A UMTS network consists of two cells. There are six active terminals in the network. The channel gains between every terminal and both base stations are given in Table 7.3. The table also shows the supported data rate for each terminal in both uplink and
downlink. The chip rate is 3.84 Mchip/s. Every terminal is assigned to the base station which has the better channel gain. The target Eb/N0 is 8.5 dB for all terminals in both UL and DL. Assume the worst-case scenario for the orthogonality and voice activity factor. The maximum available power at the base stations is 5 W. The maximum allowed throughput of the cell is 2 Mb/s. The maximum transmit power of terminals is 23 dBm. Finally, the additive noise power in UL and DL is 90 dBm
(a) Calculate the optimum transmit DL and UL power values.
(b) Is the system feasible (in UL and DL)? If not relax the network using the optimum removal algorithm. (c) Calculate the UL and DL load factors.
(d) Calculate the UL noise rise.
(e) If the threshold value for both UL and DL load factors is 0.8, calculate the maximum possible acceptance of new terminals similar to terminal number 1 in Table 7.3.
(f) If terminal 2 requests a new service that requires increasing the UL data rate from 16 kb/s to 64 kb/s, will the AC accept this request?
(g) Explain the network behaviour if the channel gain of terminal 4 with base station 1 has decreased according to the shadowing effect = 120 dB.