Radar signal detection device and method

Abstract

The present invention provides a radar signal detection device and method, wherein the device includes a signal transceiver component, a laser ranging module, and a controller electrically connected to the signal transceiver component and the laser ranging module: the signal transceiver component is used to, in a detection mode, sweep the radar signal emitted by the radar to be measured according to a sweeping mode corresponding to the frequency band of the radar signal emitted by the radar to be measured, and transmit the swept radar signal to the controller; the laser ranging module is used to transmit a laser beam to the radar to be measured and receive a reflected laser beam from the radar to be measured, determine the distance between the device and the radar to be measured based on the laser beam and the reflected laser beam, and transmit the distance value to the controller; the controller is used to determine the radiation power and frequency band of the radar to be measured based on the radar signal and the distance value, thereby reducing the cost of detecting the radar to be measured and enabling the radiation power and frequency band to be obtained more quickly.

Description

Technical Field

[0001] The present invention relates to the field of radar technology, and in particular to a radar signal detection device and method. Background Art

[0002] At present, millimeter-wave radars in the 76-81GHz frequency band may be installed on the entire vehicle or on the road beam or gantry, depending on the application scenario. As the installed capacity of vehicle-mounted millimeter-wave radars and traffic millimeter-wave radars increases year by year, millimeter-wave radars have many brands, models, and frequency bands, making them difficult to detect. During the use of millimeter-wave radars, it is necessary to regularly check whether they are working properly. The main focus of millimeter-wave radar indicators is whether the radiation power and operating frequency band meet the requirements of the manual and laws and regulations. There are currently three methods for detecting the radiation signal of millimeter-wave radars in the 76-81GHz frequency band:

[0003] (1) The test system consists of a spectrum analyzer, RF coaxial cable and millimeter wave horn antenna;

[0004] (2) A test system consisting of a spectrum analyzer, RF coaxial cable, a spectrum spreader module, and a millimeter-wave horn antenna;

[0005] (3) A test system consisting of a radar target simulator, a radio frequency coaxial cable, a spectrum spread module, and a millimeter wave horn antenna.

[0006] In the above methods, spectrum analyzers, millimeter-wave horn antennas, and spectrum expansion modules are high-precision, high-value instruments and equipment. A large number of cables are required to electrically connect the instruments, which are prone to performance degradation and functional damage. In addition, the procurement and maintenance cycles are long, and the testing costs are high. Summary of the Invention

[0007] The present invention provides a radar signal detection device that reduces the cost of millimeter-wave radar detection and can quickly analyze the frequency band and radiation power of the radar to be tested. The specific scheme is as follows:

[0008] In a first aspect, a radar signal detection device is provided, the device comprising a signal transceiver component, a laser ranging module, and a controller electrically connected to the signal transceiver component and the laser ranging module:

[0009] The signal transceiver component is used to sweep the radar signal emitted by the radar to be tested according to a sweep mode corresponding to a preset frequency band in the detection mode and transmit the swept radar signal to the controller;

[0010] The laser ranging module is used to transmit a laser beam to the radar to be measured and receive a reflected laser beam from the radar to be measured, determine a distance value between the device and the radar to be measured based on the laser beam and the reflected laser beam, and send the distance value to the controller;

[0011] The controller is used to determine the radiation power and frequency band of the radar to be measured according to the radar signal and the distance value.

[0012] Furthermore, the controller is further configured to send the determined radiation power and frequency band to a display module for display.

[0013] Furthermore, the signal transceiver component includes at least one receiving antenna arranged in a preset polarization direction and a transceiver for processing the radar signal;

[0014] The transceiver includes a receiving chain corresponding to each of the receiving antennas;

[0015] The receiving chain includes a mixer for down-converting the radar signal to a preset frequency, a filtering unit connected to the mixer for filtering the frequency-converted radar signal, a gain amplifier connected to the filtering unit for amplifying the filtered radar signal, and an analog-to-digital converter connected to the gain amplifier for converting the amplified radar signal into a digital signal.

[0016] Furthermore, the controller is further configured to determine at least one frequency sweep band and a frequency sweep order of the at least one frequency sweep band according to the frequency band;

[0017] The frequency sweeping modes corresponding to the frequency bands are as follows:

[0018] Each of the receiving antennas performs frequency sweeping in each of the frequency sweeping bands in sequence according to the frequency sweeping sequence, and transmits the radar signal obtained by the frequency sweeping to the corresponding receiving link.

