Coupling voltage-controlled oscillator based on four-port coupling network

Abstract

The invention belongs to the technical field of wireless communication, and relates to a voltage-controlled oscillator, in particular to a coupling voltage-controlled oscillator based on a four-port coupling network. The coupling voltage-controlled oscillator is used for solving the problems that a traditional coupling voltage-controlled oscillator has the requirement for the symmetry of a coupling network, the coupling network is not prone to achieving absolute symmetry, the purpose of reducing phase noise cannot be achieved, and more area is occupied. According to the invention, the invention is composed of four identical voltage-controlled oscillators and a four-port coupling network, and a tail resistor is connected in series to a common-mode path to replace an LC parallel resonant cavity, so that the chip area is greatly reduced while the phase noise is effectively reduced. Moreover, a common mode point coupling mode is adopted, so that a coupling network is more symmetrical, wiring is shorter, mismatch is reduced, noise at a second harmonic position can be greatly reduced, and the possibility that phase noise is deteriorated due to the fact that the second harmonic noise is down-converted to the position near fundamental waves is reduced.

Description

technical field [0001] The invention belongs to the technical field of wireless communication, relates to a voltage-controlled oscillator, in particular to a coupled voltage-controlled oscillator based on a four-port coupling network. Background technique [0002] With the advent of the 5G era, communication technology has increasingly become a standard for measuring a country's scientific and technological strength. For radio frequency communication systems, frequency sources provide a stable frequency for up-mixing or down-mixing to facilitate signal processing, and are widely used In mobile communication terminals, military communication systems and satellite communication systems. As the core of the frequency synthesizer, the voltage-controlled oscillator seriously affects the signal quality after frequency mixing in the system. Therefore, optimizing the phase noise of the voltage-controlled oscillator has become an effective means to improve system performance. [0003...

AI Technical Summary

Problems solved by technology

[0007] Aiming at the above-mentioned traditional coupled voltage-controlled oscillator’s requirements for the symmetry of the coupling network, the coupling network is not easy to achieve absolute symmetry, not only can not achieve the purpose of reducing phase noise but also occupies more area; the purpose of the present invention is to provide a new The coupled voltage-controlled oscillator based on the four-port coupling network reselects the coupling point, which can not only achieve the coupling effect but also achieve a completely symmetrical layout, effectively utilizing the layout area and reducing the phase noise; at the same time, it overcomes the secondary Disadvantages of Harmonic Suppression Method Requiring Inductors

Images