A Method for Evaluating Minimum Free Chernov Distance of Trellis-Codes for Discrete Memoryless Channel

In this paper, we present a method for evaluating the minimum free Chernov distance of trellis-codes for a discrete memoryless channels(DMC). In order to design an e cient trellis-code for the DMC, we need to evaluate the minimum free Chernov distance of the target code. However, the lack of the additive property of the Chernov distance prevents a conventional branch-and-bound search for evaluating the minimum distance. To overcome the di culty, we present a lower bound on the Chernov distance with an additive property. The lower bound plays a key role in the minimum distance evaluation algorithm presented here. By using the proposed algorithm, we have derived the minimum free Chernov distance of some binary linear convolutional codes over Z-channel. key words: Chernov distance, discrete memoryless channel, trellis-code, minimum free distance