On the symbol timing recovery in space-time coding systems

Space-time coding has received considerable interest recently as a simple transmit diversity technique for improving the capacity and data rate of a channel without bandwidth expansion. Most research work in space-time coding, however, assumed that the symbol timing at the receiver is perfectly known. In practice, this has to be estimated with high accuracy. In this paper, two symbol timing recovery algorithms for space-time coding systems are proposed. The first one is based on orthogonal training sequences and approximated log likelihood function. It is an improvement of a previous symbol timing synchronization algorithm in that high estimation accuracy can be achieved even when the over sampling factor is small. The second one employs the squaring algorithm. It offers good performance and does not require training sequences.