Showing papers on "Precoding published in 1988"

On saving decoder states for some trellis codes and partial response channels

Abstract: It is shown that under certain conditions, when convolutional codes with precoding are used in conjunction with a partial response channel, the number of decoder states in a maximum-likelihood decoder matched to both the code and channel is 1/2 of that predicted by J.K. Wolf and G. Ungerboeck (ibid., vol.COM-34, no.7, p.751-72, 1986). >

Digital communication system using partial response and bipolar coding techniques

Abstract: A digital communication system comprises a transmitter including a (1, 0, -1) precoder (11) for precoding a unipolar input digital data stream and a bipolar converter (12) for converting the output signal of the (1, 0, -1) precoder into a bipolar signal. The bipolar signal is transmitted through a metallic transmission line (13) to a receiver. The receiver comprises an analog-to-­digital converter (14) for converting the multilevel of the transmitted signal to digital form, and a line equalization filter (15) for equalizing losses encoun­tered during propagation through the transmission line. A (1,1) equalizer (16) is provided for equalizing the output signal of the line equalization filter. A clock recovery circuit (18) derives sample timing pulses from the output of the line equalization filter. A decoder (17) responds to the sample timing pulses to detect symbols from the output signal of the (1, 1) equalizer to generate a replica of the original digital data stream.