CN212410882U - Detection circuit of handheld millimeter wave detector - Google Patents
Detection circuit of handheld millimeter wave detector Download PDFInfo
- Publication number
- CN212410882U CN212410882U CN202020990364.XU CN202020990364U CN212410882U CN 212410882 U CN212410882 U CN 212410882U CN 202020990364 U CN202020990364 U CN 202020990364U CN 212410882 U CN212410882 U CN 212410882U
- Authority
- CN
- China
- Prior art keywords
- millimeter wave
- circuit
- power supply
- detector
- voltage
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Landscapes
- Radar Systems Or Details Thereof (AREA)
Abstract
The utility model discloses a detection circuit of a handheld millimeter wave detector, which consists of a millimeter wave transceiving front-end circuit, a digital acquisition and transmission circuit and a power system circuit; the millimeter wave transceiving front-end circuit comprises a millimeter wave emission source, a millimeter wave detector, a millimeter wave panel antenna and a secondary voltage-stabilizing conversion power supply; the digital acquisition and transmission circuit comprises a detection signal input interface, a video amplifier, an analog-to-digital conversion circuit, an MCU, a key input module, a signal indicator lamp module, an audio output module and an LCD display screen; the power supply system circuit comprises a power supply charging conversion circuit, a power supply management circuit and a voltage boosting and reducing circuit. The utility model adopts the integrated circuit to replace the traditional waveguide structure, has simple structure, reduces the volume and enhances the stability of the millimeter wave emission source during working; the digital acquisition and transmission circuit adopts a modular design, and all subsystems are integrated on one PCB, so that the size is small, the maintenance cost is low, and the upgrading difficulty is low.
Description
Technical Field
The utility model relates to a public safety field specifically is a detection circuitry of hand-held type millimeter wave detector.
Background
The inspection speed of the handheld millimeter wave security inspection instrument is almost the same as that of a handheld metal detector, the handheld millimeter wave security inspection instrument is matched with a millimeter wave imaging detection security inspection door for use, all articles carried by a human body can be inspected better and faster, the huge potential safety hazard existing when the existing metal security inspection door and the handheld metal detector are taken as personnel security inspection means is fundamentally solved, the handheld millimeter wave security inspection instrument is a development trend of the international personnel security inspection field, the replacement of the existing metal detection security inspection system is realized within a period in the future, and the handheld millimeter wave security inspection instrument is a necessary technical means in all places needing security inspection, such as the current civil aviation airport, stations, wharfs, important government facilities, courts, prisons, guard houses, customs frontiers, special public facilities, large-scale activities and the like, and.
The existing millimeter wave detector has poor circuit stability, uses a gunn millimeter wave source and a single horn antenna at the transceiving front end, has many defects, and is basically not used in the market at present; the digital acquisition and transmission circuit has poor integration level, the data processing algorithm is not perfect, certain problems exist, and the resolution capability to non-metallic substances is poor.
SUMMERY OF THE UTILITY MODEL
The utility model aims at providing a detection circuitry of hand-held type millimeter wave detector to solve the problem that proposes among the above-mentioned background art.
In order to achieve the above object, the utility model provides a following technical scheme:
a detection circuit of a handheld millimeter wave detector comprises a millimeter wave transceiving front-end circuit, a digital acquisition and transmission circuit and a power system circuit;
the millimeter wave transceiving front-end circuit comprises a millimeter wave emission source, a millimeter wave detector, a millimeter wave panel antenna and a secondary voltage-stabilizing conversion power supply;
the digital acquisition and transmission circuit comprises a detection signal input interface, a video amplifier, an analog-to-digital conversion circuit, an MCU, a key input module, a signal indicator lamp module, an audio output module and an LCD display screen;
the power system circuit comprises a power charging conversion circuit, a power management circuit and a voltage boosting and reducing circuit.
As an optimization of the present invention, the transmission frequency f of the millimeter wave transmission sourceTThe frequency is 77-80 GHz, and the transmitting output power is more than or equal to 18 dBm; the frequency stability is less than or equal to 100 KHz; the power stability is ± 1 dB.
Preferably, the sensitivity of the millimeter wave detector is 2.6-6V/mW; the output signal is in the form of a negative signal; the output interface is SMA.
