Frequency generating device and frequency generating method

Abstract

The invention discloses a frequency generating device comprising: a base frequency generating circuit, used to generate a reference frequency; a frequency synthesis circuit, connected to the base frequency generation circuit, used to generate a corresponding synthesized frequency according to the configuration parameters of the reference frequency and the frequency synthesis circuit; Frequency; frequency extraction circuit, connected with frequency synthesis circuit, used to extract high-order image frequency from synthesized frequency; phase-locked loop circuit, connected with frequency extraction circuit, used for configuration parameters according to high-order image frequency and phase-locked loop circuit Output the corresponding output frequency. The invention also discloses a frequency generating method. Through the above method, the present invention can reduce phase noise and spurs while realizing fast frequency hopping and high frequency resolution.

Description

technical field [0001] The invention relates to the technical field of electronic circuits, in particular to a frequency generating device and a frequency generating method. Background technique [0002] The development of frequency hopping communication technology is very rapid, and it has the characteristics of anti-interception and anti-jamming. The frequency hopping frequency source is the core of the frequency hopping technology, and its quality will directly affect the performance of the entire system. The faster the locking time, the higher the frequency jump speed, and the better the anti-intercept and anti-jamming performance. Phase noise and spurs are also extremely important to improve adjacent channel immunity and anti-blocking. Therefore, designing a fast frequency hopping frequency source with low spurious, low phase noise and high frequency resolution is particularly important for frequency hopping technology. [0003] At present, for FM frequency sources, ...

AI Technical Summary

Problems solved by technology

In the first scheme, the VCO (Voltage-Controlled Oscillator, Voltage Controlled Oscillator) of the fractional frequency division dual PLL leaks and interferes with each other, and the loop bandwidth is too narrow, the anti-vibration ability is weak, and the frequency will drift with the vibration; in the second In this scheme, the fundamental frequency f output by DDS 0 As the reference frequency of PLL, the reference frequency is not higher than f clk / 2, resulting in an increase in the multiplier of the PLL, which in turn leads to higher output spurs of the PLL

In the third scheme, take the base frequency of the DDS output and mix it with the clock to increase the frequency to f clk +f 0 Finally, as the reference frequency of the PLL, the circuit structure of this scheme is complex, and high-order spurs are likely to be generated after frequency mixing

Images