摘要 |
A digital frequency modulator is disclosed. In the digital frequency modulator, a first gain controller multiplies an input digital signal by a first gain determined according to a required modulation frequency, a phase accumulator accumulates the input digital signal and generates a phase accumulation according to a required phase resolution to output the phase accumulation within a predetermined output range. A second gain controller multiplies the output of the phase accumulator by a second gain determined according to the required modulation frequency and the first gain. A phase modulator outputs cosine and sine values having a phase corresponding to the second-gain controlled signal.
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