Preferably, the antenna gain of the millimeter wave panel antenna is more than or equal to 20 dBi; the 3dB wave beam width of the antenna is less than or equal to 6 degrees; the polarization mode is linear polarization; the focal distance range is 3-20 cm; the volume was 110mm by 100mm by 30 mm.
As the utility model discloses a preferred, secondary steady voltage switching power supply's input voltage is +12V direct current voltage to produce +6V 0.1V and +3.3V 0.1V direct current voltage output through the conversion voltage conversion module, secondary steady voltage switching power supply ripple is less than or equal to 1%.
As the utility model discloses a preferred, detection signal input interface connection wave detector, and the wave detector produces the input signal that frequency is 1KHz, the duty cycle is 10%, voltage amplitude is 3V to millimeter wave receiving and dispatching front end circuit.
As the utility model discloses a preferred, millimeter wave receiving and dispatching front end circuit still includes the wave filter, and the wave filter includes hardware filtering and software filtering.
As the utility model discloses a preferred, power conversion circuit that charges passes through power adapter and connects the power, and input voltage when the power charges is 9V or 12V.
Compared with the prior art, the beneficial effects of the utility model are that:
1. the receiving and transmitting front-end circuit of the utility model adopts an integrated circuit to replace the traditional waveguide structure, has simple structure and reasonable design, reduces the volume and enhances the stability of the millimeter wave emission source during working; the digital acquisition and transmission circuit adopts a modular design, and all subsystems are integrated on one PCB, so that the cost is low, the volume is small, the maintenance cost is low, and the upgrading difficulty is low.
2. The transmission front end of the handheld millimeter wave detector has large transmission power, high frequency stability and long detection distance, the internal circuit of the handheld millimeter wave detector adopts a full integrated circuit, and each selected integrated chip has small volume and reliable performance; the receiving and transmitting channels are separated, so that the isolation between the receiving and transmitting channels is high, and the influence of local oscillator leakage on the stability of the whole machine is reduced.
Drawings
Fig. 1 is a schematic diagram of a middle millimeter wave transceiver front-end circuit according to the present invention;
FIG. 2 is a schematic diagram of the detection of the detector of the present invention;
FIG. 3 is a schematic diagram of the MCU circuit of the present invention;
FIG. 4 is a circuit diagram of the AD sampling and operational amplifier of the present invention;
fig. 5 is a schematic diagram of the FRAM LCD interface circuit of the present invention;
FIG. 6 is a schematic diagram of a power supply circuit of the digital system of the present invention;
fig. 7 is a schematic diagram of a low-pass filter circuit according to the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.
A detection circuit of a handheld millimeter wave detector comprises a millimeter wave transceiving front-end circuit, a digital acquisition and transmission circuit and a power system circuit;
the millimeter wave transceiving front-end circuit comprises a millimeter wave emission source, a millimeter wave detector, a millimeter wave panel antenna and a secondary voltage-stabilizing conversion power supply;
the digital acquisition and transmission circuit comprises a detection signal input interface, a video amplifier, an analog-to-digital conversion circuit, an MCU, a key input module, a signal indicator lamp module, an audio output module and an LCD display screen;
the power system circuit comprises a power charging conversion circuit, a power management circuit and a voltage boosting and reducing circuit.
In this embodiment, the transmission frequency f of the millimeter wave transmission sourceTThe frequency is 77-80 GHz, and the transmitting output power is more than or equal to 18 dBm; the frequency stability is less than or equal to 100 KHz; the power stability is ± 1 dB.
In the embodiment, the sensitivity of the millimeter wave detector is 2.6-6V/mW; the output signal is in the form of a negative signal; the output interface is SMA.
In this embodiment, the antenna gain of the millimeter wave panel antenna is greater than or equal to 20 dBi; the 3dB wave beam width of the antenna is less than or equal to 6 degrees; the polarization mode is linear polarization; the focal distance range is 3-20 cm; the volume was 110mm by 100mm by 30 mm.
In this embodiment, the input voltage of the secondary voltage stabilization conversion power supply is +12V dc voltage, and the +6V ± 0.1V and +3.3V ± 0.1V dc voltage outputs are generated by the conversion voltage conversion module, and the ripple of the secondary voltage stabilization conversion power supply is less than or equal to 1%.
