| 摘要 |
A direct digitally synthesizer-based, injection locked oscillator includes a direct digital synthesizer for generating a digitally synthesized signal at frequency f0, an analog oscillator circuit for generating an analog signal at frequency f1 and a filter coupled to the direct digital synthesizer for filtering the digitally synthesized signal to provide a signal at frequency Nf0. N may be an integer from 1 to 10. Also included is a coupler to couple the filtered, digitally synthesized signal into the analog oscillator to lock the frequency of the analog output signal to the frequency of the digitally synthesized signal such that the frequency f1 is equal to the frequency Nf0. The coupler also electrically couples the analog signal from the analog oscillator circuit to a second filter to filter the analog signal. An amplifier electrically coupled to the second filter amplifies the filtered signal to provide an analog oscillator output signal. The direct digital synthesizer may be used to high-order, sub-harmonically injection lock the analog oscillator circuit thereby providing an output signal reflecting a frequency up-conversion in order to broaden the frequency range of the synthesized analog output signal beyond that of the direct digital synthesizer.
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