An 8-User UMTS Channel Unit Processor for 3GPP Base Station Applications

We present a multi-user W-CDMA baseband channel unit processor for cellular base station applications. The ASIC is compliant with the 3GPP/UMTS standard and exceeds 3GPP minimum requirements for high speed data by 1.8 to 6.8dB. It supports up to 8 users simultaneously, with a mix of voice and data services and a maximum uplink data rate of 384kbps. The ASIC implements preamble detection, searching, demodulation with rake-finger processing, channel coding/decoding for voice and data services, and transmission functions. It is coupled to a DSP to form a complete channel element for 8 users. The ASIC has 1.88 million gates plus 2.7Mbits of memory in a 0.16 mum CMOS process operating at 61.44MHz.