| 摘要 |
<p>In the illustrative embodiment, the inventive system includes a low-bit digital-to-analog converter (68) for converting a first signal at a reference frequency to a digital signal. A delta-sigma converter is included for suppressing noise in the digital signal within the predetermined range of the reference frequency and providing a noise-shaped signal in response thereto. A bandpass filter (72) filters out the out-of-band noise and provides an accurate periodic signal which lacks glitch noise. In a particular embodiment, the inventive system further includes a direct digital synthesizer (42) for providing the first signal at the first frequency and the accurate reference periodic signal is supplied as reference signal to a phase-locked loop (50).</p> |
