CN210609134U

CN210609134U - Unmanned aerial vehicle frequency channel receiver

Info

Publication number: CN210609134U
Application number: CN201922001970.4U
Authority: CN
Inventors: 钟为金; 徐克兴; 谭尊林
Original assignee: Dfine Technology Co Ltd
Current assignee: Dfine Technology Co Ltd
Priority date: 2019-11-19
Filing date: 2019-11-19
Publication date: 2020-05-22
Anticipated expiration: 2029-11-19

Abstract

The utility model discloses an unmanned aerial vehicle frequency band receiver, which comprises a signal amplification unit, a frequency converter, a main control unit and a monitor which are connected in sequence; the main control unit is provided with a main chip which is mutually connected with the frequency converter; the signal amplification unit realizes the suppression of out-of-band interference signals through a low-noise filter and a band-pass filter, the frequency converter receives radio-frequency signals output by the signal amplification unit for frequency conversion and outputs intermediate-frequency signals to the main control unit, and the frequency converter and the main control unit realize the suppression of radio-frequency and local oscillator leakage signals and out-of-band useless signals in the intermediate-frequency signals through a low-pass filter and an acoustic meter filter which are sequentially connected, so that the receiving sensitivity of the receiver is ensured; the main control unit outputs video data to a monitor according to the intermediate frequency signal; therefore, stable video information transmission is realized, an external local vibration source is not needed, the space of the PCB is saved, the radio frequency debugging difficulty is reduced, and the manufacturability of the product is increased.

Description

Unmanned aerial vehicle frequency channel receiver

Technical Field

The utility model relates to a radio frequency receives the field, especially relates to an unmanned aerial vehicle frequency channel receiver.

Background

In the existing unmanned aerial vehicle receiver on the market, the receiving frequency is different according to different system settings, and the receiving sensitivity difference is large; in the aspects of frequency band transmission application in multiple fields such as unmanned aerial system downlink telemetering and information transmission links, police unmanned aerial vehicles and helicopter video transmission (1430 + 1438 MHz), civil unmanned aerial vehicles and helicopter video transmission (1438 + 1444 MHz), professional video transmission, emergency communication system video transmission and the like, the radio frequency identification device often contains more out-of-band interference signals, the video transmission stability is poor, the receiving sensitivity of a receiver is generally low, the production cost is high, the radio frequency debugging difficulty is high, and the SPI data configuration is troublesome.

SUMMERY OF THE UTILITY MODEL

The utility model aims to solve the problems, and provides an unmanned aerial vehicle frequency band receiver which comprises a signal amplification unit, a frequency converter, a main control unit and a monitor which are connected in sequence; the main control unit is provided with a main chip which is mutually connected with the frequency converter; the frequency converter receives the radio frequency signal output by the signal amplification unit for frequency conversion, and outputs an intermediate frequency signal to the main control unit, and the main control unit outputs video data to the monitor according to the intermediate frequency signal.

Furthermore, the signal amplification unit comprises a first band-pass filter, two cascaded low-noise amplifiers and a second band-pass filter which are sequentially connected in series.

Further, the frequency converter is an active down converter.

Furthermore, a low-pass filter, a sound meter filter and an intermediate frequency low noise amplifier are sequentially connected in series between the active down converter and the main control unit, the low-pass filter suppresses signals leaked by radio frequency and a local oscillator, and the sound meter filter suppresses out-of-band useless signals, so that the receiving sensitivity of the receiver is ensured.

Furthermore, an IPEX seat is arranged between the intermediate-frequency low-noise amplifier and the main control unit, and the IPEX seat can realize compatibility with emergency communication products in the 36-1002 MHz wave band.

Furthermore, an ARM is arranged in the main chip, and the ARM configures the SPI data of the active down converter.

Further, the antenna system is connected with the signal amplification unit and used for sending the radio-frequency signal to the signal amplification unit.

The utility model has the advantages that: by adopting the active integrated frequency mixing frequency converter, the frequency spectrum from the radio frequency to the intermediate frequency can be directly moved without an external local vibration source, the space of a PCB (printed circuit board) is saved, the radio frequency debugging difficulty is reduced, and the manufacturability of a product is increased.

