| 摘要 |
A receiver (10) for extracting a desired signal component (70) from a received signal, which received signal contains the desired signal component (70) and may contain an interfering signal component (72), wherein the receiver (10) comprises a first mixer (16) which generates an intermediate frequency signal containing a frequency-shifted version of the received signal and a frequency-shifted version of an image of the received signal, the receiver further comprising: a second mixer (26) for shifting the desired signal component (70) of the intermediate frequency signal such that it is centred on a baseband frequency, so as to generate a first composite signal containing the shifted desired signal component (70) and a shifted version of any interfering signal component (76) contained in the image of the received signal; a third mixer (30) for shifting an image of the desired signal such that it is centred on the baseband frequency, so as to generate a second composite signal containing the shifted image (74) of the desired signal component and a shifted version (72) of any interfering signal component contained in the received signal; an estimator (34) for estimating, from the first and second composite signals, a coefficient indicative of the amount of the interfering signal (72) component that is present with the desired signal component (70) in a selected one of the composite signals; a multiplier (36) for scaling the complex conjugate of the selected composite signal by the coefficient so estimated; and an adder (38) for subtracting the scaled signal output by the multiplier (36) from the other composite signal to obtain a scaled version of the desired signal component
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