Lateral two-beam vehicle-mounted Doppler speed radar equipment

Abstract

The present invention relates to a lateral two-beam Doppler speed measurement radar device, which mainly solves the problem that the prior art cannot simultaneously measure the forward speed and lateral speed of a vehicle and has low measurement accuracy. The device comprises: an antenna (1), a transceiver (2), a signal processing unit (3), and a power supply component (4). The transceiver generates a K-band continuous wave signal and enters a transmitting antenna. The transmitting antenna radiates an echo signal with a Doppler frequency shift to the ground. After receiving the echo signal, the receiving antenna enters the transceiver for amplification and orthogonal mixing, and outputs an orthogonal Doppler frequency shift signal. The signal processing unit samples the Doppler frequency shift signal, calculates the Doppler frequency shift through a frequency tracking algorithm, and combines the beam pointing angle information to calculate the radar forward speed and lateral speed. The present invention eliminates random errors caused by vehicle vibration and turbulence, reduces the speed measurement mean error, avoids cumulative errors, and can be used to measure the forward speed and lateral speed of a vehicle relative to the ground.

Description

Technical Field

[0001] The invention belongs to the field of radar technology, and in particular relates to a Doppler speed measuring radar, which can be used to measure the forward speed and lateral speed of a vehicle relative to the ground. Background Art

[0002] Common on-board speed measuring equipment is mainly odometers, which use the number of rotations of the vehicle's tires to directly measure the distance and speed of the vehicle on the ground. It is a mechanical speed measurement. Generally, the odometer is installed on the vehicle's drive shaft. When the vehicle is driving, it will drive the odometer to count the number of rotations. Combined with the vehicle's diameter parameters, accurate speed and distance information can be obtained. However, when the vehicle slips, the wheels spin, drift laterally, etc., it is impossible to accurately measure the real-time speed, nor can it provide lateral speed data. In addition, the odometer also faces problems such as wheel wear and tire pressure changes.

[0003] Doppler speed radar can measure the speed of the carrier itself relative to the ground in a non-contact measurement method through the Doppler effect, thereby solving the speed measurement problems in the case of slipping and lateral drift when measuring speed with the odometer, as well as the accumulated errors caused by wheel wear and tire pressure changes.

[0004] Existing vehicle-mounted Doppler speed radar equipment includes: vehicle anti-collision radar, train speed radar. Among them:

[0005] Vehicle-mounted anti-collision radar is used to test the relative position and speed information between the vehicle and the obstacle. It does not require high speed accuracy. Most of them adopt a multi-receive antenna system. The radar uses a linear frequency modulation mode to obtain the speed and distance information of multiple targets. The characteristic of this radar is multi-target monitoring. The focus is on the relative position and distance information between the target and the vehicle rather than the speed information of the vehicle relative to the ground. Therefore, it is impossible to obtain high-precision speed information of the vehicle relative to the ground.

[0006] Train speed radar is used to measure the forward speed of a train traveling on a fixed track. It uses a fixed single-beam antenna to radiate the track to obtain the Doppler frequency, and obtains speed information by matching the track's strong reflection target algorithm. Since this mode uses a single beam, the beam irradiation direction is along the train's running direction, and the lateral speed cannot be calculated. At the same time, the vertical speed caused by the vehicle's bumps will be superimposed on the forward speed, introducing speed measurement errors, resulting in large measurement errors.

[0007] The above two radars have relatively low speed measurement accuracy and are not suitable for installation on vehicles. They cannot meet the requirements for measuring the forward speed and lateral speed of the car relative to the ground. Summary of the invention

[0008] The purpose of the present invention is to address the deficiencies of the above-mentioned prior art and to provide a lateral two-beam vehicle-mounted Doppler speed measurement radar device to achieve radar measurement of the forward velocity and lateral velocity of the ground in a complex environment.

