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The correct choice is (a) 10^-3

The explanation: Bluetooth has a BIT error RATE (BER) of 10^-3. Bluetooth uses a number of forward error control (FEC) coding and AUTOMATIC repeat REQUEST (ARR) schemes to achieve this bit rate.

Correct choice is (d) 1 Mbps

The BEST explanation: Each user in BLUETOOTH uses a radio channel symbol RATE of 1 Mbps using GFSK modulation. The frequency hopping SCHEME of each Bluetooth user is determined from a cyclic code with a length of 10^27-1.

Right choice is (d) 2.4 GHz ISM Band

Easy explanation: Bluetooth is a radio technology operating in 2.4 GHz FREQUENCY band. Bluetooth is BEST suited for low-bandwidth applications LIKE TRANSFERRING sound data with telephones (i.e. with a Bluetooth headset) or byte data with hand-held computers (transferring files) or KEYBOARD.

Right answer is (b) Wireless Internet Service Provider

For explanation I would SAY: WISP is wireless Internet Service Provider used to explore public LANs (publican). It builds a nationwide INFRASTRUCTURE of WLAN access points in selected hotels, RESTAURANTS or AIRPORTS. It then charges a monthly subscription fee to USERS who wish to have always on Internet access in those selected locations.

The correct option is (b) False

The explanation: CDMA2000 works in both FDD and TDD mode. Cdma2000 developed for WIDE AREA cellular coverage uses FDD. And TDD is USED by Cdma2000 for indoor cordless type applications.

Correct choice is (b) Wireless Local Area Network

For EXPLANATION I would say: WLAN stands for Wireless Local Area Network. Wireless NETWORKS is increasingly USED as a replacement for WIRES within homes, BUILDINGS, and office settings through the deployment of wireless local area networks (WLANs).

The correct ANSWER is (C) IS-95B

The explanation: IS-95B (Interim Standard 95B) is code division MULTIPLE access standard for 2.5G. It is an upgradation of IS- 95 which is a second generation standard of CDMA.

Right choice is (B) Cdma2000 1xEV-DO, Cdma2000 1xEV-DV

To elaborate: Cdma2000 1xEV is an EVOLUTIONARY upgrade for Cdma2000. It PROVIDES two options, for ACCESSING only data (Cdma2000 1xEV-DO) and for both data & voice (Cdma2000 1xEV-DV).

Correct OPTION is (d) IEEE 802.11g

Best explanation: IEEE 802.11g is developing CCK-OFDM (Complementary Code Keying ORTHOGONAL Frequency DIVISION Multiplexing) standards. It will support roaming CAPABILITIES and dual band use for public WLAN networks. It also has backward compatibility with 802.11b technologies.

Right option is (a) Project based on W-CDMA

For explanation I would say: 3GPP is a 3G Partnership Project for WIDEBAND CDMA standards based on backward compatibility with GSM and IS-136. The project was established in December 1998. Its initial scope was to make a GLOBALLY applicable third generation mobile phone SYSTEM.

Correct option is (b) False

To explain: WLANs USE low power and generally do not require a license for SPECTRUM. They provide ad hoc high data transmission rate connections deployed by INDIVIDUALS. In the late 1980s, FCC provided licence free bands for low power spread spectrum DEVICES in ISM band, which is used by WLAN.

Right choice is (a) CDMA

To elaborate: Although UMTS is DESIGNED to operate on EVOLVED GSM core networks, it uses code division multiple access (CDMA) for its air interface. The majority of the 3G systems in operation employ CDMA, while the rest USE TDMA. CDMA allows various users to share a channel at the same time, while TDMA allows users to share the same channel by CHOPPING it into different time SLOTS.

The CORRECT answer is (b) 200 KHz

To ELABORATE: The GLOBAL System for Mobile (GSM) uses a carrier SEPARATION of 200 KHz, each CHANNEL supporting upto eight users.

The correct answer is (c) Cdma2000 1xRTT

To explain: Cdma2000 1xRTT is the first 3G air interface. Here, RTT stands for Radio Transmission TECHNOLOGY and 1x indicates that the bandwidth is one TIMES that of the ORIGINAL CDMAONE channel. It is modulated on a single CARRIER.

