CN216056944U

CN216056944U - Low-noise amplifying circuit

Info

Publication number: CN216056944U
Application number: CN202121651475.9U
Authority: CN
Inventors: 李春; 宋磊; 谢成清; 高尔远; 袁勤
Original assignee: Shenzhen Aerospace Dongfanghong Satellite Co ltd
Current assignee: Shenzhen Aerospace Dongfanghong Satellite Co ltd
Priority date: 2021-07-20
Filing date: 2021-07-20
Publication date: 2022-03-15
Anticipated expiration: 2031-07-20

Abstract

The utility model provides a low-noise amplification circuit which comprises a low-noise amplifier, wherein a radio-frequency input end of the low-noise amplifier is electrically connected with an input filter circuit and then is connected with a radio-frequency signal, and a radio-frequency output end of the low-noise amplifier is electrically connected with a coupling capacitor C117 and a direct-current power supply and outputs the amplified radio-frequency signal. The utility model has the beneficial effects that: the gain amplification of the radio frequency signal (S frequency band) is realized, the circuit structure is simple, the miniaturization degree is high, the power consumption is low, and the problem that the satellite communication radio frequency front end in the prior art can not be well considered in low noise amplification and adaptation to a wider working frequency band is solved.

Description

Low-noise amplifying circuit

Technical Field

The utility model relates to a satellite communication system, in particular to a low-noise amplifying circuit.

Background

In the process of receiving and processing satellite communication and satellite navigation signals, particularly processing of smaller signals, amplification processing is required. In addition, the frequency range covered by the received satellite signals is also relatively large, so that when receiving the satellite communication signals with relatively small radio frequency amplitude, the satellite communication signals need to obtain relatively high amplification gain, but cannot introduce too high input noise, and simultaneously also need to meet the requirements of a relatively wide operating frequency band, and the existing amplification circuit at the radio frequency front end cannot simultaneously meet the requirements.

Disclosure of Invention

In order to solve the problems in the prior art, the utility model provides a low-noise amplification circuit, which solves the problem that the low-noise amplification and the wide-adaptation working frequency band of the satellite communication radio frequency front end cannot be considered well in the prior art.

The utility model provides a low-noise amplification circuit which comprises a low-noise amplifier, wherein a radio-frequency input end of the low-noise amplifier is electrically connected with an input filter circuit and then is connected with a radio-frequency signal, and a radio-frequency output end of the low-noise amplifier is electrically connected with a coupling capacitor C117 and a direct-current power supply and outputs the amplified radio-frequency signal.

As a further improvement of the utility model, the low noise amplifier is model TQP3M 9037.

As a further improvement of the present invention, the input filter circuit includes a first input filter capacitor C27 and a second input filter capacitor C116 connected in series, one end of the first input filter capacitor C27 is connected to a radio frequency signal, the other end is electrically connected to one end of the second input filter capacitor C116, and the other end of the second input filter capacitor C116 is electrically connected to a radio frequency input terminal RFI of the low noise amplifier; the first input filter capacitor C27 and the second input filter capacitor C116 are connected to the input filter inductor L38 and then grounded.

As a further improvement of the utility model, the dc power supply is connected with a power supply filter circuit, the power supply filter circuit includes a first power supply filter inductor L39, a current limiting resistor R8, and a second power supply filter inductor L37, one end of the first power supply filter inductor connected to L39 is connected to the dc power supply, and the other end is connected in series with the current limiting resistor R8 and the second power supply filter inductor L37 and then connected to the radio frequency output end RFO of the low noise amplifier; the current limiting resistor R8 is grounded after being connected with the power supply filter capacitor C114 between the second power supply filter inductor L37, and the current limiting resistor R8 is grounded after being connected with the power supply filter capacitor C115 between the second power supply filter inductor L37.

As a further improvement of the utility model, two of said low noise amplifiers are cascaded together.

As a further improvement of the present invention, an attenuation network is further disposed between the two low noise amplifiers, and the attenuation network includes a first resistor R11, a second resistor R13, and a third resistor R14; a first end of the first resistor R11 is connected to the coupling capacitor C117 and then connected to the rf output terminal RFO of the previous low noise amplifier, and a second end of the first resistor R11 is connected to the input filter circuit and then connected to the rf input terminal RFI of the next low noise amplifier; the first end of the first resistor R11 is also connected to the second resistor R13 and then grounded, and the second end of the first resistor R11 is also connected to the third resistor R14 and then grounded.

