1. (20 points) A cellular service provider decides to use digital TDMA scheme which can tolerate a signal-to-interference ratio (SIR) of 15 dB in the worst case. Assume that all co-channel

BSs are equal distant from the mobile, i.e., Di-D. Also assume a path loss exponent of n=4. Find the optimal value of N for a) Omnidirectional antennas b) 120 degree sectoring antennas c) 60 degree sectoring antennas. Should sectoring be used. If so, which case, 60 degree or 120 degree, should be used? Hint: Consider trunking efficiency in your decision.