[0019] Furthermore, the filtering unit includes a high-pass filtering unit connected to the mixer and a low-pass filtering unit connected to the gain amplifier;

[0020] The controller determines an intermediate frequency bandwidth according to the cutoff frequencies corresponding to the high-pass filtering unit and the low-pass filtering unit, respectively, and the intermediate frequency bandwidth is within a preset frequency;

[0021] If the radar signal filtered by the filtering unit is within the intermediate frequency bandwidth, the radar signal is transmitted to the analog-to-digital converter, and the analog-to-digital converter converts the radar signal into a digital signal and then sends it to the controller.

[0022] Furthermore, the controller is further configured to determine the radiation power of the radar signal according to the following method;

[0023] determining a free space loss of radiated power of the radar signal based on the distance value;

[0024] Determining a polarization compensation value and a target measured power according to a preset polarization direction of the receiving antenna corresponding to each receiving link and a measured power of the radar signal received by the receiving antenna corresponding to each receiving link;

[0025] The target measured power is compensated according to the polarization compensation value and the free space loss to thereby determine the radiation power of the radar signal.

[0026] Furthermore, the preset polarization direction includes a first polarization direction and a second polarization direction perpendicular to the first polarization direction, and the first polarization direction and the second polarization direction both correspond to at least one receiving antenna;

[0027] Wherein, if the measured power of the radar signals received by all the receiving antennas is the same, the polarization compensation value is a preset constant value;

[0028] If the difference between the measured powers of the radar signals received by the receiving antenna corresponding to the first polarization direction and the second polarization direction is greater than a preset threshold, the polarization compensation value is 0, and the measured power with the larger value is used as the target measured power.

[0029] Furthermore, the signal transceiver component further includes at least one transmitting antenna;

[0030] In the calibration mode, the controller controls the at least one transmitting antenna to transmit a frequency modulated continuous wave signal to the target object, and the at least one receiving antenna is further configured to receive an echo signal generated by the target object after receiving the frequency modulated continuous wave signal, and transmit the echo signal to the controller after being processed by the transceiver;

[0031] The laser ranging module is further configured to emit a laser beam toward the target object so that the target object feeds back a reflected laser beam, determine a first distance between the device and the target object based on the laser beam and the reflected laser beam, and send the first distance to the controller;

[0032] The controller is also used to determine the first power of the echo signal based on the first distance, determine the second distance between the device and the target object based on the echo signal received by the receiving antenna and determine the second power of the echo signal based on the second distance, and compare the first power with the second power to complete the power calibration process.

[0033] Furthermore, the free space loss is calculated according to the following formula:

[0034] FSPL = 20logS + 20logF + 32.45;

[0035] Wherein, FSPL is the free space loss, S is the distance value, and F is the radiation frequency of the radar to be measured.

[0036] Furthermore, the laser ranging module includes a laser emitting unit and a laser emitting lens for emitting a laser beam, and a laser receiving unit and a laser receiving lens for receiving a reflected laser beam.

[0037] Furthermore, the controller is further configured to determine whether the device has entered the far field area of the radar to be tested based on the distance value;

[0038] Wherein, if the device does not enter the far field area, controlling the laser ranging module to continue ranging before entering the far field area;

[0039] If the device has entered the far-field area, the laser ranging module is controlled to measure the distance again and the radiation power and frequency band of the radar to be measured are determined according to the obtained distance value and the received radar signal.

[0040] Furthermore, it also includes:

[0041] Built-in power module for providing power;

[0042] a power management module, electrically connected to the built-in power module, for managing the power supply process of the signal transceiver component, the laser ranging module, the controller, and the display module;

[0043] The multifunctional key input module is used to enable the user to input control instructions for the device.

[0044] In a second aspect, a radar signal detection method is provided, the method comprising:

[0045] Sweeping the radar signal emitted by the radar to be tested according to a sweeping mode corresponding to a preset frequency band;

[0046] emitting a laser beam toward the radar to be measured and receiving a reflected laser beam from the radar to be measured, and determining a distance value between the device and the radar to be measured based on the laser beam and the reflected laser beam;

[0047] The radiation power and frequency band of the radar to be measured are determined according to the scanned radar signal and the distance value.

