The capacities of ALOHA and power-controlled CDMA in the UMTS downlink channel

F. Borgonovo, A. Capone, M. Cesana, L. Fratta
The 5th International Symposium on Wireless Personal Multimedia Communications  
In this paper we compare the pe$ormance of data transmission on the downlink channel of a cellular system when two different interference-reducing techniques are used. The first is the conventional CDMA with closed loop power control with FEC coding and the second is S-ALOHA. In the latter, packets are transmitted in random slots at the fill channel rate, therefore using bandwidth to achieve a random time spreading of packets. Both techniques use retransmissions when error occurs. The
more » ... evaluation is obtained by simulation in order to consider a realistic cellular environment that takes into account the bursty nature of the inter-ceil interference noise and its real statistics, which, in the S-ALOHA case where no spreading is used, is far from being normally distributed. The results presented in the paper show that the S-ALOHA approach, in the UMTS environment here considered, achieves better bandwidth eficiency than CDMA.
doi:10.1109/wpmc.2002.1088199 fatcat:2gqhgmzjjvdx5lpopx5lrt34pi