Test: Mobile Technologies - 1 - Class 10 MCQ

GSM was the world’s first cellular system to specify digital modulation and level architectures and services. It is the world’s most popular 2G technology. It was developed to solve the fragmentation problems of the first cellular systems in Europe.

In the mid-1980s GSM was called by the name Groupe special mobile. In 1992, GSM changed its name to Global System for Mobile Communication for marketing reasons.

The setting of standards for GSM is under the aegis of the European Technical Standards Institute (ETSI). GSM task was to specify a common mobile communication system for Europe in the 900 MHZ band.

GSM services follow ISDN guidelines and are classified as either teleservices or data services. Teleservices include standard mobile telephony and mobile originated or base originated traffic.

Supplementary ISDN services are digital in nature. They include call diversion, closed user groups, and caller identification, and are not available in analog mobile networks. Supplementary services also include short messaging service (SMS).

SIM (subscriber identity module) is a memory device that stores information such as the subscriber’s identification number, the networks and countries where the subscriber is entitled to service, privacy keys, and other user specific information.

The on the air privacy feature of GSM makes impossible to eavesdrop on a GSM radio transmission. The privacy is made possible by encrypting the digital bit stream sent by a GSM transmitter, according to a specific secret cryptographic key that is known only to the cellular carrier.

The GSM architecture consists of three major interconnected subsystems that interact between themselves and with the users through certain network interfaces. The subsystems are BSS (Base Station Subsystem), NSS (Network and Switching Subsystem) and OSS (Operation Support Subsystem).

First generation cellular system used FDMA/FDD techniques. Second generation standards uses TDMA/FDD and CDMA/FDD multiple access techniques. 2G networks are digital.

Multi-megabit Internet access, communication using Voice over internet Protocol (VoIP), voice activated calls, unparalleled network capacity are some of the characteristics of 3G network. 3G systems promise unparalleled wireless access which is not possible in 2G systems. LTE (Long term Evolution) is a standard of 4G systems.

A suitable cell is a cell on which the UE may camp on to obtain normal service. The UE shall have a valid USIM and such a cell shall fulfil all the following requirements. It provides the best level of service for average subscribers.

GSM (Global System Mobile), IS-136 (Interim Standard 136) and PDC (Pacific Digital Cellular) are the three most popular TDMA standards of second generation. AMPS is a first generation standard.

NSS (Network and Switching Subsystem) manages the switching functions of the system. It allows the MSCs to communicate with other networks such as PSTN and ISDN.

International Telecommunications Union (ITU) used the term IMT-2000 in 1998. It is used for a set of global standards for third generation (3G) mobile telecoms services and equipment.

Wi-Fi stands for Wireless Fidelity.