CN-121984565-A - Microwave frequency converter control circuit, microwave frequency converter and communication system

CN121984565ACN 121984565 ACN121984565 ACN 121984565ACN-121984565-A

Abstract

The application relates to the technical field of radio frequency, in particular to a control circuit of a microwave frequency converter, which comprises a radio frequency link and a local oscillator link, wherein the radio frequency link comprises an intermediate frequency amplifying module, a mixer and a radio frequency amplifying module which are sequentially connected, a local oscillator port of the mixer is connected with the local oscillator link, the intermediate frequency amplifying module comprises two stages of intermediate frequency amplifiers which are connected in series, and a voltage control type variable attenuator which is connected between the two stages of intermediate frequency amplifiers in series, the variable attenuator is connected with a temperature compensation control circuit, and the radio frequency amplifying module comprises two stages of radio frequency amplifiers which are connected in series, and fixed attenuators are respectively connected between the input end of the radio frequency amplifying module and the adjacent two stages of radio frequency amplifiers in series. The method has the characteristics of broadband gain adjustment capability, high-precision temperature compensation mechanism and excellent port matching performance.

Inventors

CHEN XUEFU
ZHAO CHEN
LI XIAOLI
OU WENSEN

Assignees

中国电子科技集团公司第七研究所

Dates

Publication Date: 20260505
Application Date: 20260120

Claims (10)

1. A control circuit of a microwave frequency converter is characterized by comprising a radio frequency link and a local oscillator link, wherein the radio frequency link comprises an intermediate frequency amplifying module, a mixer and a radio frequency amplifying module which are sequentially connected, a local oscillator port of the mixer is connected with the local oscillator link, the intermediate frequency amplifying module comprises two stages of intermediate frequency amplifiers which are connected in series, and a voltage control type variable attenuator which is connected between the two stages of intermediate frequency amplifiers in series, the variable attenuator is connected with a temperature compensation control circuit, and the radio frequency amplifying module comprises two stages of radio frequency amplifiers which are connected in series, and fixed attenuators are respectively connected between an input end of the radio frequency amplifying module and the adjacent two stages of radio frequency amplifiers in series.
2. The microwave-inverter control circuit of claim 1, wherein the temperature-compensated control circuit comprises a thermistor network that outputs a corresponding negative pressure control signal to the control terminal of the variable attenuator based on ambient temperature.
3. The microwave-inverter control circuit of claim 1, wherein the fixed attenuator comprises a first fixed attenuator in series with an input and a second fixed attenuator in series between two stages of radio frequency amplifiers.
4. The microwave frequency converter control circuit of claim 1, wherein a local oscillator drive circuit is further connected between the local oscillator link and a local oscillator port of the mixer, and the local oscillator drive circuit comprises a fixed attenuator, a drive amplifier and a filter chip which are sequentially connected in series.
5. The microwave inverter control circuit of claim 1, wherein the rf link further comprises an intermediate frequency band pass filter disposed after the output of the intermediate frequency amplification module and an rf band pass filter disposed before the rf amplification module, the intermediate frequency band pass filter employing a parallel coupled line structure.
6. A microwave frequency converter comprising the microwave frequency converter control circuit according to any one of claims 1 to 5, wherein the local oscillator link further comprises a sampling CRO circuit and a digital loop PLL circuit, the sampling CRO circuit is configured to receive a reference signal and perform frequency multiplication and filtering, and output a first local oscillator signal, and the digital loop PLL circuit is configured to perform frequency discrimination and phase discrimination on a feedback signal output by the microwave frequency converter and the reference signal, and output a voltage-controlled voltage to a main medium oscillator CRO, and the main medium oscillator CRO outputs a local oscillator signal with a target frequency to the mixer.
7. The microwave frequency converter of claim 6, wherein the sampling CRO circuit is configured to generate control pulses via the pulse forming circuit using a predetermined reference signal, control the sampling CRO circuit to sample and lock the output of the voltage controlled medium oscillator, and output a local oscillator signal with low phase noise.
8. The microwave frequency converter of claim 6 further comprising a digital mixing loop circuit, wherein said digital mixing loop circuit comprises a mixing module, one input of said mixing module is connected to the output of said main dielectric oscillator CRO, the other input is connected to the output of said sampling CRO circuit, said mixing module mixes the signal of said main dielectric oscillator CRO with the signal of said sampling CRO circuit, and outputs an intermediate frequency beat signal to said digital loop PLL circuit for phase discrimination locking.
9. The microwave frequency converter of claim 8, wherein the isolation between the radio frequency port and the local oscillator port of the mixing module in the digital mixing loop circuit is greater than 80dBc to output a clean intermediate frequency beat signal.
10. A communication system comprising a microwave transducer according to any one of claims 6 to 9, the communication system being any one of a satellite communication system, a radar system or a microwave transmission system.