Right CHOICE is (B) TWICE

To elaborate: CDMA2000 support up to twice as many users as the 2G CDMA standard. It also provides the two times the standby time for longer lasting battery LIFE.

Correct answer is (c) UMTS

For explanation I would SAY: Japan uses UMTS (W-CDMA) standard for its 3G network. The standards used are UMTS 800, UMTS 900, UMTS 1500, UMTS 1700 and UMTS 2100. They are STANDARDIZED by ARIB (Association of RADIO industries and Business).

Correct option is (d) GSM

Easiest explanation: GSM (Global System for Mobile) is a TDMA STANDARD for 2G network. HSCSD (High Speed Circuit Switched Data), GPRS (General PACKET Radio Service) and EDGE (Enhanced Data rates for GSM Evolution) are TDMA standards of 2.5G technology.

The correct answer is (a) Wireless Application PROTOCOL

To explain: 2.5G technology supports a new web browsing format LANGUAGE, which is called Wireless Application Protocol (WAP). It allows standard web pages to be viewed in a COMPRESSED format specifically designed for small, PORTABLE hand held wireless devices.

Correct choice is (d) New packet OVERLAY including routers and gateways

The best I can explain: GPRS requires a GSM operator to install new routers and Internet gateways at the BASE station along with new SOFTWARE upgrade. New base station RF hardware is not REQUIRED.

Correct option is (c) IS-95

The explanation is: UMTS assures backward compatibility with the SECOND GENERATION GSM, IS-136 and PDC TDMA TECHNOLOGIES. It is also compatible with all 2.5G TDMA techniques like GPRS and EDGE. But it does not provide compatibility to CDMA technologies of 2G and 2.5 G. IS-95 is a CDMA standard of 2G.

The correct choice is (b) 625 microseconds

For explanation: Bluetooth USES a timeslot of 625 microseconds. A data channel hops randomly 1600 TIMES PER second between 79 RF channels. Thus, each channel is divided into TIME slots 625 microseconds.

Correct choice is (a) W-CDMA

The explanation is: The 3G EVOLUTION for GSM, IS-136 and PDC systems LEADS to W-CDMA (WIDEBAND CDMA). It is based on the network fundamentals of GSM, as well as merged versions of GSM and IS-136 through EDGE. GPRS, EDGE and HSCSD are 2.5G networks.

The correct choice is (b) 8- PSK

Easiest explanation: EDGE uses a new digital modulation FORMAT, 8- PSK (Octal Phase Shift Keying). It is used in addition to GSM’s STANDARD GMSK (GAUSSIAN Minimum Shift Keying) modulation.

Right choice is (a) π/4 DQPSK

For EXPLANATION: IS-136 USES π/4 DQPSK modulation technique. This technique allows a BIT rate of 48.6 Kbit/s with 30 KHz CHANNEL spacing which gives a bandwidth EFFICIENCY of 1.62 bit/s/Hz.

Right choice is (c) King HERALD Bluetooth

The explanation is: Bluetooth standard is named after King HARALD Bluetooth. He was the 10th century Viking who united Denmark and Norway. The Bluetooth standard aims to unify the connectivity chores of appliances within the PERSONAL workspace of an INDIVIDUAL.

Right answer is (a) True

Explanation: Cdma2000 does not REQUIRE change in entire base station or additional RF equipment. All the CHANGES are made in software or in BASEBAND HARDWARE.

Correct choice is (a) IMT 2000

To ELABORATE: 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.

The correct choice is (b) BPSK

To ELABORATE: IS- 95 uses BPSK (Binary Phase Shift KEYING) with quadrature SPREADING. It is regarded as one of the most robust digital MODULATION technique and is used for long distance wireless COMMUNICATION.

The CORRECT answer is (b) TDMA/FDD and CDMA/FDD

To explain: First generation cellular system used FDMA/FDD techniques. SECOND generation STANDARDS uses TDMA/FDD and CDMA/FDD multiple access techniques. 2G networks are digital.

