| 摘要 |
A method and apparatus for reducing the introduction of alias frequencies in the processing of signals. A sequence of jittered pulses is provided, each pulse occurring during one of a sequence of time intervals of duration T at a time determined by a sequential one of a set of independent random numbers having a uniform probability density in a region bounded by zero and T. A signal processing operation, such as sampling a signal or synthesizing a signal having a desired frequency specified by a control signal, is performed in response to the jittered pulses. Setup time aliasing is avoided by alternating between two signal processors, each driven by one of a pair of phase-related sequences of jittered pulses, or, in the case of a frequency synthesizer, by jittering the output signal rather than the input pulses. Phase noise in a synthesized signal is reduced by scaling the control signal according to the durations of the time intervals between successive jittered pulses.
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