A base station for receiving a transmitted signal in a communication system employing CDMA techniques wherein the transmitted signal includes a plurality of short codes, each of which is transmitted repetitively over a fixed period of time and where the received signal has CW interference in addition to the transmitted signal. The base station detects the presence of the short code in a plurality of time phases of the received signal by calculating a likelihood ratio for each phase. The likelihood ratio takes into account the current short code.