Description

Microwave frequency converter control circuit, microwave frequency converter and communication system Technical Field The present application relates to the field of radio frequency technologies, and in particular, to a microwave frequency converter control circuit, a microwave frequency converter, and a communication system. Background With the rapid development of wireless communication technology, a microwave frequency converter is used as a core component in a radio frequency signal transmission and processing system, and is widely applied to the fields of satellite communication, radar systems, microwave transmission, electronic countermeasure and the like. The microwave frequency converter is mainly used for completing the conversion between signals in different frequency bands, such as up-conversion or down-conversion, so as to meet the strict requirements of the system on the performance of signal frequency spectrum movement, linearity, gain, noise and the like. However, existing microwave inverter control circuits face a number of challenges in high frequency broadband applications. First, conventional control circuits tend to have limited gain adjustability, limited device performance, and lack effective temperature drift compensation capabilities. Under wide temperature range and extreme climate environment, the gain of the frequency converter is easy to fluctuate drastically, and the stability of the system is reduced. Second, in the design of radio frequency links in high frequency bands, such as Ku band, ka band, etc., the deterioration of port standing wave ratio VSWR and poor inter-stage matching are common problems, which can seriously affect the linearity and power transmission efficiency of the link. In addition, the quality of the local oscillation signal directly determines the signal purity after frequency conversion, and the local oscillation link in the prior art is weak in noise suppression capability and high in phase noise, so that the severe requirements of modern high-flux satellite communication or high-precision radar on the signal spectrum purity and frequency stability are difficult to meet. Therefore, it is desirable to develop a microwave inverter control circuit with broadband gain adjustment capability, high-precision temperature compensation mechanism, excellent port matching performance, and low phase noise. Disclosure of Invention Accordingly, in view of the above-mentioned problems, it is desirable to provide a microwave inverter control circuit, a microwave inverter and a communication system with broadband gain adjustment capability, which have the characteristics of high-precision temperature compensation mechanism and excellent port matching performance. In order to achieve the above purpose of the present invention, the following technical scheme is adopted: A microwave frequency converter control circuit comprises a radio frequency link and a local oscillator link, wherein the radio frequency link comprises an intermediate frequency amplifying module, a mixer and a radio frequency amplifying module which are sequentially connected, a local oscillator port of the mixer is connected with the local oscillator link, the intermediate frequency amplifying module comprises two stages of intermediate frequency amplifiers which are connected in series, and a voltage control type variable attenuator which is connected between the two stages of intermediate frequency amplifiers in series, the variable attenuator is connected with a temperature compensation control circuit, and the radio frequency amplifying module comprises two stages of radio frequency amplifiers which are connected in series, and fixed attenuators are respectively connected between an input end of the radio frequency amplifying module and the adjacent two stages of radio frequency amplifiers in series. Preferably, the temperature compensation control circuit comprises a thermistor network, and the thermistor network outputs a corresponding negative pressure control signal to the control end of the variable attenuator according to the ambient temperature. Further, the fixed attenuator comprises a first fixed attenuator connected in series with the input end and a second fixed attenuator connected in series between the two stages of radio frequency amplifiers. Furthermore, a local oscillation driving circuit is also connected between the local oscillation link and the local oscillation port of the mixer, and the local oscillation driving circuit comprises a fixed attenuator, a driving amplifier and a filter chip which are sequentially connected in series. Furthermore, the radio frequency link also comprises an intermediate frequency band-pass filter arranged behind the output end of the intermediate frequency amplifying module and a radio frequency band-pass filter arranged in front of the radio frequency amplifying module, wherein the intermediate frequency band-pass filter adopts a parallel coupling lin