Patent ID: 8477890

Claim:
A method of detecting a desired signal by a radio or receiver in a communications system, wherein the desired signal is modulated to obtain N possible symbols and is received in the presence of a constant modulus (CM) interferer that produces M possible symbols, including the steps of: obtaining observation samples from a signal recovery stage in the receiver, the samples corresponding to the desired signal and the interferer as received simultaneously at the receiver; defining N symbol points each corresponding to one of the N possible symbols modulated on the desired signal; defining N observation constellations each having M constellation points corresponding to the M possible symbols produced by the interferer; defining a circular observation perimeter for each observation constellation, wherein the perimeter includes the M constellation points of the constellation and has a radius corresponding to the strength of the interferer; centering the observation perimeter of each of the N observation constellations on a corresponding one of the N defined symbol points; for a given observation sample obtained from the signal recovery stage, determining on which observation perimeter lies a point that is nearest to the given observation sample; and selecting, for the given observation sample, the symbol point about which the determined observation perimeter is centered as a symbol of the desired signal.