The utility model has the beneficial effects that: by the scheme, the gain amplification of the radio frequency signal (S frequency band) is realized, the circuit structure is simple, the miniaturization degree is high, the power consumption is low, and the problem that the satellite communication radio frequency front end in the prior art cannot well take account of low-noise amplification and adaptation to a wider working frequency band is solved.

Drawings

Fig. 1 is a schematic diagram of a low noise amplifier circuit of the present invention.

Fig. 2 is a schematic diagram of two low noise amplifiers of a low noise amplification circuit of the present invention cascaded together.

Detailed Description

The utility model is further described with reference to the following description and embodiments in conjunction with the accompanying drawings.

As shown in fig. 1, a low noise amplifier circuit includes a low noise amplifier TQP3M9037, and a radio frequency input RFI of the low noise amplifier TQP3M9037 is connected to an input filter circuit and then receives a radio frequency signal, which is an S-band signal (2 GHz-4 GHz). The rf output terminal RFO is electrically connected to the coupling capacitor C117 and the dc power supply 5V _ RX, and outputs an amplified rf signal.

The input filter circuit comprises a first input filter capacitor C27 and a second input filter capacitor C116 which are connected in series, one end of the first input filter capacitor C27 is connected with a radio frequency signal, the other end of the first input filter capacitor C27 is electrically connected with one end of the second input filter capacitor C116, and the other end of the second input filter capacitor C116 is electrically connected with a radio frequency input end RFI of a low noise amplifier TQP3M 9037; the electric connection part of the first input filter capacitor C27 and the second input filter capacitor C116 is also electrically connected with the input filter inductor L38 and then grounded. The input filter circuit firstly carries out filtering processing on the radio frequency signal, and then inputs the radio frequency signal into the low noise amplifier TQP3M9037 for low noise amplification.

Preferably, the NC terminals of the low noise amplifiers TQP3M9037 are all grounded, and the SD terminal is floating.

Preferably, the direct current power supply 5V _ RX is further electrically connected to a power supply filter circuit, the power supply filter circuit includes a first power supply filter inductor L39, a current limiting resistor R8, and a second power supply filter inductor L37, one end of the first power supply filter inductor L39 is electrically connected to the direct current power supply 5V _ RX, and the other end of the first power supply filter inductor L37 is connected in series to a current limiting resistor R8 and a radio frequency output end RFO of the low noise amplifier TQP3M 9037; the electric connection part of the current limiting resistor R8 and the second power supply filter inductor L37 is also electrically connected with two power supply filter capacitors (C114 and C115) and then grounded.

The dc power supply 5V _ RX is filtered by the first power filter inductor L39, the second power filter inductor L37, and the power filter capacitors (C114 and C115) to supply power to the low noise amplifier TQP3M 9037. The radio frequency output end RFO of the low noise amplifier TQP3M9037 outputs the filtered and amplified radio frequency signal, and is electrically connected to the coupling capacitor C117 and then transmitted to the next stage.

Fig. 2 is a combined view of another embodiment of the present invention. Two low noise amplifiers TQP3M9037 are cascaded together. An attenuation network is further arranged between the two low noise amplifiers TQP3M9037, and the attenuation network is used for performing signal attenuation and impedance conversion on the radio frequency signal output by the previous-stage low noise amplifier TQP3M9037 (U4 in fig. 2), and then inputting the radio frequency signal into the next-stage low noise amplifier TQP3M9037 (U12 in fig. 2) for low noise amplification.

The attenuation network comprises a first resistor R11, a second resistor R13 and a third resistor R14; a first end of the first resistor R11 is connected to the coupling capacitor C117 and then connected to the rf output terminal RFO of the previous low noise amplifier TQP3M9037 (U4 in fig. 2), and a second end of the first resistor R11 is connected to the input filter circuit and then connected to the rf input terminal RFI of the next low noise amplifier TQP3M9037 (U12 in fig. 2); the first end of the first resistor R11 is also connected to the second resistor R13 and then grounded, and the second end of the first resistor R11 is also connected to the third resistor R14 and then grounded.