In this embodiment, the detection signal input interface is connected to a detector, and the detector generates an input signal having a frequency of 1KHz, a duty ratio of 10%, and a voltage amplitude of 3V for the millimeter wave transceiver front-end circuit.
In this embodiment, the millimeter wave transceiver front-end circuit further includes a filter, and the filter includes hardware filtering and software filtering.
In this embodiment, the power charging conversion circuit is connected to a power supply through a power adapter, and the input voltage of the power charging conversion circuit is 9V or 12V.
In a specific using process, the power supply management circuit and the voltage boosting and reducing circuit undertake detection of the working state of the power supply, prevent abnormal conditions such as overvoltage and overcurrent from occurring in the circuit, and simultaneously convert the voltage output by the power supply into working voltage which can be used by a digital acquisition and transmission circuit and a millimeter wave transceiving front end circuit.
In a specific use process, the video amplifier amplifies and shapes the voltage quantity of the analog signal output by the detector.
In a specific use process, the analog-to-digital conversion circuit converts the amplified and shaped analog voltage quantity into digital quantity for output, and performs 16-bit analog-to-digital conversion with the sampling rate of 1M/s.
In a specific use process, the MCU selects an STM32F207VCT6, an ARM core, a 32-bit processor, the highest main frequency of 120MHz and a built-in 1M flash memory.
In a specific using process, the key input module performs power-on detection and setting of related parameters.
In a specific using process, the audio output module alarms the suspicious articles.
In a specific using process, the LCD display screen mainly displays related information and sets a threshold value of a detected sample.
In this embodiment, the millimeter wave transceiver front-end circuit further includes a data acquisition and signal processing module.
In the specific use process, the millimeter wave emission source is composed of circuits such as a crystal oscillator, a phase-locked loop, a frequency multiplier, a frequency mixer, an amplifier and the like. The method comprises the steps of generating a 9.625GHz signal through a crystal oscillator, a phase-locked loop and a VCO, generating a 77GHz signal through octave, adding a 1KHz square wave modulation signal through a frequency mixer, finally generating a 77GHz AM-modulated millimeter wave signal with the power of more than or equal to 25dBm through a PA, connecting all feed sources on a microstrip line and a panel antenna, and transmitting the millimeter wave signal. When a signal emitted by the millimeter wave emission source is radiated to a measured object, the measured object reflects a part of millimeter wave signals, and the +12VDC is added to the low-noise amplifier, so that the detection sensitivity is 2.6-6V/mW; detecting the distance: 0.1-5 m; probe response time: 1-3 seconds.
In the specific use process, a transmitting antenna and a receiving antenna in the millimeter wave panel antenna are separated, the antenna is an array panel antenna, the beam width is less than 6 degrees, the antenna G is more than or equal to 20dB, the adopted polarization mode is linear polarization, the transmitting and receiving frequencies of the antenna are 77 GHz-80 GHz, and the microstrip line is connected with a transmitting source and a receiving detector.
In the specific use process, the secondary voltage-stabilizing conversion power supply inputs +12V direct-current voltage and generates +6V +/-0.1V and +3.3V +/-0.1V direct-current voltage through the LM7805 conversion circuit to be output, the load current is between 1A and 2A, and the ripple wave of the secondary voltage-stabilizing conversion power supply is less than or equal to 1 percent.
In a specific using process, a received millimeter wave signal is input to a detector, the detector converts the detected millimeter wave signal into a direct current signal and inputs the direct current signal into a low-pass filter, other high-frequency components may exist in a 1KHz signal detected by the detector, in order to ensure the accuracy and stability of signal detection, a low-pass filter is further required to be loaded at the rear end of the detector, and specific indexes of the low-pass filter are as follows:
cutting to frequency (f)p)：1KHz；
② stop band upper limit frequency (f)s)：2KHz；
③ inner ripple (A)p)：1dB；
(iv) stop band attenuation (A)s)：40dB。
In the specific use process, the digital acquisition and transmission circuit further comprises a low-pass filter and an AD sampling and operational amplification circuit, the low-pass filter filters out interference signals on direct current signals, the signals are input to the AD sampling and operational amplification circuit, an interface connected with the MCU is provided, and the MCU can realize gain control of operational amplifier and related work of ADC data acquisition.
