Performance of combined diversity and spatial multiplexing techniques over space

The space-time coding can provide a diversity gain for the multiple-antenna system while spatial multiplexing provides higher data rates. In this paper we are combining space-time block code (STBC) with spatial multiplexing technique over space to take advantages of both schemes. The transmit antennas are divided into groups, with one of the groups transmitting STBC code given by Alamouti and other transmits spatial multiplexing data. At the receiver, a minimum mean square error (MMSE) detector with interference cancelation (IC) is integrated with the space-time decoder to reconstruct the desired signal effectively. MMSE decoder is used for compared to only MMSE method. STBC coded symbols (estimation of interfering terms and then space-time decoder is applied. 4×1 system gives slightly higher diversity gain with rate=3 as s1s2) are giving 8 dB gain as compared to purely orthogonal code (2×1 MMSE-SIC). Rate of 3×1 system is less but it is performing better in terms of reliability as compared to 4×1 system.