Efficient algorithms for space-time multiuser detection

This paper presents a new algorithm of blind adaptive space-time multiuser detection for synchronous CDMA systems with antenna arrays. In contrast to previously reported spatial diversity detectors which use the decorrelating or minimum mean square (MMSE) detector for each receiving antenna, our algorithms employ the known signature waveform to estimate the combining vector for the desired user. Therefore, we only need to resolve the decorrelating detector or MMSE detector once by combining the array outputs with estimated combining vector. The new algorithm can provide the same performance improvement as that offered by the conventional spatial diversity multiuser detectors with significant savings on computational complexity