1(a) Explain the concept of frequency reuse. Assume a cellular system of 32 cells with a cell radius of 1.6km, a total spectrum allocation that supports 336 traffic channels, and a reuse pattern of 7. Calculate the total service area covered with this configuration, the number of channels per cell, and a total system capacity. Assume regular hexagonal topology.

1(b) Detail the main factors of change in economics of wireless technology.

2(a) Define Piconet and Scatternet. Explain Bluetooth protocol stack structure.

2(b) Why is the concept of Spread Spectrum important? Briefly explain FHSS and DSSS concept.

3(a) Explain GSM architecture and explain how authentication and encryption is provided in GSM

3(b) Describe the System that uses 802.16 standard and also compare the different 802.16 standards.

4(a) Write short note on Zigbee Architecture

4(b) Explain Hidden and Exposed terminal problem with solution.

4(c) List the 802.11 MAC management functions. Explain in detail Power management function with a neat diagram.

5(a) Define the threats and challenges in wireless systems. Explain the different types of device security issues.

5(b) Neatly explain the WLL Architecture. Explain the two local loop techniques with diagram.

6(a) Mobile IP

6(b) Wireless Sensor Networks

6(c) Handoff strategies

6(d) VPN