CN-224218364-U - Broadband anti-interference down-conversion device and radio frequency receiving system

Abstract

The utility model discloses a broadband anti-interference down-conversion device and a radio frequency receiving system, and relates to the wireless communication technology. The device comprises a first frequency converter, a second frequency converter, a power divider and a local oscillation unit, wherein the first frequency converter and the second frequency converter realize two-stage frequency conversion of radio frequency signals, the second frequency converter adopts a double-channel ping-pong switching structure, two channels are connected with the output end of the first frequency converter through the power divider, and the local oscillation unit respectively provides independent local oscillation signal input for the first frequency converter, the second frequency converter and the local oscillation unit. The device realizes broadband and high dynamic interference suppression performance by combining two-stage frequency conversion with a double-channel ping-pong switching structure.

Inventors

• LUO ZHIGANG
• SUN LIANG
• SONG XU

Assignees

• 成都旭思特科技有限公司

Dates

Publication Date

20260508

Application Date

20250430

Claims (10)

1. 1. A broadband anti-interference down-conversion device, comprising: The first frequency converter is used for outputting a first intermediate frequency signal after mixing the received radio frequency signal with a first local oscillation signal; The power divider is connected with the output end of the first frequency converter and is used for dividing the power of the first intermediate frequency signal into two paths; The first frequency conversion branch is used for mixing the first intermediate frequency signal with a second local oscillation signal and then outputting a second intermediate frequency signal, the second frequency conversion branch is used for mixing the first intermediate frequency signal with the three local oscillation signals and then outputting a second intermediate frequency signal, and the change-over switch is used for selecting and outputting the second intermediate frequency signal of the first frequency conversion branch or the second frequency conversion branch; and the local oscillation unit is respectively connected with the first frequency converter, the first frequency conversion branch and the second frequency conversion branch and is used for providing local oscillation signals required by frequency mixing for the first frequency converter, the first frequency conversion branch and the second frequency conversion branch.
2. 2. The broadband anti-interference down-conversion device according to claim 1, wherein the first frequency converter comprises a low noise amplifier, a band pass filter, a mixer, an intermediate frequency filter and an intermediate frequency amplifier connected in sequence, and an output of the intermediate frequency amplifier is used as an output of the first frequency converter.
3. 3. The broadband anti-interference down-conversion device according to claim 1, wherein the first frequency conversion branch and the second frequency conversion branch each comprise a band-pass filter, a mixer, an attenuator and a low-pass filter which are sequentially connected, an output end of the low-pass filter is connected with the switch, and an input end of the band-pass filter is used as an input end of the second frequency converter.
4. 4. A broadband anti-interference down-conversion device according to claim 2 or 3, wherein the mixer is of the HMC8193 type.
5. 5. A broadband anti-interference down-conversion device according to claim 3, wherein the band-pass filter is a tunable vibration filter.
6. 6. A broadband anti-interference down-conversion device according to claim 3, wherein the attenuator is a digitally controlled attenuator HMC624.
7. 7. The broadband anti-interference down-conversion device according to claim 1, wherein the local oscillation unit comprises a first local oscillation unit, a second local oscillation unit and a third local oscillation unit, the first local oscillation unit is used for providing a first local oscillation signal, the second local oscillation unit is used for providing a second local oscillation signal, the third local oscillation unit is used for providing a third local oscillation signal, and the second local oscillation unit and the third local oscillation unit adopt a common-source phase-locked loop.
8. 8. The broadband anti-interference down-conversion device according to claim 7, wherein the local oscillation unit further comprises a phase calibration unit, the phase calibration unit being integrated with the second local oscillation unit and the third local oscillation unit, and configured to dynamically compensate phases of the second local oscillation unit and the third local oscillation unit.
9. 9. The broadband anti-interference down-conversion device according to claim 1, wherein the change-over switch adopts a two-stage three-switch-chip serial structure and comprises a first switch chip, a second switch chip and a third switch chip, the first switch chip and the second switch chip are respectively connected in series with the rear ends of the first frequency conversion branch and the second frequency conversion branch and are connected in series with the third switch chip, and the third switch chip is connected in series with the combined output ends of the first frequency conversion branch and the second frequency conversion branch.
10. 10. A radio frequency receiving system comprising a broadband anti-interference down-conversion device according to any one of claims 1-9.

