Patent ID: 8493953
Filing Date: 2013-07-23
Classification: H04B

Abstract:
1. An apparatus for mitigating multi-user interference in reception of a code division multiple access signal having a plurality of spread user symbol streams each spread by a corresponding one of a plurality of spreading codes comprising: a first summer having an input configured to accept the code division multiple access signal and configured to subtract a reconstructed signal from the code division multiple access signal to produce a difference signal; a plurality of matched filters coupled to the first summer and configured to accept the difference signal and output a plurality of matched filter outputs; a plurality of second summers coupled to the plurality of matched filters and configured to sum each one of the plurality of matched filter outputs with a corresponding one of a plurality of weighted symbol estimates to produce a plurality of adjusted matched filter outputs; a plurality of estimators coupled to the plurality of second summers and configured to estimate a plurality of estimated symbols from the plurality of adjusted matched filter outputs, wherein each one of the plurality of estimated symbols corresponds to one of the plurality of spread user symbol streams; a weighted symbol generator coupled to the plurality of estimators and coupled to the plurality of second summers and configured to generate the plurality of weighted symbol estimates from the plurality of estimated symbols; and a reconstructor coupled to the weighted symbol generator and coupled to the first summer and configured to re-spread the plurality of weighted symbol estimates using the plurality of spreading codes to produce the reconstructed signal.