Telecommunications – Transmitter and receiver at separate stations – Distortion – noise – or other interference prevention,...
Patent
1993-08-09
1994-11-01
Kuntz, Curtis
Telecommunications
Transmitter and receiver at separate stations
Distortion, noise, or other interference prevention,...
455296, 333 18, 375 14, 375101, H04B 1500, H04B 110, H03H 730
Patent
active
053614003
ABSTRACT:
In a receiver an apparatus and method substantially reduces time dispersion and multipath distortion in a received signal. An equalizer (109), including taps having gain coefficients, produces an equalized signal (110) responsive to the received signal (107) and an adaptive process signal (137), wherein the gain coefficients are adjusted responsive to the adaptive process signal (137). A first mixer (111) mixes the equalized signal (110) and a reference carrier signal (115) to produce a recovered modulated signal (119). A detector (112) detects an estimate signal (129) responsive to the recovered modulated signal (119). An error signal generator (139) generates an error signal (141) responsive to a difference between the recovered modulated signal (119) and the estimate signal (129). A second mixer (147) mixes the error signal (141) and the reference carrier signal (115) to produce the adaptive process signal (137). In a preferred embodiment, a third mixer (153) mixes the estimate signal (129) and the reference carrier signal (115) to produce a feedback signal (135) for at least one tap. The present invention advantageously permits the equalizer (109) and the detector (112) to optimally perform their respective functions while coupled together to maximize the receiver's performance.
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Dennis Donald W.
Goode Steven H.
Kazecki Henry L.
Charouel Lisa
Kaschke Kevin D.
Kuntz Curtis
Motorola Inc.
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