Recent trends in multiuser detection techniques for SDMA–OFDM communication system

The space division multiple access–orthogonal frequency division multiplexing (SDMA–OFDM) technique is emerged as a most competitive technology for future wireless communication system as it can provide high spectral efficiency and resistance from inter symbol interference (ISI). The SDMA like multiple access techniques are prone to multiple access interference (MAI) because multiple users transmit their data simultaneously. Such a receiver requires appropriate multiuser detection (MUD) scheme to detect individual user’s signals correctly by mitigating MAI. Further, due to non-linear behaviour of wireless channel, the signals at SDMA receiver often become linearly non-separable. As a result, MUD becomes a challenging multidimensional optimization problem. Considering these challenges, this paper reviews various MUD techniques for SDMA–OFDM system.