On the Performance of Spatial Modulation OFDM

In this paper a novel multiple antenna transmission technique, named spatial modulation (SM) is proposed. Here SM is applied to OFDM (orthogonal frequency division multiplexing) transmission. In SM the transmit antenna number is used as an explicit source of information. SM maps a block of information bits to an information symbol and to a particular transmit antenna such that the same information symbol transmitted from different antennas conveys different information. At each time instant, only the corresponding transmit antenna will be radiating signal power on a particular OFDM sub-carrier, while all other transmit antennas transmit zero power. Consequently, inter-channel interference (ICI) at the receiver input and the need for antenna synchronization are completely avoided. A comparative analysis is made on the performance of SM and V-BLAST (Vertical Bell Labs Layered Space-Time) algorithm assuming Rician fading channel, spatial correlation (SC) and mutual coupling (MC). It is shown that at a BER (bit error ratio) of 10^-3, SM outperforms V-BLAST by 5 dB in the presence of Rician fading and by 7 dB in the presence of spatial correlation and mutual coupling for 6 bits/symbol/sub-carrier transmission.