Patent ID: 6128337
Filing Date: 2000-10-03
Classification: H04B,H04L

Abstract:
A method for discrimination of a multipath signal in a received composite signal that includes a direct, distortion-free signal, the method comprising the steps of:transmitting a transmitted digital signal that includes a transmitted direct signal with an arbitrary direct signal bit pattern and includes an indicium signal with a selected indicium signal bit pattern whose indicium signal bits are separate from, and form an indicium signal bit pattern that is distinguishable from, the direct signal bits, wherein the indicium signal bit pattern includes a frequency for bit value transitions that is higher than a maximum frequency for bit value transitions for the direct signal bit pattern;receiving at a signal receiver a received composite digital signal that is a result of propagation of the transmitted digital signal from the source of the transmitted digital signal to the signal receiver, where the received composite digital signal includes received indicium signal bits and received direct signal bits that result from propagation of the indicium signal bits and of the direct signal bits, respectively;separating the received indicium signal bits from the received composite signal to produce a received remainder signal that includes at least a portion of the received composite signal not including any bits that correspond to the received indicium signal bits;comparing the received indicium signal bits with bits from a selected reference signal that is substantially a replica of the transmitted indicium signal, and determining a signal modification that will convert the reference signal into the received indicium signal; andapplying an inverse of the signal modification to the received remainder signal to determine an enhanced received composite signal that has less signal distortion than the received remainder signal.