Differential space-code modulation for interference suppression

Space-time coding has been receiving much attention recently due to its pot entials offered by fully exploiting the spatial and temporal diversities of multiple transmit and receive antennas, A differential space-time modulati on (DSTM) scheme was recently proposed for demodulation without channel sta te information, which is attractive in fast fading channels where accurate channel estimates are difficult to obtain. However, this technique is sensi tive to interference and is likely to deteriorate or even break down in a w ireless environment, where interference (including intentional and unintent ional jamming) signals exist. We propose a new coding and modulation scheme , referred to as the differential space-code modulation (DSCM), which is in terference resistant, Our focus is on single-user communications, We show t hat DSCM outperforms DSTM significantly when interference is present. This advantage is achieved at the cost of a lower data rate or a wider bandwidth or a combination of both. To alleviate this problem, a high-rate DSCM (HR- DSCM) scheme is also presented, which increases the data rate considerably at the cost of a slightly higher bit-error rate (BER), while still maintain ing the interference suppression capability.