Patent ID: 8433001

Claim:
A method of recovering a symbol from a signal received by a communication receiver, comprising: inputting the signal to each of a plurality of primary intermediate frequency filters (IFFs), each IFF outputting a respective IFF output that may be chosen to provide the recovered symbol, wherein the plurality of primary IFFs comprise a nominal primary IFF, a higher frequency primary IFF and a lower frequency primary IFF, the nominal primary IFF having a center frequency f1 and a bandwidth B1 and outputting a first IFF output, the higher frequency primary IFF having a higher center frequency f2 offset a non-zero amount f0 above f1 and having a bandwidth B2 greater than B1 and outputting a second IFF output, and the lower frequency primary IFF having a lower center frequency f3 offset the non-zero amount f0 below f1 and having the bandwidth B2 and outputting a third IFF output; performing signal recovery on the IFF output of each of the plurality of primary IFFs, to obtain a plurality of corresponding recovered signals each associated with a respective one of the plurality of primary IFFs, and a plurality of corresponding error values each associated with a respective one of the plurality of primary IFFs; inputting each of the plurality of error values to at least one of a plurality of secondary filters, to generate a signal criterion associated with each corresponding recovered signal; inputting each of the plurality of error values, in parallel with the secondary filters, to at least one of a plurality of tertiary filters, and measuring the output of each of the plurality of tertiary filters, to generate a quality metric associated with each corresponding recovered signal; selecting the recovered signal associated with the nominal primary filter, and also selecting any other recovered signal out of the plurality of recovered signal that has an associated signal criterion below a given threshold value, to produce one or more selectable recovered signals; and choosing and outputting an output signal as a particular one of the one or more selectable recovered signals that has a most favorable associated quality metric.