Near-carrier-frequency low-phase-noise frequency synthesizer

Abstract

The invention discloses a near-carrier-frequency low-phase-noise frequency synthesizer, and the frequency synthesizer comprises a triode frequency multiplier, a filter, a triode amplifier and a phase-locked loop circuit, which are connected sequentially. The triode tube frequency multiplier inputs a 10 MHz reference signal and performs low-noise frequency multiplication. The filter performs the narrowband filtering of the frequency-doubled signal, and the triode amplifier amplifies the filtered signal. The phase-locked loop circuit includes a phase discriminator, a loop filter, a voltage-controlled oscillator and a frequency divider, which are connected sequentially. The phase discriminator receives an amplified signal from the triode amplifier and performs phase discrimination with an RFfeedback signal from the frequency divider. The loop filter performs low-pass filtering of a voltage error signal outputted by the phase discriminator as a control signal, and then sends the control signal to a voltage control end of the voltage-controlled oscillator. The voltage controlled oscillator outputs an RF signal. The triode frequency multiplier of the present invention not only improvesthe reference frequency, but also reduces the phase noise deterioration at the carrier signal of 1Hz, and the phase-locked loop circuit has a lower near carrier frequency 1 Hz phase noise substrate.

Description

technical field [0001] The invention belongs to the technical field of wireless communication, and in particular relates to a near-carrier frequency low phase noise frequency synthesizer. Background technique [0002] A frequency synthesizer is based on one or more high-performance reference source signals, through hardware circuits and software algorithms to achieve mathematical transformation of frequency, to generate a series of new discrete frequencies with the same accuracy and stability as the reference source signal Signal system. Frequency synthesizers usually provide high-performance local oscillator signals for electronic communication transceiver equipment, and their performance directly affects the quality of the entire electronic system. Phase-locked loop technology is a method to realize a frequency synthesizer. A typical phase-locked loop circuit used to realize a frequency synthesizer usually consists of an input reference source, a phase detector, a loop fi...

AI Technical Summary

Problems solved by technology

In the conventional communication system, there is no such index requirement for the frequency synthesizer, and there is no relevant report

Images