The correct option is (a) 10 Mbps

Explanation: HomeRF 2.0 has DATA rate of the ORDER of 10 Mbps. The FHSS proponents of IEEE 802.11 have formed the HomeRF STANDARD that supports the frequency hopping EQUIPMENT. In 2001, HomeRF developed a 10 Mbps FHSS standard called HomeRF 2.0.

Correct ANSWER is (b) 3.84 MCPS

The explanation is: W-CDMA USES a chip rate of 3.84 Mcps. Chip rate is the product of symbol rate and spreading factor. If the symbol rate is 960 KBPS and spreading factor is 4 for W-CDMA, then the chip rate is 3.84 Mcps. The chip rate for CDMA2000 and GSM are 1.2288 Mcps and 27.0833 Ksps respectively.

Right answer is (a) GMSK

Best EXPLANATION: GSM uses a form of modulation known as GMSK (GAUSSIAN Minimum SHIFT Keying). It is a form of modulation with no phase DISCONTINUITIES and provides data transmission with efficient SPECTRUM usage.

Right choice is (a) CDMAONE

To EXPLAIN: The POPULAR 2G CDMA standard, Interim Standard (IS-95) is also known as CdmaOne. The 2.5G CDMA standard, IS-95B is called CdmaTwo. And IS-136 is a TDMA standard for 2G.

Correct option is (c) AMPS

Explanation: 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.

Correct answer is (b) By ALLOWING single user to USE consecutive user time slots

The best I can explain: HSCSD allows individual data users to use consecutive time slots in order to obtain HIGHER speed data access on the GSM network. In case of GSM, it limits each user to use only one specific time slot.

The correct option is (d) HIPERLAN/2

The explanation is: HIPERLAN/2 has emerged as the next generation European WLAN STANDARD. It provides UPTO 54 Mbps of user DATA to a variety of NETWORKS. The networks includes the ATM backbone, IP BASED networks and the UMTS network.

The correct answer is (a) FHSS and DSSS

To ELABORATE: ORIGINAL IEEE 802.11 used both the approaches of FHSS (Frequency Hopping Spread Spectrum) and DSSS (Direct SEQUENCE Spread Spectrum). But from LATE 2001s, only DSSS modems are used within IEEE 802.11.

Correct choice is (a) Modulation and coding schemes

Easiest explanation: EDGE allows nine different AIR INTERFACE formats known as multiple modulation and coding schemes (MCS). Each MCS state may use either GMSK or 8- PSK modulation for network access, DEPENDING upon the instantaneous demands of the network and the operating conditions.

Right option is (c) GSM and IS-136 both

Easiest explanation: GPRS (GENERAL Packet RADIO Service) network provides a packet network on dedicated GSM or IS-136 radio channels. EDGE (Enhanced Data rates for GSM Evolution) is also developed KEEPING in desire both GSM and IS-136 operators.

Correct option is (c) GFSK

The BEST explanation: BLUETOOTH uses GFSK (Gaussian Frequency Shift KEYING). When GFSK is used for Bluetooth modulation, the frequency of the carrier is SHIFTED to carry the modulation. By doing this the Bluetooth modulation achieves a bandwidth of 1 MHz with stringent filter requirements to prevent interference on other channels.

Right choice is (b) False

The explanation: As, WLAN could be used to provide access for the last 100 meters into HOMES and BUSINESSES. Therefore, the price of WLAN hardware is far below 3G telephones and fixed WIRELESS equipment.

Correct ANSWER is (a) True

For explanation: W-CDMA is designed to PROVIDE backward compatibility and INTEROPERABILITY for all GSM, IS-136/PDC, GPRS and EDGE EQUIPMENT. But due to a wider AIR interface bandwidth of W-CDMA, it requires a complete change of RF-equipment at each base station.

The correct choice is (c) EGPRS

For explanation: EDGE is sometimes also referred as Enhanced GPRS (EGPRS). It is an enhancement of a GSM NETWORK in which EDGE is introduced on top of the General Packet Radio Service (GPRS). It is used to transfer DATA in a packet switched mode on various time slots.