Statistical Time Channel Evaluation of Array Codes in Block Coded Phase

Statistical Time Channel Evaluation (STCE) is the process of measuring communication channels and of employing the data obtained to describe those channels and hence their relative capabilities for passing communications traffic. In this paper, a simple low complexity technique of STCE that employs the trellis structure of array codes in Block Coded Modulation (BCM) is proposed for Additive White Gaussian Channel (AWGN). It is shown that the STCE technique gives a more reliable estimation under low noise conditions than at high noise conditions. Also, the STCE of 8PSK is shown to be less reliable at high Eb/No than that of QPSK. This is due to the wider range of the code metric at specific Eb/No for the higher order modulation as compared to those of lower modulation schemes. Array codes having smaller block length give better throughputs under very high noise conditions whereas those with longer block length give suitable throughput under lower noise conditions. Such a technique can be incorporated into adaptive coding schemes in order to improve the reliability and throughput of the codes in time varying channels.