Patent ID: 7756192
Filing Date: 2010-07-13
Classification: H04B

Abstract:
1. An apparatus for despreading a sum of spread signals of the type having a plurality of signal processing paths for receiving the sum of spread signals that are respectively spread with different spreading codes each of which two or more channels are assigned to, each signal processing path corresponding to one of the different spreading codes comprising: means for subtracting estimated spread signals corresponding to the other signal processing paths from the sum of spread signals to produce a modified sum of spread signals; means for despreading the modified sum of spread signals with the corresponding spreading code to produce a despread modulated signal; means for separating the despread modulated signal into signals that respectively correspond to the two or more channels assigned to the corresponding spreading code; means for estimating symbol values of the signals corresponding to the two or more channels respectively; means for producing an estimated modulated signal corresponding to the spreading code from the estimated symbol values of the two or more channels; and means for spreading the estimated modulated signal according to the spreading code to produce one of the estimated spread signals for input to the subtracting means for the other signal processing paths so that noise is minimized when a modulated signal representing a particular communication channel within the despread modulated signal is demodulated.