[0009] To achieve the above object, the lateral two-beam vehicle-mounted Doppler speed radar device of the present invention comprises an antenna, a transceiver, a signal processing unit and a power supply assembly, wherein the power supply assembly is respectively connected to the transceiver and the signal processing unit, and is characterized in that:

[0010] The antenna is configured as a receiving antenna and a transmitting antenna, each antenna having two feeding ends, and switching between a forward transmitting beam, a backward transmitting beam, a forward receiving beam, and a backward receiving beam is achieved by applying signals to different feeding ends;

[0011] The transceiver is used to generate a K-band low phase noise continuous wave signal, which is output through two radio frequency output terminals of a transmitting beam selection switch and respectively connected to two feed terminals of a transmitting antenna to generate ground radiation signals with different directions, and generate echo signals with Doppler frequency shift after being reflected by the ground; after receiving the corresponding directional echo signal, the receiving antenna is output from the corresponding two feed terminals of the receiving antenna, enters the transceiver through two radio frequency input terminals of the receiving beam selection switch, and is successively subjected to low noise amplification and zero intermediate frequency orthogonal mixing, and outputs two orthogonal Doppler frequency shift signals to the signal processing unit;

[0012] The signal processing unit is used to perform FFT transformation, matched filtering and solution on two orthogonal Doppler frequency shift signals in sequence to obtain the Doppler frequency shift value, and solve the forward and lateral speed values ​​of the current carrier based on the Doppler frequency shift and the antenna beam pointing angle, and at the same time control the transceiver's transceiver timing and beam switching timing.

[0013] Furthermore, the forward beam and the backward beam of the antenna are symmetrically distributed on both sides of the antenna H-plane, the E-plane antenna beam pointing angle α is 16°~24°, and the lobe width is ≤4°; the forward beam and the backward beam of the antenna are distributed on the same side of the antenna E-plane, the H-plane antenna beam pointing angle β is 10°~12°, and the lobe width is ≤6°.

[0014] Furthermore, the two feeding ends of the transmitting antenna are respectively a forward beam feeding end I 11 And the transmission back beam feed end I 12 , the transmitting forward beam feed end I 11 and the first RF output terminal O of the transceiver 21 Connect the transmitting rear beam feed terminal I 12 and the second RF output terminal O of the transceiver 22 The two feeding ends of the receiving antenna are respectively receiving the forward beam feeding end O 11 and receiving backward beam feed end O 12, the receiving forward beam feed end O 11 and the first RF input terminal I of the transceiver 21 Connect the receiving back beam feed terminal O 12 and the second RF input terminal I of the transceiver 22 connect.

[0015] Furthermore, the transceiver includes: a 100MHz temperature-compensated crystal oscillator, a phase-locked source, a power divider, a transmission beam selection switch, a reception beam selection switch, a low-noise amplifier, an orthogonal mixing circuit, and a power supply processing function circuit; the temperature-compensated crystal oscillator generates a 100MHz reference signal, enters the phase-locked source for frequency multiplication and phase locking, so as to generate a 24.2GHz low phase noise transmission signal and a phase-locked indication voltage, and the phase-locked indication terminal O 25 Output; the transmission signal passes through the power divider and then passes through the transmission beam selection switch from the first RF output terminal O 21 and the second RF output terminal O 22 The radar echo is output through the first RF input terminal I 21 and the second RF input terminal I 22 It enters the transceiver receiving beam selection switch and generates orthogonal I and Q signals through a low noise amplifier and an orthogonal mixer circuit.

[0016] Furthermore, the signal processing unit includes: an A / D sampling circuit, an ARM microcontroller and an RS422 interface circuit. The A / D sampling circuit performs digital sampling on the two input I and Q signals and sends the sampled data to the ARM microcontroller. The ARM microcontroller performs FFT and matched filtering on the data to solve the Doppler frequency shift value, and calculates the current carrier forward velocity V according to the frequency shift and the currently controlled beam state and the corresponding beam angle information. X and lateral velocity V Y The data is sent to the external host computer through the RS422 interface circuit. At the same time, the ARM microcontroller receives instructions from the external host computer to complete radar self-test, beam control and power supply control.

