Johannes W. M. Bergmans

Dual decision feedback equalizer

The detector of Dahlman and Gudmundson (1988) ranks among the simplest known extensions of the decision feedback equalizer (DFE). The article develops a simplification of this detector, and evaluates its performance vis-a-vis other near maximum likelihood detectors. Comparable performances are observed at much lower complexity levels.

On the SNR merits of run-length-limited codes in feedback-equalized recording systems

An upper bound is derived for the SNR merits that may be attributed to run-length-limited codes when used in high-density recording systems with optimum mean-square decision feedback equalization. It is argued and exemplified that these merits often lag behind the SNR improvement that uncoded storage would bring about via a reduction of the signaling rate. Losses are quantified for a number of practical codes as well as for maxentropic (d,k) sequences. >