| 摘要 |
PURPOSE: A technique for removing radio-frequency noise from received signals is provided for high speed data communications. CONSTITUTION: Radio-frequency noise is removed by adaptively estimating the radio-frequency noise during data transmission using information obtained when no data is actually being transmitted. A receiver has a transformer having an input terminal coupled to a transmission medium, an output terminal for outputting a differential signal, and a reference terminal for outputting a reference noise signal; a radio frequency noise canceller coupled to transformer for canceling certain radio frequency noise from the differential signal to produce a noise-canceled differential signal; and processing circuitry for decoding the noise-canceled differential signal to obtain the data. The radio frequency noise canceller includes at least an adaptive filter for producing a noise cancellation signal by filtering a reference noise signal based on filter parameters, a subtractor for subtracting the noise cancellation signal from the differential signal to produce the noise-canceled differential signal, and an update circuit for enabling, at predetermined times, modification of the parameters of adaptive filter based on the then existing noise-canceled differential signal.
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