[0017] The signal processing unit has three output terminals, namely, a timing control output terminal O 31 、422 serial port output port O 32 , power control output terminal O 33 , the timing control output O 31 and the transceiver timing control input terminal I 23 Connect the 422 serial port output port O 32 Connected to an external host computer, the power supply controls the output terminal O 33 Connect the second input terminal I to the power supply component 42The signal processing unit has four input terminals, namely, I intermediate frequency input terminal I 31 、Q-way intermediate frequency input terminal I 32 , power input terminal I 33 , phase lock indication input terminal I 34 , the I-way intermediate frequency input terminal I 31 and the intermediate frequency output terminal O of the transceiver I 23 Connect the Q-way IF input terminal I 32 Q-channel intermediate frequency output port O of the transceiver 24 Connect the power input terminal I 33 The second output terminal O of the power supply component 42 Connect the phase lock indication input terminal I 34 Phase-locked with the transceiver output O 25 connect.

[0018] The present invention has the following beneficial effects:

[0019] 1. The antenna of the present invention adopts a symmetrical two-beam configuration, which can not only measure the forward speed and lateral speed of the carrier at the same time, but also eliminate the random error of forward speed measurement caused by vehicle vibration and bumps, and can be freely installed on the side and bottom of the carrier vehicle without beam obstruction.

[0020] 2. The present invention adopts K-band transmission carrier frequency, so under the same beam width, the antenna size is small, which is conducive to the miniaturization requirements of products, the frequency is high, the corresponding wavelength is small, the Doppler frequency shift is large at the same speed, and the speed resolution is high;

[0021] 3. The present invention adopts a dual-antenna continuous wave carrier signal, which can maximize the effective utilization rate of the echo, and the data processing time is long, thereby improving the measurement accuracy of the Doppler frequency and thus improving the speed measurement accuracy;

[0022] 4. The invention adopts a zero intermediate frequency orthogonal mixing scheme in the transceiver, thereby avoiding multi-stage frequency conversion, reducing the cost of the transceiver, and being able to distinguish positive speed from negative speed by orthogonal phase ratio;

[0023] 5. Compared with traditional speed measuring equipment, the present invention has the following advantages:

[0024] Compared with odometer equipment, the present invention can simultaneously measure the forward speed and lateral speed of the carrier without cumulative error;

[0025] Compared with inertial navigation equipment, the average speed information of the present invention is very accurate, the speed measurement error is stable, there is no cumulative effect, no calibration is required, and no warm-up preparation time is required;

[0026] Compared to GPS, the speed measurement of the present invention is completely autonomous and does not require a ground station or satellite transmitter;

[0027] Compared with laser speed measurement, the present invention is an all-weather system that can work in all kinds of meteorological conditions and is not affected by rain, snow and dust environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0029] Figure 2 It is a schematic diagram of the principle of the transceiver in the present invention;

[0030] Figure 3 It is a schematic diagram of beam configuration in the present invention;

[0031] Figure 4 It is a schematic diagram of the principle of the signal processing unit in the present invention;

[0032] Figure 5 It is a schematic diagram of the installation position of the present invention. DETAILED DESCRIPTION

[0033] The present invention is further described below in conjunction with the accompanying drawings.

[0034] Reference Figure 1 The vehicle-mounted Doppler speed radar device of the present invention comprises an antenna 1, a transceiver 2, a signal processing unit 3, and a power supply component 4. Among them:

[0035] Antenna 1 is divided into a transmitting antenna and a receiving antenna. The transmitting antenna has two input terminals, namely, a transmitting forward beam feeding terminal I 11 And the transmission back beam feed end I 12 The K-band continuous wave signal generated by the receiver is respectively transmitted through the forward beam feed end I 11 And the transmission back beam feed end I 12 Different directions of radiation are formed to the ground. When the radar moves relative to the ground, an echo signal with Doppler frequency shift is generated. The receiving antenna has two output terminals, namely the forward beam feed terminal O 11 and receiving backward beam feed end O 12 The receiving antenna receives the echo signal at a specific angle from the ground and feeds the forward beam to the receiving end O 11 and receiving backward beam feed end O 12 Output to transceiver.