In the specific use process, the LCD display screen is mainly used for displaying the acquired voltage signal value and the corresponding AD value, and due to the fact that real-time detection is carried out, the voltage value has corresponding jump, and the speed regulating button can control the speed of digital jump. Different detection materials are also different in echo voltage value transmitted back through millimeter waves and can be correspondingly distributed in a certain voltage interval. Through the threshold setting button, the AD threshold of the labeled sample calibrated through the experiment can be input in advance. The AD threshold values of the same sample in different containers are different, so that the corresponding upper and lower threshold values are input respectively.
In a specific use process, the digital acquisition and transmission circuit further comprises an FRAMLCD interface, wherein FRAM is used for storing a large standard sample database which needs to be calibrated later, and an LCD is used for displaying the detection result. The currently selected LCD size is 3.5 "LCD screen.
In a specific use process, the digital acquisition and transmission circuit further comprises a digital system power supply circuit, the outside of the digital acquisition module needs voltage of 9-13V for power supply and then is converted into two voltages of 3.3V and 5V which are respectively used as power supply voltages of chips such as an AD (analog-to-digital) chip, an operational amplifier chip, an MCU (microprogrammed control unit) chip and the like.
In a specific use process, a low-noise preamplifier is adopted in a millimeter wave receiving channel to amplify a received weak signal, so that the detection sensitivity of the detector is improved, and the accuracy of the detector in detecting a detected object is greatly improved;
in a specific use process, the millimeter wave panel antenna adopts the array panel antenna, so that the design is reasonable, the structure is simple, the volume is reduced, and the stability of the millimeter wave emission source during working is enhanced;
in the specific use process, the digital acquisition and transmission circuit adopts a modular design, and all subsystems are concentrated on one PCB, so that the whole handheld millimeter wave detector has the advantages of high integration level, low cost, small volume, low maintenance cost and low upgrading difficulty.
The foregoing shows and describes the general principles, essential features, and advantages of the invention. It should be understood by those skilled in the art that the present invention is not limited by the above embodiments, and the description in the above embodiments and the description is only preferred examples of the present invention, and is not intended to limit the present invention, and that the present invention can have various changes and modifications without departing from the spirit and scope of the present invention, and these changes and modifications all fall into the scope of the claimed invention. The scope of the invention is defined by the appended claims and equivalents thereof.
Claims (8)
1. The detection circuit of the handheld millimeter wave detector is characterized in that: the device consists of a millimeter wave transceiving front-end circuit, a digital acquisition and transmission circuit and a power system circuit;
the millimeter wave transceiving front-end circuit comprises a millimeter wave emission source, a millimeter wave detector, a millimeter wave panel antenna and a secondary voltage-stabilizing conversion power supply;
the digital acquisition and transmission circuit comprises a detection signal input interface, a video amplifier, an analog-to-digital conversion circuit, an MCU, a key input module, a signal indicator lamp module, an audio output module and an LCD display screen;
the power system circuit comprises a power charging conversion circuit, a power management circuit and a voltage boosting and reducing circuit.
2. The detection circuit of the hand-held millimeter wave detector of claim 1, characterized in that: the transmission frequency f of the millimeter wave emission sourceTThe frequency is 77-80 GHz, and the transmitting output power is more than or equal to 18 dBm; the frequency stability is less than or equal to 100 KHz; the power stability is ± 1 dB.
3. The detection circuit of the hand-held millimeter wave detector of claim 1, characterized in that: the sensitivity of the millimeter wave detector is 2.6-6V/mW; the output signal is in the form of a negative signal; the output interface is SMA.
4. The detection circuit of the hand-held millimeter wave detector of claim 1, characterized in that: the antenna gain of the millimeter wave panel antenna is more than or equal to 20 dBi; the 3dB wave beam width of the antenna is less than or equal to 6 degrees; the polarization mode is linear polarization; the focal distance range is 3-20 cm; the volume was 110mm by 100mm by 30 mm.
