Abstract
A method to construct trellis codes matched to class-4 partial response (PR4) and exteded class-4 partial response (EPR4) channels is studied. This coding method is based on the technique of set partitioning. In our method, all allowable output symbols from a partial response channel are defined as a signal constellation in Euclidean space and each subset decomposition of defined signal constellation is adopted in a multidimensional Euclidean space. Using this code construction technique, we can find optimal trellis coding and analyze a code structure easily and effectively. As a result of this coding technique, it is shown that the rate 9/10 trellis codes with a constraint length of 6 or 7 can provide about 2.4,2.3dB advantage over the conventional rate 8/9 (0,4/4) code in a PR4ML and 16/17 (0,6/6) code in an EPR4ML equalizations at a bit error rate of 10^<-4>, respectively.
