Performance evaluation of double space-time transmit diversity with joint channel estimation and decoding over rayleigh flat fading channel

Abstract

An architecture that theoretically obtains channel capacity on Multi-Input Multi-Output (MIMO) systems was proposed as BLAST in [10] and Space-Time Block Codes (STBC) which achieves the diversity gain from the transmit diversity was exploited in [5] and [6]. However, we can not get the both sides of data reliability and data throughput at the same time because the transmit diversity comes at the cost of throughput and vice versa. At this point of view, in MIMO wireless communications, Double Space-Time Transmit Diversity (DSTTD) is a good communication scheme which compromises between the BLAST and STBC. It offers a very effective tradeoff between diversity and Spatial Multiplexing (SM). We show that DSTTD can be efficiently recovered using joint Maximum-Likelihood (ML) and Minimum Mean Squared Error (MMSE) interference cancelation technique. However, most of the previous works assumed that the receiver knew the channel information perfectly. In real wireless communications, receiver never knows the Channel State Information (CSI). Clearly, the method to estimate the channel accurately is one of the key techniques to improve the performance in wireless communications. In [9], authors propose the MIMO channel estimation technique which uses the pilot sequences in the transmit signals to estimate the channel fading coefficients. We confirm that this channel estimation method is effective in STBC scheme. However, the more the number of transmit antennas is increased, the more training sequences periods are needed in this estimation method. Recently, unlike a conventional channel estimation, iterative receivers for MIMO wireless links, which perform joint channel estimation and decoding, have received great attention due to their performance gain achieved. They send the training sequences and compute the channel coeffcients by adaptive filter. We apply the joint channel estimation and decoding to the DSTTD system and get the following results. Firstly, We show that...