低噪声下变频器及收发信机
By employing multiple low-noise amplifiers in series and low-dropout regulators in Ka satellite communication, the problems of complex dual-channel LNB structure and poor RF performance were solved, achieving good matching of signal transmission channels and miniaturization of the product, and reducing the noise figure.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- RIGO (GUANGZHOU) COMM TECH CO LTD
- Filing Date
- 2025-07-18
- Publication Date
- 2026-07-17
AI Technical Summary
In existing technologies, dual-channel LNBs have complex structures that are not conducive to miniaturization and have poor radio frequency performance. In particular, in Ka satellite communications, the use of waveguide isolators and radio frequency switches leads to an increase in the system noise figure.
Multiple low-noise amplifiers are connected in series, and the signal channel is turned on and off by an enable-controlled low-dropout regulator. Combined with a bandpass filter and a phase-locked loop, good matching of the signal transmission channel is achieved, avoiding the use of waveguide isolators and RF switches.
It achieves good matching of signal transmission channels, ensuring RF performance, while product miniaturization helps reduce the noise figure and increase the available power of the system.
Smart Images
Figure CN224521042U_ABST
Abstract
Claims
1. A low noise downconverter, characterized by, It includes a dual-channel switching unit, a first bandpass filter, a phase-locked loop, a mixer amplifier unit, and an MCU; The dual-channel switching unit is provided with two signal channels, and the two input terminals of the dual-channel switching unit correspond to different signal channels and are used to receive high-frequency signals. The MCU is connected to the dual-channel switching unit, and the MCU is used to control the conduction or cutoff of the signal channels in the dual-channel switching unit to output one signal. The input terminal of the first bandpass filter is connected to the output terminal of the dual-channel switching unit, and the output terminal of the first bandpass filter is connected to the first input terminal of the mixer amplifier unit. The second input terminal of the mixing amplifier unit is connected to the output terminal of the phase-locked loop, the reference terminal of the mixing amplifier unit is connected to the input terminal of the phase-locked loop, the output terminal of the mixing amplifier unit serves as the output terminal of the low-noise down-converter, the mixing amplifier unit provides a reference signal to the phase-locked loop through the reference terminal, and the mixing amplifier unit is used to convert the high-frequency signal into an intermediate-frequency signal. The MCU is connected to the phase-locked loop, and the MCU is also used to control the local oscillator frequency of the phase-locked loop.
2. The low noise downconverter of claim 1, wherein, The dual-channel switching unit includes a first channel subunit, a second channel subunit, a power controller, a first low-dropout regulator, and a combiner; The first channel subunit includes two first LNAs and at least one second LNA, with the second LNA connected between the two first LNAs; The second channel subunit includes two first LNAs and at least one second LNA, with the second LNA connected between the two first LNAs; The output terminal of the power controller is connected to the enable terminal of the first LNA, and the power controller is used to provide an enable signal to the first LNA. The MCU is connected to the enable terminal of the second LNA in the first channel subunit and the second LNA in the second channel subunit through different first low dropout voltage regulators. The MCU is used to control the working state of the second LNA. The two input terminals of the combiner are respectively connected to the amplified signals output by the first channel subunit and the second channel subunit. The output terminal of the combiner is connected to the input terminal of the first bandpass filter. The combiner is used to combine multiple received signals into one signal and output it.
3. The low noise downconverter of claim 2, wherein, In the case where there are multiple second LNAs in the first channel subunit and / or the second channel subunit, the enable terminals of the multiple second LNAs located in the same signal channel are all connected to the same first low dropout regulator.
4. The low noise downconverter of claim 2, wherein, In the case where there are multiple second LNAs in the first channel subunit and / or the second channel subunit, the enable terminal of any second LNA in the same subunit is connected to the first low dropout regulator, and the enable terminals of other second LNAs in the same signal channel are connected to the power controller.
5. The low noise downconverter of claim 1 or 2, wherein, The mixing and amplification unit includes a mixer, a variable gain amplifier, a low-pass filter, an intermediate frequency amplifier, an intermediate frequency multiplexer, and a second band-pass filter. The first input terminal of the mixer is connected to the output terminal of the first bandpass filter, the second input terminal of the mixer is connected to the output terminal of the phase-locked loop, and the output terminal of the mixer is connected to the input terminal of the variable gain amplifier. The output terminal of the variable gain amplifier is connected to the input terminal of the low-pass filter, and the bias terminal of the variable gain amplifier is connected to the MCU so that the gain of the variable gain amplifier can be controlled by the MCU. The input terminal of the intermediate frequency amplifier is connected to the output terminal of the low-pass filter, and the output terminal of the intermediate frequency amplifier is connected to the input terminal of the intermediate frequency multiplexer. The first output terminal of the intermediate frequency multiplexer serves as the output terminal of the mixer amplification unit, and the second output terminal of the intermediate frequency multiplexer is connected to the input terminal of the second band-pass filter through a first capacitor. The output terminal of the second band-pass filter serves as the reference terminal of the mixer amplification unit and is connected to the input terminal of the phase-locked loop. The intermediate frequency multiplexer is used to select the frequency of the incoming signal and output it to the corresponding path.
6. The low noise downconverter of claim 5, wherein, The intermediate frequency multiplexer includes a first inductor and a second capacitor. The first end of the second capacitor is connected to the output terminal of the intermediate frequency amplifier, and the second end of the second capacitor serves as the output terminal of the mixing amplifier unit. The first end of the first inductor is connected to the second end of the second capacitor, and the second end of the first inductor is connected to the first capacitor.
7. The low-noise downconverter according to claim 5, characterized in that, The MCU is connected to the bias terminal of the variable gain amplifier through a resistor unit. The DAC voltage provided by the MCU is twice the voltage-controlled voltage of the variable gain amplifier. The resistor unit is used to divide the DAC voltage according to a preset ratio, which is 0.
5.
8. The low noise downconverter of claim 1, wherein, It also includes a DC-DC converter and a second low-dropout regulator. The input terminal of the DC-DC converter is connected to the voltage output terminal of the mixer amplifier unit. The DC-DC converter is used to output the first operating voltage required by the low-noise downconverter. The input terminal of the second low-dropout regulator is connected to the output terminal of the DC-DC converter, and the output terminal of the second low-dropout regulator is connected to the MCU. The second low-dropout regulator is used to provide a second operating voltage to the MCU.
9. The low noise downconverter of claim 1, wherein, It also includes an RS422 transceiver, which is connected to the MCU. The MCU is used to receive frequency parameters through the RS422 transceiver to adjust the local oscillator frequency of the phase-locked loop and to receive control signals through the RS422 transceiver to control the on or off of the signal channels in the dual-channel switching unit.
10. A transceiver, characterized by Includes the low-noise downconverter as described in any one of claims 1-9.