Cellular CDMA systems employ soft handover for both coverage and link reliability. A mobile receiver within an IS-95 system has been communicating for a while and receives the pilot signals shown in...

Cellular CDMA systems employ soft handover for both coverage and link reliability. A mobile receiver within an IS-95 system has been communicating for a while and receives the pilot signals shown in Figure 8.19. We assume that this mobile receiver is in soft handover and your task is to identify the set of cells that are in the active set of the mobile unit at time τ = τ0. The handover drop time is 10 seconds and the handshaking time between the base station and the mobile can be neglected. a) Going through each pilot signal, identify the status (in the active set, candidate set or neighbor set) of each pilot signal at time τ0. Clearly explain your results. b) Deduce the set of cells that are in the active set of the mobile unit at time τ0.

Q5!:

A wireless terminal consumes 2 W circuit power in transmission mode. In sleep mode, it consumes 0.5 W circuit power. It needs to send 100 bits in the buffer over an AWGN channel once every T seconds. After sending all bits, it goes to sleep mode to save power. Assume the transitions between different modes are instantaneous. All other parameters, if not specified, are assumed to have a value of 1. How fast, in terms of both data rate and time, should the terminal send the bits?