[0036] The transceiver 2 has four input terminals and five output terminals, namely, a first RF input terminal I 21 , the second RF input terminal I 22 , timing control input terminal I 23 , power supply input terminal I 24 , the first RF output terminal O 21 , the second RF output terminal O22 、I-way intermediate frequency output terminal O 23 , Q-way intermediate frequency output terminal O 24 And phase lock indication output O 25 The transceiver is used to generate a low phase noise K-band transmission signal, and through the transmission beam selection switch, respectively, by the first RF output terminal O 21 , the second RF output terminal O 22 Output, and then through the RF coaxial cable to the transmitting antenna to transmit the forward beam feed end I 11 And the transmission back beam feed end I 12 Connected to excite the transmitting antenna; the first RF input terminal I 21 and the second RF input terminal I 22 Through coaxial cables, they are connected to the receiving antenna to receive the forward beam feed end O 11 and receiving backward beam feed end O 12 The received echo signals of different directions are processed in time-sharing mode through the beam selection switch, and then low-noise amplification and zero intermediate frequency orthogonal mixing are performed to finally generate two orthogonal Doppler frequency shift signals, which are respectively transmitted from the intermediate frequency output terminal I to the intermediate frequency output terminal O 23 , Q-way intermediate frequency output terminal O 24 The transceiver can also generate a phase-locked indication voltage to determine whether the output frequency of the transmitted signal is normal. This signal is output from the phase-locked indication output terminal O 25 Output.

[0037] The signal processing unit 3 has four input terminals and three output terminals, namely, an intermediate frequency input terminal I 31 、Q-way intermediate frequency input terminal I 32 , power input terminal I 33 , Phase-locked indication input terminal I 34 , timing control output terminal O 31 、422 serial port output port O 32 and power control output O 33 The signal processing unit has an intermediate frequency input terminal I 31 and Q-way intermediate frequency input terminal I 32 I intermediate frequency output terminal O of the transceiver 23 , Q-way intermediate frequency output terminal O 24 The connection is used to perform A / D sampling, frequency resolution and speed resolution on the orthogonal Doppler frequency shift signal output by the transceiver in sequence, and output the speed resolution result through the 422 serial port output port O 32 Output to the host computer; timing control output terminal O 31 Through discrete signal lines and transceiver timing control input terminal I 23 Connection, control the working sequence of the transmitting beam selection switch and the receiving beam selection switch of the transceiver; the phase lock indication input terminal I 34Phase-locked with the transceiver output O 25 Connection, used to monitor the transceiver phase lock indication voltage; the power supply controls the output terminal O 33 Connected to the power supply component, it is used to control the voltage output of the power supply component according to the host computer instructions, and then control the working power of the transceiver.

[0038] The power supply component 4 has two input terminals and two output terminals, namely, I 41 ,I 42 , O 41 , O 42 , the first input terminal I 41 Connected to the host computer, used to convert the vehicle-mounted working power voltage provided by the host computer to the voltage required for the transceiver and signal processing components to work. The second input terminal I 42 The signal processing unit power control output terminal O 33 connected to receive a voltage output control instruction of a signal processing component, and its first output terminal O 41 The transceiver power supply input terminal I 24 connected to provide the power supply voltage required by the transceiver, and its second output terminal O 42 The signal processing unit power input terminal I 33 Connection, used to provide the power supply voltage required by the signal processing unit.

