| 摘要 |
<p>A signal processing channel and method for reducing intersymbol interference in a sequence (98) of data symbols (78 and 80) includes a pre-shaping filter (42) for sharpening leading edges of data symbols and providing trailing edges that approximate a decaying exponential. The output (100) of the pre-shaping filter is combined with a cancellation output (102) from a resistance-capacitance circuit (66 and 68; 72 and 74; 81 and 83) having a time constant selected to provide pulse responses (88) that complement the exponentially decaying trailing edges. The combination of the shaped output and the cancellation output is input to a slicer (44) or other decision device. The 2-level output (106) from the slicer is an input to a decision feedback filter (60) that generates the cancellation output. In addition to the resistance-capacitance circuit, the decision feedback filter includes a delay (64; 70; 77) to time properly the coincidence of the cancellation output with the shaped output from the pre-shaping filter. Preferably, the signal processing channel and method include a gain circuit (36) for setting the peaks of the shaped signals and include adaptive adjustment of the gain, the sharpening by the pre-shaping filter, and the RC time constant of the decision feedback filter. <IMAGE></p> |
