Ultra-wideband low-spurious double-phase-locked loop frequency source

Abstract

The invention discloses an ultra-wideband low-spurious double-phase-locked loop frequency source, which comprises a reference clock signal, a first-stage phase-locked loop part, a filtering part and asecond-stage phase-locked loop part, wherein the reference clock signal provides a reference signal for the first-stage phase-locked loop part; the first-stage phase-locked loop part performs calculation according to the reference clock signal and the output frequency of the second-stage phase-locked loop, and selects a low-stray and low-noise frequency corresponding to the output frequency of the second-stage phase-locked loop; the filtering part performs narrow-band filtering on the low-spurious frequency points output by the first-stage phase-locked loop part, and a filtered signal can beused as a reference signal of a second-stage phase-locked loop; and the second-stage phase-locked loop part performs broadband frequency modulation according to the reference signal provided by the preceding stage to obtain a broadband signal with low spurious and low phase noise. The low-spurious, low-noise and wide-band design target is achieved, spurious indexes can be improved, meanwhile, thecircuit design is simple and easy to achieve, the reliability of the system can be improved, and good economic benefits and application prospects are achieved.

Description

technical field [0001] The invention relates to a frequency source design technology, in particular to an ultra-wideband low stray double phase-locked loop frequency source. Background technique [0002] In an electronic system, the clock is equivalent to the heart of the system, and the performance of the clock signal directly affects the performance and stability of the system. With the development of electronic technology, the performance requirements of clock signals are getting higher and higher, so the role of frequency sources in electronic communication systems is becoming more and more important. In the RF front-end of systems such as radar communication, wireless communication, microwave test equipment, and spectrum monitoring, it is necessary to use microwave frequency sources with broadband, low spurious, and low phase noise to improve the anti-interference ability of the system and the confidentiality of communication. With the continuous update and development...

AI Technical Summary

Problems solved by technology

With the use of these technologies, the existing frequency sources can basically meet the various requirements of different frequency bands and low phase noise, but at the same time it is accompanied by some problems, such as spurious problems

In general, a single frequency synthesis technology, whether it is DDS or a phase-locked loop, can only rely on selecting a specific frequency point in the frequency source to avoid spurs or use filters to remove spurs

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