[0039] Reference Figure 2 The transceiver 2 comprises: a 100MHz temperature-compensated crystal oscillator 21, a phase-locked source 22, a power divider 23, a transmission beam selection switch 24, a receiving switch beam selection switch 25, a low-noise amplifier 26, an orthogonal mixing circuit 27, and a power supply processing function circuit 28; the temperature-compensated crystal oscillator generates a 100MHz low phase noise signal, which enters the phase-locked source for frequency multiplication phase locking to generate a 24.2GHz low phase noise transmission signal and a phase-locked indication voltage. When the phase-locked source is locked, that is, outputs a 24.2GHz signal, the phase-locked indication voltage is high. When the phase-locked source has no output or outputs other frequencies, the phase-locked indication voltage is low. The phase-locked indication voltage is output by the phase-locked indication terminal O 25 Output. The transmission signal F with a frequency of 24.2GHz o , after being divided by the power divider, two signals are output, one of which enters the transmit beam selection switch and is transmitted from the first RF output terminal O 21 and the second RF output terminal O 22 Time-sharing output, the working state of the transmit beam selection switch is controlled by the timing control input terminal I 23 The other local oscillator as the orthogonal mixer enters the orthogonal mixer circuit for orthogonal phase shifting to generate two local oscillators of equal amplitude and orthogonality F o 0° and F o 90°. With Doppler shift F DThe echo signal F o +F D Through the first RF input terminal I 21 and the second RF input terminal I 22 Enter the transceiver receive beam selection switch, which is also controlled by the timing control input terminal I 23 The control signal is applied to control the switch to output the echo signal of each channel in time-sharing mode. After being amplified by the low-noise amplifier, it enters the orthogonal mixer circuit. In the orthogonal mixer circuit, the echo is first divided into equal amplitude and phase to generate a frequency F o +F D Two identical signals, and then the signal is respectively compared with the two orthogonal local oscillator signals F o 0° and F o 90° mixing to eliminate the carrier frequency F o , and then low-pass filtering is performed to filter out the high-order mixing components generated by the mixing, and finally the two orthogonal Doppler frequency shift signals F are output. D 0° and F D 90°, respectively from the I intermediate frequency output terminal O 23 and Q-channel intermediate frequency output terminal O 24 Output.

[0040] In order to improve the speed measurement accuracy, the antenna beam pointing angle and configuration relationship are optimized. The forward beam and the backward beam of the antenna are symmetrically distributed on both sides of the antenna H surface. The E-surface antenna beam pointing angle α is 16°~24°, and the lobe width is ≤4°; the forward beam and the backward beam of the antenna are distributed on the same side of the antenna E surface. The H-surface antenna beam pointing angle β is 10°~12°, and the lobe width is ≤6°. Figure 3 shown.

[0041] Reference Figure 4 The signal processing unit includes: an A / D sampling circuit 31, an ARM microcontroller 32 and an RS422 interface circuit 33.

[0042] The A / D sampling circuit 31 performs digital sampling on the two input I and Q signals and sends the sampled data to the ARM microcontroller 32;

[0043] The ARM microcontroller 32 performs FFT and matched filtering on the sampled data to solve the Doppler frequency shift value, and calculates the current carrier forward velocity V according to the frequency shift and the currently controlled beam state and the corresponding beam angle information. X and lateral velocity V Y , the calculation principle and formula are as follows:

[0044] According to the Doppler effect, electromagnetic waves will produce a Doppler frequency shift F between relatively moving objects. D, when far away from the target, the Doppler shift takes a negative value, and when close to the target, it takes a positive value. Therefore, the Doppler shift can be obtained based on the basic formula related to the wavelength of the electromagnetic wave, the relative speed and direction: Where λ represents the wavelength of the carrier, V represents the relative motion speed, and γ represents the angle between the propagation direction of the electromagnetic wave and the direction of the relative motion speed.

[0045] according to Figure 3 From the radar antenna beam pointing and configuration relationship shown in the figure, it can be seen that the forward beam of the antenna intersects with the ground at point A, and the backward beam of the antenna intersects with the ground at point B, and A and B are symmetrically distributed. α is the antenna E-plane beam pointing angle, β is the H-plane antenna beam pointing angle, θ is the beam incidence angle to the ground, and it satisfies: sin 2 θ=sin 2 α+sin 2 β,

[0046] Depend on Figure 4 The geometric relationship and the principle of Doppler effect can be used to obtain the Doppler frequency shift expression:

[0047]

[0048]

[0049] Where Vx is the forward velocity component of the carrier, Vy is the lateral velocity component of the carrier, Vz is the vertical velocity component of the carrier, λ is the wavelength of the carrier, and f A represents the Doppler frequency shift corresponding to the forward beam, f B The Doppler frequency shift of the backward beam is proportional to the three-axis velocity V of the radar. X 、V Y , the projection of Vz in the direction of the beam pointing is inversely proportional to the carrier wavelength λ.