SPI data configuration of the active mixer can be realized through an ARM external extension pin arranged in a main chip, and single chip configuration does not need to be added; the system can be quickly transformed into an unmanned aerial vehicle receiver product under the condition of being compatible with the original emergency broadcast product; compared with the products on the market at present, the frequency validity is higher, the receiving sensitivity is higher, and the production is easier.

Drawings

Fig. 1 is a schematic diagram of a connection of an unmanned plane frequency band receiver;

fig. 2 is a schematic diagram of a structure and a flow of an unmanned plane frequency band receiver;

fig. 3 is a connection diagram of a baseband part circuit IPEX socket of an unmanned aerial vehicle frequency band receiver.

Detailed Description

In order to clearly understand the technical features, objects, and effects of the present invention, embodiments of the present invention will be described with reference to the accompanying drawings.

As shown in fig. 1, an unmanned aerial vehicle frequency band receiver includes a main control unit and a signal amplification unit connected to the main control unit through an active down converter; the active down converter receives the radio frequency signal output by the signal amplification unit to carry out frequency conversion, namely frequency spectrum shifting, and then outputs an intermediate frequency signal to the main control unit, and the main control unit outputs video data to the monitor according to the intermediate frequency signal so as to realize the receiving of the video signal of the unmanned aerial vehicle.

In this embodiment, the active down converter is an active mixer HMC1190LP6GE, and due to the introduction of the active down converter, noise (noise coefficient may be as high as 9 dB) is inevitably introduced, thereby reducing the receiving sensitivity of the system; in order to improve the receiving sensitivity of the system and ensure the normal work of the active down converter, the frequency spectrum from the radio frequency to the intermediate frequency is moved without an external local vibration source; two cascaded low-noise amplifiers are required to be introduced at the front end of radio frequency, the low-noise amplifier is SPF-5043Z, and two stages of band-pass filters are selected simultaneously, wherein the band-pass filters are BFCN-1445 +; the low noise amplifier and the band-pass filter jointly realize the suppression of out-of-band interference signals, so that the purity of a received frequency spectrum is ensured.

Because the active down converter can shift the frequency spectrum of the radio frequency signal, two useless signals of radio frequency and local oscillator are inevitably generated, and although the isolation degree of the radio frequency port of the HMC1190LP6GE to the middle frequency port is as high as 46dB, the isolation degree is not enough for a system with high receiving sensitivity.

Because the main suppression frequency is radio frequency and local oscillation, a low-pass filter LFCN-320+ is introduced at the intermediate frequency output end to ensure the leakage suppression degree; finally, an acoustic surface filter HDJ1765A1-S4 is introduced to ensure that the suppression degree of other unwanted signals outside the band is high enough, such as power supply noise, crystal oscillator and other low-frequency frequencies.

As shown in fig. 2, the main control unit includes a main chip and RJ45, UART, USB, IR, SPI Flash, NAND Flash, and DDR3 interfaces; the system comprises an RJ45, a UART, a USB, an infrared receiver, an SPI Flash, a NAND Flash, a DDR3, a network interface, a host chip, a USB, a system program and the like, wherein the RJ45 is used for debugging programs and can be expanded to form network interface video stream output, the UART is used for printing work information of the host chip, the USB can be expanded to store local videos, the IR is used for infrared reception, the SPI Flash is used.

The main chip is used for channel decoding and video decoding, and the built-in ARM can be configured with the SPI data of the active down converter.

The main control unit also comprises an HDMI interface connected with the monitor and used for outputting audio and video data to the monitor.

After the radio frequency signal is input, the radio frequency signal firstly passes through a first band-pass filter BFCN-1445+ of the signal amplifying unit, and the effective bandwidth is as follows: 50MHz, insertion loss: 3 dB; then enters the LNA1, i.e. two cascaded rf low noise amplifiers SPF-5043Z, with a gain of: 15dB, the radio frequency signal enters a second band-pass filter after being output, and then is output to an active down converter, the active down converter is HMC1190LP6GE, and the radio frequency input frequency band is: 700-3500MHz, the intermediate frequency output frequency range is: 50-350MHz, the noise figure is: 9dB, gain is: 8 dB.

