A cellular service provider decides to reuse the frequency in a system which can tolerate a signal-to- interference ratio of 15 dB. Assume a path loss exponent of v = 4. (i) Find the optimal value of cluster size N for (a) omnidirectional antennas, (b) 120 sectoring, and (c) 60 sectoring. (6 points) (ii) Should sectoring be used? If so, which case (120 or 609) should be used? Answer with valid reason. (3 points) (hint: consider trunking efficiency.) (iii) Now assume there are 54 traffic channels in the network. Cluster size N=3 is used. If each user generates 0.5 call per hour on average, and holds the channel for an average duration of 3 minutes, determine how many users each cell can support for 5% call blocking probability with (a) omnidirectional antennas, (b) 120 sectoring, and (c) 60 sectoring. (9 points) A cellular service provider decides to reuse the frequency in a system which can tolerate a signal-to- interference ratio of 15 dB. Assume a path loss exponent of v = 4. (i) Find the optimal value of cluster size N for (a) omnidirectional antennas, (b) 120 sectoring, and (c) 60 sectoring. (6 points) (ii) Should sectoring be used? If so, which case (120 or 609) should be used? Answer with valid reason. (3 points) (hint: consider trunking efficiency.) (iii) Now assume there are 54 traffic channels in the network. Cluster size N=3 is used. If each user generates 0.5 call per hour on average, and holds the channel for an average duration of 3 minutes, determine how many users each cell can support for 5% call blocking probability with (a) omnidirectional antennas, (b) 120 sectoring, and (c) 60 sectoring. (9 points)