Wireless Communications

(d) Compare & contrast. FDD & TDD. Where will you prefer TDD & why. 

Explain with a neat B.D the GSM system Architecture emphasizing on the interfaces, frame structure, logical channel & Diversity scheme adopted. 

(a) How RAKE Reception enables path diversity in CDMA. Discuss the principle behind it. 

(b) Explain with a neatly labelled B.D. the FC & RC structure of IS-95 CDMA & establish the roles of PN& Welsh codes employed therein.

(a) What is EDGE & which generation does it belong. Explain how EDGE achieves greater data rates than allowed in GSM. 

(b) Write down the GPRS Architecture & explain its key features.

(a) Compare & control WCDMA & Cdma-2000 schemes under IMT-2000.

(b) Explain briefly the Bluetooth Architecture, Radio Link & Protocol Stack. 

(a) What is DCT? List the PHY interface it operates on along with its radio spectrum.

(b) Compare Rayleigh & Ricean fading & highlight their key differences

 (c) How is IS-136 different from GSM? List the prime differences.

(b) List the wireless channel types in terms of frequency selectivity & time delay. What are fast fading & flat channels?

(e) List the data rate for HSPA, HSPAT & Wi-fi. Compare these to transmission speed of Wi-max. 

(a) Compare & contrast FDMA, TDMA & CDMA. Why is CDMA said to have a soft capcity.

(b) What are Soft Handoffs.

(c) Discuss the Near-Far Effect in CDMA & Ways to alleviate it. 

Write short note on:-

(a) Diversity Gain

Write short note on:-

(b) Frequency Reuse & Cellular Topology

Write short note on:-

c) WLAN 802.11 PHY Layer

Write short note on:-

(d) Mobile Satellite Systems

Write short note on:-

(e) Adhoc Mobile Netoworks

b. Explain GSM intra BSC handover operation with a figure. 

b. Explain the characteristics of 2G and 3G cellular systems.

a. Explain the generation of MSISDN, IMSI and IMEI.

b. Explain the function of HLR and ILR.

c. Explain a mobile originated call in a cellular network with a neat flow diagram.

a. A service provider is given license for total bandwidth of 5 MHz and each system subscriber roquires 10 kHz bandwidth. Determine the system capacity if the service provider implements a cellular system with 35 transmitter sites and cluster size of 7. 

b. Determine frequency reuse distance for a cluster size of 7 and a cell radius of 6 km.

c. Explain mobility management concept. Explain the functions of location management with a figure. 

a. Explain the GSM signaling model.

b. Explain the steps in call setup in GSM using mobile station roaming number.

a.  List out the ten operations in call setup in GSM system. Explain in detail ciphering mode setting and IMEI check. 

a. Explain the various steps in AMPS mobile terminated call.

a. Explain the functions of three layers in a network management system.

b. Explain the generation of CDMA paging channel.

a. Explain the path loss model for free space propagation.

b. What is the received power in dBm for a signal in free space with a transmitting power of 1 kW, frequency of 1800 MHz and distance from the receiver of 2000 meters if the transmitting antenna and receiving antennas have a gain of 1.6? What is the path loss in dB? 

c. Explain frequency hopping and direct sequence spread spectrum techniques.

a. Discuss the design issues of IEEE 802.11 and explain the working of BSS, DS and ESS network

b. Explain the details of Bluetooth protocol stack with a figure.

What is meant by different Generation of Wireless Networks? When do we conclude that the Generation has changed?

Compare the various Generations of Wireless Networks & their types w.r.t. Mobility, Range, Speed of Transmission Radio spectrum used. 

(a) Show that the processing Gain (PG) achieved by the spreading-Dispreading action in Spread spectrum equals the chip sequence length.