Macrodiversity in DS/CDMA asynchronous systems with decorrelating detectors

This paper analyzes the application of macrodiversity in Code Division Multiple Access (CDMA) asynchronous systems with decorrelating detection in the reverse link. It is shown that decorrelating detectors allow predetection combining and, utilizing this property, several combining strategies are studied. We obtain the set of combining factors which minimize the bit error probability, and based on these results, we propose the Simplified Minimum Error Criterion (SMEC), which has little impact on the overall complexity of the system and outperforms the Maximal Signal to Interference plus Noise Ratio Combiner (MSINRC). Using this technique, it is possible to perform a distributed detection in the area influenced by the mobile, allowing the coexistence of heterogeneous cells and the effective use of microcells.