[0050] The radar forward velocity V is calculated by the above formula X and lateral velocity V Y The following formula:

[0051]

[0052]

[0053] From the forward speed V X and lateral velocity V Y It can be seen that the vertical velocity effect on V X However, at V YThe direction will bring about twice the vertical speed error, but in actual use, the vehicle is driving on the road and the vertical speed mean is zero, so it does not affect the speed mean error, but the vehicle vibration and bumps will increase the instantaneous error of lateral speed measurement.

[0054] Calculated radar forward velocity V X and lateral velocity V Y The signals are sent to an external host computer through the RS422 interface circuit 33, and the ARM microcontroller 32 receives the external host computer instructions to complete radar self-test, beam control and power supply control.

[0055] refer to Figure 5 The radar in this example is installed on the side of the carrier vehicle at a height of 1m to 2.5m. The radar is installed parallel to the vehicle and is positioned by screws. The host computer supplies power and issues commands for operation / silence. When working, the radar outputs forward speed and lateral speed information in real time. When silent, the radar has no output and no electromagnetic radiation.

[0056] The above description is only a specific example of the present invention and does not constitute any limitation to the present invention. It is obvious that for professionals in this field, after understanding the content and principles of the present invention, it is possible to make various modifications and changes in form and details without departing from the principles and structures of the present invention. However, these modifications and changes based on the ideas of the present invention are still within the scope of protection of the claims of the present invention.

Claims

1. A lateral two-beam vehicle-mounted Doppler speed measurement radar device, comprising an antenna (1), a transceiver (2), a signal processing unit (3) and a power supply assembly (4), wherein the power supply assembly (4) is connected to the transceiver (2) and the signal processing unit (3) respectively, and is characterized in that: The antenna is set to have two transmitting and receiving antennas, each antenna has two feeding ends, and switching of the forward transmitting beam, the backward transmitting beam, the forward receiving beam, and the backward receiving beam is realized by applying signals to different feeding ends; the forward beam and the backward beam of the antenna are symmetrically distributed on both sides of the antenna H surface, the E-surface antenna beam pointing angle α is 16° to 24°, and the lobe width is ≤4°, which is used to solve the forward speed of the radar and eliminate the speed measurement error caused by vibration and turbulence; the forward beam and the backward beam of the antenna are distributed on the same side of the antenna E surface, the H-surface antenna beam pointing angle β is 10° to 12°, and the lobe width is ≤6°, which is used to solve the lateral speed; The transceiver is used to generate a K-band low phase noise continuous wave signal, which is output through two radio frequency output terminals of a transmitting beam selection switch and respectively connected to two feed terminals of a transmitting antenna to generate ground radiation signals with different directions, and generate echo signals with Doppler frequency shift after being reflected by the ground; after receiving the corresponding directional echo signal, the receiving antenna is output from the corresponding two feed terminals of the receiving antenna, enters the transceiver through two radio frequency input terminals of the receiving beam selection switch, and is successively subjected to low noise amplification and zero intermediate frequency orthogonal mixing, and outputs two orthogonal Doppler frequency shift signals to the signal processing unit; The signal processing unit is used to perform FFT transformation, matched filtering and calculation on two orthogonal Doppler frequency shift signals in sequence to obtain the Doppler frequency shift value, and calculate the forward and lateral speed values ​​of the current carrier based on the Doppler frequency shift value and the antenna beam pointing angle, and at the same time control the transceiver's transceiver timing and beam switching timing.