[0048] Through the technical solution of the present invention, on the one hand, the radar signal detection device does not need to use high-precision, high-value instruments and equipment such as spectrum analyzers, millimeter-wave horn antennas and spread spectrum modules, thereby avoiding the problems of long procurement and maintenance cycles and high requirements for users. On the other hand, the radar signal detection device of the present invention is an independent device, which is provided with a controller for controlling the signal transceiver component and the laser ranging module and processing the data transmitted from the signal transceiver component and the laser ranging module. It does not need to be connected to external test software. Therefore, the operation is simple and the radiation power and frequency band of the radar to be tested can be analyzed quickly. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0050] Figure 1 Schematic diagram of the structure of a radar signal detection device in an embodiment of the present invention;

[0051] Figure 2 is a structural diagram of a transceiver in an embodiment of the present invention;

[0052] Figure 3 This is a process for processing a radar radiation signal to be measured in a fixed frequency band in an embodiment of the present invention;

[0053] Figure 4 The following is a detection process of a radar to be tested in a detection mode according to an embodiment of the present invention;

[0054] Figure 5 The power calibration process in the calibration mode according to an embodiment of the present invention is as follows;

[0055] Figure 6 The figure is a flow chart of a radar signal detection method according to an embodiment of the present invention. DETAILED DESCRIPTION

[0056] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making any creative efforts shall fall within the scope of protection of the present invention.

[0057] The present invention provides a radar signal detection device, which includes a signal transceiver component, a laser ranging module, and a controller electrically connected to the signal transceiver component and the laser ranging module:

[0058] The signal transceiver component is used to sweep the radar signal emitted by the radar to be tested according to the sweep mode corresponding to the preset frequency band in the detection mode and transmit the swept radar signal to the controller;

[0059] The laser ranging module is used to transmit a laser beam to the radar to be measured and receive the reflected laser beam from the radar to be measured, determine the distance value between the device and the radar to be measured based on the laser beam and the reflected laser beam, and send the distance value to the controller;

[0060] The controller is used to determine the radiation power and frequency band of the radar to be tested according to the radar signal and the distance value.

[0061] In the present invention, a radar signal detection device uses a signal transceiver component to sweep the radar signal emitted by the radar under test according to a preset sweep mode. A laser ranging module is used to measure the distance between the device and the radar under test. A controller is used to determine the radiation power and frequency band of the radar under test based on the radar signal and the distance value, thereby detecting the radiation power of the radar under test. On the one hand, the device does not require high-precision and high-value instruments and equipment such as spectrum analyzers, millimeter-wave horn antennas, and spread spectrum modules, thereby avoiding the problems of long procurement and maintenance cycles and high user requirements. On the other hand, the radar signal detection device of the present invention is an independent device. The device is provided with a controller for controlling the signal transceiver component and the laser ranging module and processing the data transmitted from the signal transceiver component and the laser ranging module. It does not need to be connected to external test software. Therefore, it is simple to operate and can quickly analyze the radiation power and frequency band of the radar under test. On the other hand, the device of the present invention is portable and suitable for detecting millimeter-wave radars outdoors or in the field. Furthermore, the radar signal detection device of the present invention can detect single-band and multi-band 76-81 GHz frequency band automotive millimeter-wave radar and traffic millimeter-wave radar radiation signals under far-field conditions.

[0062] The radar signal detection device of the present invention will be described in detail below with reference to specific embodiments and accompanying drawings.

[0063] like Figure 1 As shown, a radar signal detection device includes a signal transceiver component 10, a laser ranging module 20, and a controller 30 electrically connected to the signal transceiver component 10 and the laser ranging module 20:

[0064] The signal transceiver component 10 is used to sweep the radar signal emitted by the radar to be tested according to the sweep mode corresponding to the preset frequency band in the detection mode and transmit the swept radar signal to the controller 30;

[0065] The laser ranging module 20 is used to transmit a laser beam to the radar to be measured and receive the reflected laser beam from the radar to be measured, determine the distance between the device and the radar to be measured based on the laser beam and the reflected laser beam, and send the distance value to the controller 30;

[0066] The controller 30 is used to determine the radiation power and frequency band of the radar to be measured according to the radar signal and the distance value.

[0067] Furthermore, the signal transceiver component 10 has multiple modes. In the detection mode, the signal transceiver component 10 is only used to receive radar signals emitted by the radar to be tested, and does not emit radio frequency signals itself, thereby avoiding interference with the radar signals emitted by the radar to be tested.

[0068] Before detecting the radar to be tested, different frequency scanning modes are used for different preset frequency bands. For example, the radiation signals of automotive millimeter-wave radars and traffic millimeter-wave radars are usually in the 76-81GHz frequency band. Therefore, the corresponding frequency scanning mode can be pre-set according to the 76-81GHz frequency band, so that the signal transceiver component can receive the radar signal with the preset frequency band more comprehensively and accurately.