Description

Broadband anti-interference down-conversion device and radio frequency receiving system Technical Field The utility model relates to the technical field of wireless communication, in particular to a broadband anti-interference down-conversion device and a radio frequency receiving system. Background With the rapid development of wireless communication, radar detection and electronic countermeasure technologies, the demands of the radio frequency receiving system for broadband coverage, high-frequency band adaptability and dynamic anti-interference performance are increasingly urgent. The down-conversion device is used as a core front-end module of the radio frequency receiving link and bears the key task of converting a high-frequency radio frequency signal into a medium-low frequency signal, and the performance of the down-conversion device directly influences the sensitivity, the anti-interference capability and the signal processing precision of the system. Particularly in high-frequency application scenes such as satellite communication, millimeter wave radar and the like, the traditional down-conversion architecture has the problems of limited bandwidth, sensitive phase noise, insufficient dynamic interference suppression and the like. Traditional single-stage down converters are limited by the mixer operating bandwidth and local oscillator frequency range, and are difficult to cover the broadband requirements of GHz to tens of GHz at the same time. For example, in Ka band (26.5-40 GHz) applications, single stage mixers often sacrifice linearity or noise performance to achieve high frequency coverage, resulting in reduced overall system performance. The two-stage frequency conversion architecture is adopted to expand the working bandwidth, for example, two phase-locked loops are used for respectively generating two corresponding local oscillators, one local oscillator is selected to be output through a switch, then the local oscillator is mixed with radio frequency signals to finally obtain intermediate frequency signals, and the two local oscillator signals are switched to obtain mixed output with different frequencies. However, when the local oscillation signal frequency is switched, phase jump is easy to generate, so that transient distortion of the signal is caused, and the dynamic anti-interference efficiency is obviously reduced. In summary, in the existing satellite communication system, the working bandwidth and anti-interference performance of the down converter are still to be further improved. Disclosure of utility model The utility model provides a broadband anti-interference down-conversion device and a radio frequency receiving system, which solve the problems of insufficient working bandwidth and dynamic interference suppression of the existing satellite down-conversion device. The utility model is realized by the following technical scheme: in a first aspect, a broadband anti-interference down-conversion device is provided, including: the first frequency converter is used for mixing the received radio frequency signal with a first local oscillation signal to output a first intermediate frequency signal; The power divider is connected with the output end of the first frequency converter and is used for dividing the power of the first intermediate frequency signal into two paths; The first frequency conversion branch is used for mixing the first intermediate frequency signal with a second local oscillation signal to output a second intermediate frequency signal, the second frequency conversion branch is used for mixing the first intermediate frequency signal with the three local oscillation signals to output a second intermediate frequency signal, and the change-over switch is used for selecting and outputting the second intermediate frequency signal of the first frequency conversion branch or the second frequency conversion branch; and the local oscillation unit is respectively connected with the first frequency converter, the first frequency conversion branch and the second frequency conversion branch and is used for providing local oscillation signals required by frequency mixing for the first frequency converter, the first frequency conversion branch and the second frequency conversion branch. Aiming at the problems of insufficient bandwidth and reduced dynamic resistance of two-stage local oscillation switching frequency conversion in single-stage frequency conversion, the utility model combines a two-stage frequency conversion and a two-channel ping-pong switching architecture, outputs a first intermediate frequency signal through the frequency mixing of a first frequency converter, outputs a second intermediate frequency signal with lower frequency through the frequency mixing of a second frequency converter, obviously improves the anti-interference performance, adopts a two-channel ping-pong switching structure in the second-stage frequency conversion, respectively receives two lo