2. The device according to claim 1, characterized in that: The two feeding ends of the transmitting antenna are respectively the transmitting forward beam feeding end I 11 And the transmission back beam feed end I 12 , the transmitting forward beam feed end I 11 and the first RF output terminal O of the transceiver 21 Connect the transmitting rear beam feed terminal I 12 and the second RF output terminal O of the transceiver 22 connect; The two feeding ends of the receiving antenna are respectively the receiving forward beam feeding end O 11 and receiving backward beam feed end O 12 , the receiving forward beam feed end O 11 and the first RF input terminal I of the transceiver 21 Connect the receiving back beam feed terminal O 12 and the second RF input terminal I of the transceiver 22 connect.

3. The device according to claim 1, characterized in that: The signal processing unit is provided with three output terminals, namely, a timing control output terminal O 31 、422 serial port output port O 32 , power control output terminal O 33 , the timing control output O 31 and the transceiver timing control input terminal I 23 Connect the 422 serial port output port O 32 Connected to an external host computer, the power supply controls the output terminal O 33 Connect the second input terminal I to the power supply component 42 .

4. The device according to claim 1, characterized in that: The signal processing unit has four input terminals, namely, I intermediate frequency input terminal I 31 、Q-way intermediate frequency input terminal I 32 , power input terminal I 33 , phase lock indication input terminal I 34 , the I-way intermediate frequency input terminal I 31 and the intermediate frequency output terminal O of the transceiver I 23 Connection, the Q-way IF input terminal I 32 Q-channel intermediate frequency output port O of the transceiver 24 Connect the power input terminal I 33 The second output terminal O of the power supply component 42 Connect the phase lock indication input terminal I 34 Phase-locked with the transceiver output O 25 connect.

5. The device according to claim 1, characterized in that: The first input terminal I of the power supply component 41 Connected to the external host computer, the first output terminal O of the power supply component 41 The power supply input terminal I 24 connect.

6. The device according to claim 1, characterized in that: The transceiver (2) comprises: a 100 MHz temperature compensated crystal oscillator (21), a phase-locked source (22), a power divider (23), a transmission beam selection switch (24), a reception beam selection switch (25), a low noise amplifier (26), an orthogonal mixing circuit (27), and a power supply processing function circuit (28); the temperature compensated crystal oscillator (21) generates a 100 MHz reference signal, which enters the phase-locked source (22) for frequency multiplication and phase locking to generate a 24.2 GHz low phase noise transmission signal and a phase-locked indication voltage, and the phase-locked indication terminal O 25 The transmission signal is transmitted through the power divider (23) and then through the transmission beam selection switch (24) respectively from the first RF output terminal O 21 and the second RF output terminal O 22 The radar echo is output through the first RF input terminal I 21 and the second RF input terminal I 22 The signals enter the transceiver receiving beam selection switch (25), and are passed through a low noise amplifier (26) and an orthogonal mixer circuit (27) to generate orthogonal I and Q signals.

7. The device according to claim 1, characterized in that: The signal processing unit comprises: an A / D sampling circuit (31), an ARM microcontroller (32) and an RS422 interface circuit (33). The A / D sampling circuit (31) performs digital sampling on the two input I and Q signals and sends the sampled data to the ARM microcontroller (32). The ARM microcontroller (32) performs FFT and matched filtering on the data to calculate the Doppler frequency shift value, and calculates the current carrier forward speed V according to the frequency shift value, the current controlled beam state and the corresponding beam angle information. X and lateral velocity V Y The data is sent to an external host computer via an RS422 interface circuit (33), and the ARM microcontroller (32) receives instructions from the external host computer to complete radar self-checking, beam control and power supply control.

8. The device according to claim 7, characterized in that: The ARM microcontroller (32) calculates the current carrier forward velocity value V according to the Doppler frequency shift value and the antenna beam pointing angle. X and the lateral velocity V Y , through the following formula: Among them, f A is the measured forward beam Doppler frequency shift value, f B is the measured backward beam Doppler frequency shift value, α is the E-plane beam pointing angle of the antenna, β is the H-plane pointing angle of the antenna, θ is the beam incidence angle to the ground, and it satisfies: sin 2 θ=sin 2 α+sin 2 β; Vz represents the vertical velocity component of the carrier, and Vz is zero when the vehicle is traveling on the road.

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