Performance Comparison of Iterative Multiuser Detection Techniques In Interference Limited Cellular Networks

This paper deals with the iterative multiuser detection for in an uplink-OFDM system employing parallel concatenated convolution codes (pccc) with gray mapping. Joint multi-user detection is made possible through cooperation between different access point and joint detection at a single central point. Since higher order modulation is being used, to reduce complexity, the number of incoming data streams are decoupled through a linear prefilter. This is followed by either simple bit-interleaved coded modulation (BICM) or a BICM with turbo detection. The decision feedback among different users can follow subsequently at the end of each stage either sequentially (SIC) or in parallel (PIC). The resulting frame error rate curves are plotted as a function of average SNR and compared against the performance of genie PIC. It is shown that the estimates obtained through V-BLAST with turbo iterations are more reliable resulting in considerable performance gains over PIC based techniques. The performance of the most promising receiver is also investigated for different positions of the user equipment in different cells, and results in a considerable improvement in performance at the cell edge