the sgsnggsn link.
Cdma network architecture consists of following elements mobile station ms. The cdma network operates in the frequency spectrum of cdma 850 mhz and 1900 mhz while the gsm network operates in the frequency spectrum of gsm 850 mhz and 1900 mhz. An ms consists of the mobile phone itself mobile equipment me and a smart card identifying the subscriber subscriber identity module sim. The base station subsystem the base stations and their controllers.
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