| 摘要 |
<p>Spread spectrum receivers for reducing interference are described, particularly the interference observed at a user-end terminal in a W-CDMA 3G mobile communications system. Interpath interference which arises due to non-zero cross and auto correlation of more than one spreading code is suppressed by estimating a transmitted signal stream for a number of CDMA channels and/or multipaths, respreading this estimated signal and subtracting non-orthogonal interference contributions from a received signal before despreading a desired signal. Alternatively the estimated signal streams can be multiplied by the cross correlation between their spreading code and the desired signal spreading code and subtracted from an already despread symbol. The techniques provide an improved bit error rate or equivalently, enhanced capacity for a digital mobile communications network, and is particularly useful for cancelling pilot interference. Usable in space time transmit diversity (STTD) systems.</p> |