The active down converter completes the spectrum shift from radio frequency to intermediate frequency through the down conversion chip, and then outputs the intermediate frequency signal to the low pass filter LFCN-320+ so as to ensure the leakage suppression system, and the insertion loss is as follows: 1.2 dB; finally, a sound table filter HDJ1765A1-S4 is introduced to ensure that the suppression degree of other unwanted signals outside the band is high enough; LNA2 is an intermediate frequency low noise amplifier.

The active down converter has the main function of completing the spectrum shift of the original 36-1002 MHz wave band, so that the frequency range specified by the Ministry of industry and communications on the unmanned aircraft system can be reached; the radio frequency signal enters a receiver through an antenna feed system, passes through a first band-pass filter, is amplified through a two-stage radio frequency low noise amplifier, and then enters a down-conversion chip through a second band-pass filter. And the intermediate frequency signal subjected to frequency spectrum shifting by the down-conversion chip is subjected to primary low pass to suppress the signals leaked by radio frequency and a local oscillator, and finally, the out-of-band useless signals are suppressed again by the acoustic meter filter to ensure the receiving sensitivity of the out-of-band useless signals.

The SPI data configuration of the active down converter is completed by a main chip of an internal integrated ARM, and a single chip microcomputer is not required to be added, so that the structure of the active down converter is simplified, and the active down converter is convenient to produce and maintain.

As shown in fig. 3, the circuit design of the baseband part of the main control unit is basically unchanged because the frequency band receiver of the unmanned aerial vehicle is compatible with the emergency communication product in the original 36-1002 MHz band.

An IPEX seat is compatibly designed at the input front section of the LNA2 intermediate frequency low noise amplifier, the default is NC, when the original 36-1002 MHz waveband product is required to be used, the coupling capacitor end at the front end of the IPEX seat can be disconnected, the IPEX seat is welded, an IPEX-SMA patch cord is directly connected to the seat, and the production is very convenient.

The utility model discloses an active down converter realizes moving radio frequency signal's frequency spectrum, realizes restraining the interfering signal of outband through low noise filter and band pass filter simultaneously, utilizes low pass filter and sound meter filter to restrain radio frequency and local oscillator leakage signal and outband unnecessary signal to the sensitivity of receipt of guarantee receiver realizes stable video information transmission.

The basic principles and the main features of the invention and the advantages of the invention have been shown and described above. It will be understood by those skilled in the art that the present invention is not limited to the above embodiments, and that the foregoing embodiments and descriptions are provided only to illustrate the principles of the present invention without departing from the spirit and scope of the present invention. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims

1. An unmanned aerial vehicle frequency band receiver is characterized by comprising a signal amplification unit, a frequency converter, a main control unit and a monitor which are sequentially connected; the main control unit is provided with a main chip which is mutually connected with the frequency converter; the frequency converter receives the radio frequency signal output by the signal amplification unit for frequency conversion, and outputs an intermediate frequency signal to the main control unit, and the main control unit outputs video data to the monitor according to the intermediate frequency signal.

2. The frequency band receiver of claim 1, wherein the signal amplification unit comprises a first band-pass filter, two cascaded low noise amplifiers and a second band-pass filter, which are connected in series in sequence.

3. The drone frequency band receiver of claim 1, wherein the frequency converter is an active down converter.

4. The unmanned aerial vehicle frequency band receiver of claim 3, wherein a low pass filter, a sound meter filter and an intermediate frequency low noise amplifier are further sequentially connected in series between the active down converter and the main control unit, the low pass filter suppresses radio frequency and local oscillator leakage signals, and the sound meter filter suppresses out-of-band unwanted signals, thereby ensuring the receiving sensitivity of the receiver.

5. The unmanned aerial vehicle frequency band receiver of claim 4, wherein an IPEX seat is arranged between the intermediate frequency low noise amplifier and the main control unit, and the IPEX seat can be compatible with an emergency communication product in a 36-1002 MHz band.

6. The UAV band receiver of claim 1, wherein the main chip has an ARM built in, and the ARM configures the SPI data of the active down converter.

7. The frequency band receiver of claim 1, further comprising an antenna feed system, wherein the antenna feed system is connected to the signal amplification unit, and is configured to send the radio frequency signal to the signal amplification unit.