Reliable decision directed adaptation in a communication system employing forward error control

Abstract

The present invention provides a method and apparatus for selectively updating an adaptive element in a communications receiver based on a determination that the received data is accurate. When inaccurate data is received, the system determines that using that data to update the adaptive element will not be beneficial and excludes the data from being sent to the adaptive element. One mechanism for determining that data has been incorrectly received is the calculation of syndromes as part of a Forward Error Control (FEC) system. Detection of errors through use of the syndrome calculation can be supplemented through windowing to make a determination as to whether a number of received bits should be used or disregarded by the adaptive element. The adaptive element can comprise any number of decision-directed loops including adaptive processors and carrier and timing recovery loops.