Evaluation of hybrid error control systems

In the paper, the performances of hybrid as well as of ARQ and FEC systems are evaluated by simulation generating error statistics corresponding to a case of data transmission over local switched telephone lines. The channel model was based on finite time renewal processes. The criteria for a hybrid system with convolution codes were specially developed. The results show that, for simulated channel, characterised by dense bursts and many random errors in between, hybrid systems based on convolutional codes can improve the reliability considerably.