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The correct option is (B) False

For explanation I WOULD SAY: Each of the normal speech frames are grouped into larger structures CALLED multiframes. These multiframes are grouped into superframes and hyperframes.

The CORRECT CHOICE is (a) DTC

The explanation is: DTC (data traffic channel) is the most IMPORTANT data channel as far as the END user is concerned. It carries user information (i.e. speech or user data).

The CORRECT option is (a) Area identification number

Easiest EXPLANATION: For ETACS, area identification numbers (AIDs) are USED instead of SIDs. ETACS subscriber units are able to access any control or VOICE channel in the STANDARD.

The correct choice is (c) PDC

Explanation: PDC (Pacific DIGITAL cellular) is also KNOWN as Japanese Digital Cellular. It was DEVELOPED in 1991 to provide for needed capacity in CONGESTED cellular bands in Japan.

Right choice is (b) Long range telecommunication

The best explanation: DECT provides a CORDLESS communication framework for high traffic DENSITY, short range telecommunications. It COVERS a broad range of APPLICATIONS and environments.

Right choice is (d) DIGITAL European Cordless TELEPHONE

Easy explanation: The Digital European Cordless Telephone (DECT) is a universal cordless telephone standard. It was developed by the European Telecommunications Standard Institute (ETSI).

Correct ANSWER is (a) FCCH and SCH

The best I can explain: FCCH and SCH burst are used to broadcast the FREQUENCY and time synchronization control messages. They are used in TS0 of SPECIFIC frames.

The CORRECT answer is (c) Call diversion

To explain: 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).

The CORRECT choice is (a) RACH

To explain: The RACH (Random Access Channel) is a reverse link channel used by a subscriber unit to ACKNOWLEDGE a page from the PCH. It is also used by MOBILES to ORIGINATE a CALL.

The correct choice is (a) SAT

Easy EXPLANATION: The SAT (supervisory audio tone) has one of the three different frequencies which ALLOW the BASE and mobile to distinguish each other from co channel USERS located in different cells.

Right option is (a) 1.2288 Mchip/s

Best explanation: USER data is spread to a channel chip rate of 1.2288 Mchip/s (a total spreading FACTOR of 128) using a combination of TECHNIQUES. The spreading process is different for the forward and REVERSE links in the original CDMA specification.

Correct choice is (C) Data link control layer

Best explanation: The DLC (data link control) layer is RESPONSIBLE for PROVIDING reliable data links to the network layer. It divides up the logical and physical channels into TIME slots for each user.

Right choice is (C) RAKE RECEIVER

Easiest explanation: At both the base station and the subscriber, RAKE receivers are used to resolve and COMBINE multipath components, thereby reducing the degree of fading. A RAKE receiver EXPLOITS the multipath time DELAYS in a channel and combines the delayed replicas of transmitted signal.

The correct ANSWER is (d) 824-849 MHZ

To explain: IS-95 is specified for reverse link operation in the 824-849 MHz BAND and 869-894 MHz for the forward link. The PCS version of IS-95 has also been designed for international USE in the 1800-2000 MHz BANDS.

The correct OPTION is (d) TCH

The BEST explanation: There are three main control CHANNELS in the GSM system. These are the broadcast CHANNEL (BCH), the common control channel (CCCH) and the dedicated control channel (DCCH). Each control channel consists of several logical channels.

The correct choice is (C) OSS

The EXPLANATION is: The OSS (Operation Support Subsystem) supports the operation and maintenance of GSM. It allows system engineers to monitor, diagnose, and TROUBLESHOOT all aspects of GSM.

Right option is (d) SEVEN

Explanation: The AMPS system uses a seven cell REUSE PATTERN. It also provides sectoring and cell SPLITTING to increase capacity when needed.

The CORRECT choice is (C) OSI

To explain: The DECT system is based on OSI (Open System Interconnection) principles in a MANNER similar to ISDN. A control plane (C-plane) and a user plane (U-plane) use the services provided by the lower layers.

The correct option is (c) IS-95

The best I can EXPLAIN: A US digital cellular SYSTEM based on CDMA was standardized as Interim STANDARD 95 (IS-95). It was standardized by US Telecommunication Industry Association (TIA) and PROMISED increased capacity.

The correct CHOICE is (a) Traffic channels

The explanation is: Traffic channels CARRY digitally encoded user speech or user DATA. It has IDENTICAL functions and formats on both the forward and reverse links.

