1. Consider the uplink of an IS-95 system.
a. A single cell is modeled as a disk of radius 1 km. If a mobile at the edge of the cell transmits at its maximum power limit, its received SNR at the base-station is 15 dB when no one else is transmitting. Estimate (via numerical simulations) the average sum capacity of the uplink with 16 users that are independently and uniformly located in the disk. Compare this to the corresponding average total throughput in a system with conventional CDMA decoding and each user perfectly power controlled at the base-station. What is the potential percentage gain in spectral efficiency by using the more sophisticated receiver? You can assume that all mobiles have the same transmit power constraint and the path loss (power)
attenuation is proportional to r-4 .
b. Part (1) ignores out-of-cell interference. With out-of-cell interference taken into consideration, the received SINR of the cell edge user is only -10 dB. Redo part (1). Is the potential gain from using a more sophisticated receiver still as impressive?