A complexity cost function for a network of WCDMA basestations using software defined radio with multi-user detection

This paper determines a cost function for a network of WCDMA-FDD base transceiver station´s (BTS) for the purpose of dimensioning a software defined radio (SDR) implementation. This cost function allows for both a conventional direct-sequence spread spectrum receiver and one that uses a multi-user detector (MUD). An SDR architecture is proposed and the cost function is expressed in terms of cell diameter and signal processing load. The cost function is developed in terms of a large number of system parameters including the cost of using spectrum. Based on certain assumptions and by implementing MUD receivers it is shown that the network cost can be reduced when cell size must be maintained above a minimum figure, i.e. base station sites are limited.