Multi-cavity coupled low-phase noise voltage-controlled oscillator

Abstract

The invention discloses a multi-cavity coupled low-phase noise voltage-controlled oscillator. A plurality of voltage-controlled oscillators are coupled to each other by the circuit of the voltage-controlled oscillator to improve phase noise performance, and a current multiplexing technology is used to reduce power consumption of the circuit. The circuit of the voltage-controlled oscillator includes a first voltage-controlled oscillator, a second voltage-controlled oscillator, a third voltage-controlled oscillator and a fourth voltage-controlled oscillator which are coupled to each other. The negative resistance unit circuit of each voltage-controlled oscillator adopts a current multiplexing structure to reduce power consumption and remove the deterioration caused by the second harmonic ofthe common mode node to the phase noise, and further improve the phase noise performance. The low-phase noise voltage-controlled oscillator provided by the invention is capable of effectively improving phase noise performance.

Description

technical field [0001] The invention belongs to the technical field of radio frequency integrated circuits, and in particular relates to a voltage-controlled oscillator with low phase noise. technical background [0002] As one of the core modules in the wireless communication system, the voltage-controlled oscillator is used to generate a signal with a stable frequency. It is often used to provide a reference clock for a digital circuit or provide a local oscillator signal required for up-and-down conversion for the transmission and reception links. As a key index to measure the performance of the voltage-controlled oscillator, phase noise directly affects the performance index of the entire system, so the voltage-controlled oscillator has always been a key technology in the field of integrated circuit design. The rapid development of wireless communication technology puts forward higher requirements on the phase noise performance of voltage-controlled oscillators. [00...

AI Technical Summary

Problems solved by technology

However, due to factors such as skin effect and high substrate loss, the quality factor obtainable by on-chip inductors is limited.

On the other hand, as the feature size of the CMOS process shrinks, the power supply voltage decreases, and the output signal amplitude of the voltage-controlled oscillator also decreases.

This makes it difficult to optimize the design for low phase noise

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