Right OPTION is (b) NSS

To explain: 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.

Right ANSWER is (a) BSS

To elaborate: The BSS provides and manages radio transmission paths between the MOBILE stations and the Mobile SWITCHING Center (MSC). It also manages the radio interface between the mobile stations and all other SUBSYSTEMS of GSM.

Right choice is (C) D-AMPS

Explanation: USDC (United STATES Digital Cellular System) MAINTAINS compatibility with AMPS in a number of ways. THEREFORE, USDC is also known as D-AMPS (digital AMPS).

The correct OPTION is (a) True

To explain I would say: In each CELLULAR MARKET, the non wireline SERVICE provider (the ‘A’ provider) is assigned an ODD SID (system identification number). The wireline provider (the ‘B’ provider) is assigned an even SID.

The correct option is (b) False

Explanation: In the US AMPS system, there are TWENTY one control CHANNELS for each of the two service providers in each MARKET. However, ETACS supports forty two control channels for a SINGLE provider.

The correct choice is (b) FM, FDD

The explanation: Like all other first generation, analog, CELLULAR systems, AMPS and ETACS use FREQUENCY modulation (FM) and frequency DIVISION duplex (FDD) for radio transmission.

Right ANSWER is (d) Channel

The best explanation: 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).

The correct answer is (d) Packet switched traffic

To explain I would say: 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.

The correct choice is (d) PCH

Explanation: The PCH provides paging signals from the BASE STATION to all mobiles in the cell. It notifies a specific MOBILE of an INCOMING call which originates from the PSTN.

Right option is (c) DCCH

For EXPLANATION: CCCH CONSISTS of THREE different channels. They are paging channel (PCH), which is a forward link channel, the random access channel (RACH) which is a reverse link channel, and the access GRANT channel (AGCH) which is a forward link channel.

Correct choice is (a) True

Easy explanation: The MAIN function of DECT is to provide LOCAL mobility to PORTABLE users in an in-building Private Branch Exchange (PBX). It provides EXCELLENT quality and services for voice and data APPLICATIONS.

Right CHOICE is (c) RADIO FIXED Part

The best explanation: RFP (Radio Fixed Part) SUPPORTS the physical layer of the DECT common air interface. Every RFP covers one cell in the microcellular system. A full duplex operation is achieved using TDD.

Right OPTION is (a) 1.25 MHZ

To explain I WOULD say: To facilitate graceful transition from AMPS to CDMA, each IS-95 channel occupies 1.25 MHz of SPECTRUM on each one way link, or 10% of the available cellular spectrum for a US cellular provider.

The correct option is (c) SIM

Easiest EXPLANATION: 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.

Correct choice is (a) GSM

The BEST I can explain: 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.

Correct answer is (b) NADC

The best explanation: USDC is also known as North American Digital Cellular (NADC). It has been INSTALLED in North America in the countries LIKE CANADA and MEXICO.

Right answer is (b) False

Explanation: AMPS and ETACS use different physical rate channels for transmission of voice and CONTROL channels. A control CHANNEL is used by each base station in the system to simultaneously PAGE subscriber units to ALERT them of incoming CALLS.

Right ANSWER is (d) MAC layer

For explanation: The MAC (Medium Access Control) layer consists of a PAGING channel and a control channel for the transfer of signalling INFORMATION to the C-plane. The U-plane is SERVED with channels for the transfer of user information.

Right ANSWER is (c) ETSI

To elaborate: 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.

The CORRECT answer is (B) Groupe special mobile

To explain: 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 CORRECT ANSWER is (a) Analog MOBILE Phone SYSTEM

The explanation: AMPS stands for Analog Mobile Phone System. It was first deployed in late 1983 in urban and suburban areas of CHICAGO by Ameritech.

The correct option is (c) SACCH

The explanation: The SACCH (slow associated control channel) is sent in EVERY time slot and provides a signalling channel in parallel with the digital speech. The SACCH carries various control and supervisory messages between the SUBSCRIBER UNIT and the BASE station.

Correct answer is (b) CONTROL CHANNELS

To explain: Control channels carry signalling and synchronizing commands between the BASE station and mobile station. CERTAIN types of control channels are defined for just the forward or reverse link.

The correct answer is (a) ETACS

To ELABORATE: ETACS is VIRTUALLY identical to AMPS. It was developed in MIDDLE 1980S and stands for European Total Access Communication System.