An interference robust CDMA demodulator that uses spectral correlation properties

A technique is presented for effectively rejecting CDMA interference. No knowledge of the interfering signals is required. The demodulator uses a cyclic Wiener filter (FRESH filter) to decrease the bit error rate, and increase spectral efficiency. In some situations, the bit error rate is reduced by more than two orders of magnitude and capacity is tripled. For despreading and demodulating the signal-of-interest, the demodulator takes on a structure similar to that of fractionally-spaced equalizers. Substantial improvement over the conventional correlation receiver is obtained by exploiting spectral correlation of the signal-of-interest and the multiple access interference even with severe multipath distortion. The computational complexity of the receiver is equivalent to that of conventional equalizers