FEEDFORWARD NOISE CANCELER FOR PR1ML

We present the performance of a feedforward noise canceller (FNC) for the PR1 [(1+D)] channel combined with an 8/10 DC free code. It appears the PR1 channel can be superior to PR4 [(1-D)(1+D)] and EPR4 [(1-D)(1 +D)(2)] for high density magnetic recording due to a characteristic of high frequency suppression. Simulation results show that PR1 with FNC is better than EPR4 for K greater than or equal to 2.5 [K=PW50/T]. We adapted PR1 with FNC into an actual DDS3 (Digital Data Storage 3) sys tem and we got an improved result. Applying FNC to DDS3 system can imp rove the error rate by around 10(2).