Preferably, the rf input terminal of the next-stage low noise amplifier TQP3M9037 (U12 in fig. 2) is also connected to the input filter circuit, and the rf output terminal is also electrically connected to the coupling capacitor and the dc power supply 5V _ RX, and the circuit structure is consistent with the above description, and is not repeated here.

According to the utility model, the input radio frequency signal is filtered, and signal attenuation and impedance transformation are carried out after the first low-noise amplification, so that the noise coefficient of the radio frequency signal after the second low-noise amplification is less than 0.8 and the gain is greater than 45 dB.

Therefore, the utility model discloses a low-noise amplification circuit which comprises a low-noise amplifier TQP3M9037, wherein the radio-frequency input end of the low-noise amplifier TQP3M9037 is connected with an input filter circuit and then is connected with a radio-frequency signal, and the radio-frequency output end is electrically connected with a coupling capacitor and a direct-current power supply and outputs the amplified radio-frequency signal. The utility model realizes the gain amplification of the radio frequency signal (S frequency band), and has the advantages of simple circuit structure, high miniaturization degree and low power consumption.

The foregoing is a more detailed description of the utility model in connection with specific preferred embodiments and it is not intended that the utility model be limited to these specific details. For those skilled in the art to which the utility model pertains, several simple deductions or substitutions can be made without departing from the spirit of the utility model, and all shall be considered as belonging to the protection scope of the utility model.

Claims

1. A low-noise amplification circuit, characterized in that: the low-noise amplifier comprises a low-noise amplifier, wherein a radio frequency input end of the low-noise amplifier is electrically connected with an input filter circuit and then is connected with a radio frequency signal, and a radio frequency output end of the low-noise amplifier is electrically connected with a coupling capacitor C117 and a direct-current power supply and outputs the amplified radio frequency signal.

2. The low-noise amplification circuit according to claim 1, wherein: the model of the low noise amplifier is TQP3M 9037.

3. The low-noise amplification circuit according to claim 2, wherein: the input filter circuit comprises a first input filter capacitor C27 and a second input filter capacitor C116 which are connected in series, wherein one end of the first input filter capacitor C27 is connected with a radio frequency signal, the other end of the first input filter capacitor C27 is electrically connected with one end of the second input filter capacitor C116, and the other end of the second input filter capacitor C116 is electrically connected with a radio frequency input end RFI of the low noise amplifier; the first input filter capacitor C27 and the second input filter capacitor C116 are connected to the input filter inductor L38 and then grounded.

4. The low-noise amplification circuit according to claim 2, wherein: the direct current power supply is connected with a power supply filter circuit, the power supply filter circuit comprises a first power supply filter inductor L39, a current limiting resistor R8 and a second power supply filter inductor L37, one end of the first power supply filter inductor connected with the L39 is connected with the direct current power supply, and the other end of the first power supply filter inductor is connected with the current limiting resistor R8 and the second power supply filter inductor L37 in series and then is connected with a radio frequency output end RFO of the low noise amplifier; the current limiting resistor R8 is grounded after being connected with the power supply filter capacitor C114 between the second power supply filter inductor L37, and the current limiting resistor R8 is grounded after being connected with the power supply filter capacitor C115 between the second power supply filter inductor L37.

5. The low-noise amplification circuit according to claim 2, wherein: two of the low noise amplifiers are cascaded together.

6. The low-noise amplification circuit according to claim 5, wherein: an attenuation network is further arranged between the two low noise amplifiers, and the attenuation network comprises a first resistor R11, a second resistor R13 and a third resistor R14; a first end of the first resistor R11 is connected to the coupling capacitor C117 and then connected to the rf output terminal RFO of the previous low noise amplifier, and a second end of the first resistor R11 is connected to the input filter circuit and then connected to the rf input terminal RFI of the next low noise amplifier; the first end of the first resistor R11 is also connected to the second resistor R13 and then grounded, and the second end of the first resistor R11 is also connected to the third resistor R14 and then grounded.