5. The detection circuit of the hand-held millimeter wave detector of claim 1, characterized in that: the input voltage of the secondary voltage stabilization conversion power supply is +12V direct-current voltage, the +6V +/-0.1V and +3.3V +/-0.1V direct-current voltage output is generated through the conversion voltage conversion module, and the ripple wave of the secondary voltage stabilization conversion power supply is less than or equal to 1%.
6. The detection circuit of the hand-held millimeter wave detector of claim 1, characterized in that: the detection signal input interface is connected with a detector, and the detector generates an input signal with the frequency of 1KHz, the duty ratio of 10% and the voltage amplitude of 3V for the millimeter wave transceiving front end circuit.
7. The detection circuit of the hand-held millimeter wave detector of claim 1, characterized in that: the millimeter wave transceiving front-end circuit further comprises a filter, and the filter comprises hardware filtering and software filtering.
8. The detection circuit of the hand-held millimeter wave detector of claim 1, characterized in that: the power supply charging conversion circuit is connected with a power supply through a power supply adapter, and the input voltage of the power supply during charging is 9V or 12V.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202020990364.XU CN212410882U (en) | 2020-06-03 | 2020-06-03 | Detection circuit of handheld millimeter wave detector |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202020990364.XU CN212410882U (en) | 2020-06-03 | 2020-06-03 | Detection circuit of handheld millimeter wave detector |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN212410882U true CN212410882U (en) | 2021-01-26 |
Family
ID=74408727
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202020990364.XU Active CN212410882U (en) | 2020-06-03 | 2020-06-03 | Detection circuit of handheld millimeter wave detector |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN212410882U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116346255A (en) * | 2023-05-30 | 2023-06-27 | 航宇伟创科技(北京)有限公司 | Radio station one-line detector detection circuit |
-
2020
- 2020-06-03 CN CN202020990364.XU patent/CN212410882U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116346255A (en) * | 2023-05-30 | 2023-06-27 | 航宇伟创科技(北京)有限公司 | Radio station one-line detector detection circuit |
| CN116346255B (en) * | 2023-05-30 | 2023-08-08 | 航宇伟创科技(北京)有限公司 | Radio station one-line detector detection circuit |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN1906500B (en) | Compact-size, low-power-consumption, short pulse radar and its control method | |
| US10237765B1 (en) | Passive intermodulation (PIM) measuring instrument and method of measuring PIM | |
| CN110350932A (en) | A kind of high-frequency wideband receiver and signal processing method | |
| CN108535540B (en) | Method for instantaneously measuring transmitting frequency of magnetron radar | |
| CN103869306B (en) | Metal and Nonlinear Parameter composite detecting device | |
| CN212410882U (en) | Detection circuit of handheld millimeter wave detector | |
| US20190302230A1 (en) | Method and system using tr assembly to obtain intermediate-frequency controllable signal | |
| CN104993887A (en) | Integrated pulse state noise factor test method and tester | |
| CN108254745B (en) | Radio frequency microwave system applied to radar detection of water-float plants | |
| CN102307071A (en) | Portable broadcast monitoring receiver | |
| CN111064480B (en) | Broadband signal generating device | |
| CN114609593B (en) | Harmonic radar based on FPGA and deep learning | |
| CN201197142Y (en) | Satellite beacon receiver | |
| CN205071007U (en) | Handheld radio comprehensive tester | |
| CN106353740A (en) | Radio responding calibration equipment based on time sequence pulse encoding | |
| CN102904588A (en) | Ku band receiver for satellites | |
| CN213689981U (en) | Terahertz security inspection device with eddy current effect | |
| CN209928031U (en) | Portable 2.4G nonlinear node detection system | |
| CN210781075U (en) | Ku-waveband high-speed video demodulation receiver | |
| CN109270533A (en) | A kind of airpark foreign bodies detection radar system and method | |
| CN215818173U (en) | Electronic interference device | |
| CN101877617A (en) | Portable wireless monitor | |
| CN202094901U (en) | Emission port standing wave detection and automatic fitting module | |
| CN203661073U (en) | Reverse noise monitoring apparatus and reverse optical receiver | |
| CN114167241A (en) | High-frequency current partial discharge signal monitoring method, sensing device and partial discharge monitoring system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |