Quadrature push-push voltage-controlled oscillator based on circle structure

Abstract

The invention relates to a quadrature push-push voltage-controlled oscillator based on a circle structure. The oscillator comprises a four-stage delay unit, the phase relation between output signals in a circle oscillator constructed by a four-stage inverting amplifier is combined with a harmonic wave selection element to extract secondary harmonic waves in the output signals, mutually quadrature phases of the extracted secondary harmonic waves are used as the output of the circle structure so as to form the push-push voltage-controlled oscillator in quadrature output. Under the condition that the process is limited, the structure can effectively improve the frequency of the quadrature local oscillator output signal, and the structure can be used for providing a high-quality quadrature oscillator signal for millimeter wave, submillimeter wave, in particular a terahertz frequency band transceiving front end.

Description

technical field [0001] The invention belongs to the technical field of microelectronics and relates to an orthogonal push-push voltage-controlled oscillator based on a ring structure. Background technique [0002] According to different structures, wireless transceiver front-ends can be divided into superheterodyne receivers, low-IF receivers, and zero-IF receivers. Among them, zero-IF receivers have attracted more and more attention because they can be integrated on a single chip. In this structure, the radio frequency signal is mixed with two orthogonal local oscillator signals to directly generate the baseband signal. The phase error and amplitude mismatch of the two quadrature local oscillator signals will directly affect the image rejection capability and demodulation performance of the receiver. At the same time, since the circuit that generates the local oscillator signal works at the highest frequency of the circuit, its frequency output capability and power consump...

AI Technical Summary

Problems solved by technology

For quadrature voltage-controlled oscillators, it is quite difficult to generate such a high-frequency oscillation signal, especially when the required frequency is close to the cut-off frequency f of the oscillator's active components T Time

For passive polynomial filters, in addition to the above-mentioned problems, it is also quite difficult to realize an amplifier with a gain of 6dB in the above-mentioned frequency band

All these pose serious challenges to the generation of orthogonal local oscillator signals in the terahertz frequency band and the development of terahertz wireless communication

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