[0069] During airborne propagation, the radar signal of the radar under test typically experiences a certain amount of free-space loss. This free-space loss is related to the distance between the radar signal detection device and the radar under test. Therefore, the controller 30 accurately determines the free-space loss of the radar signal of the radar under test based on the distance value and, further, accurately determines the radiated power and frequency band of the radar under test by combining the radar signal transmitted by the signal transceiver assembly 10. During operation, the laser ranging module 20 emits a very fine laser beam toward the radar under test. The optoelectronic element within the laser ranging module 20 receives the laser beam reflected from the surface of the radar under test. A timer measures the time from laser beam emission to laser beam reception, calculating the distance from the present invention to the radar under test. Distance is generally calculated using the formula S = c * t / 2, where c represents the speed of light in air, approximately 299,550,000 m / s, and t represents the time required for the laser beam to travel back and forth between the radar signal detection device of the present invention and the radar under test, expressed in seconds.

[0070] Furthermore, the controller 30 is further configured to send the determined radiation power and frequency band to the display module 40 for display.

[0071] In order to facilitate the acquisition of the radiation power and frequency band of the radar to be tested, the radar signal detection device in the present invention also includes a display module 40. After determining the radiation power and frequency band, the controller 30 sends the radiation power and frequency band to the display module 40 for display.

[0072] Furthermore, the signal transceiver component 10 includes at least one receiving antenna 101 arranged in a preset polarization direction and a transceiver 102 for processing the radar signal;

[0073] The transceiver 102 includes a receiving chain 1021 corresponding to each receiving antenna 101;

[0074] The receiving chain 1021 includes a mixer 10211 for down-converting the radar signal to a preset frequency, a filtering unit 10212 connected to the mixer 10211 for filtering the frequency-converted radar signal, a gain amplifier 10213 connected to the filtering unit 10212 for amplifying the filtered radar signal, and an analog-to-digital converter 10214 connected to the gain amplifier 10213 for converting the amplified radar signal into a digital signal.

[0075] Further references Figure 1 The signal transceiver assembly 10 includes four receiving antennas 101, each receiving antenna 101 is connected to a transceiver 102. Figure 2 , which is a schematic structural diagram of the transceiver 102 . For each receiving antenna 101 , the transceiver 102 has a corresponding input interface, and the input interface corresponds to a corresponding interface link 1021 .

[0076] For example, Figure 2 As shown, the transceiver 102 includes a frequency modulation signal generating circuit 1022, which includes a driver 10221, a first switch 10222 connected to the driver 10221, a first phase-locked loop 10223 connected to the first switch 10222, and a second switch 10224 connected to the first phase-locked loop 10223. The driver 10221 is connected to a crystal oscillator, and the crystal oscillator triggers the driver 2011 to generate a 40 MHz clock signal.

[0077] In order to ensure that the clock signal in the transceiver 102 and the clock signal in the laser ranging module 20 and the controller 30 are synchronized, in the main transceiver, the clock signal generated by the driver 2011 is transmitted to the first switch 10222. The clock signal transmission mode of the first switch 10222 includes a cascade input type and a cascade output type. The clock signal is transmitted to the outside of the main transceiver through the cascade output type, and then divided into at least three paths. These three paths are respectively transmitted to the clock interface of the transceiver 102, and the other two paths are respectively transmitted to the clock interfaces in the laser ranging module 20 and the controller 30.

[0078] Among them, the clock signal transmitted to the clock interface of the transceiver 102 is input to the first switch 10222, and then transmitted by the first switch 10222 to the first phase-locked loop 10223. The first phase-locked loop 10223 converts the clock signal into a local oscillator signal with 26 GHz, and then divides it into at least two paths, one of which is input to the second switch 10224 through the input port of the local oscillator signal of the main transceiver, and the other is transmitted to the receiving link 1021. In the detection mode, the transmitting link 1023 does not transmit the radio frequency signal. Therefore, the mode of the second switch 10224 is the sleep mode.

[0079] The receiving chain 1021 includes a mixer 10211 for down-converting the radar signal to a preset frequency, a filtering unit 10212 connected to the mixer 10211 for filtering the frequency-converted radar signal, a gain amplifier 10213 connected to the filtering unit 10212 for amplifying the filtered radar signal, and an analog-to-digital converter 10214 connected to the gain amplifier 10213 for converting the amplified radar signal into a digital signal. Furthermore, the second switch 10224 transmits the 26 GHz local oscillator signal to the frequency multiplier of the receiving chain 1021, multiplies the frequency of the local oscillator signal, and transmits it to the mixer. Under the action of the local oscillator signal, the radar signal is down-converted to a 20 MHz frequency conversion signal, and then filtered in the filtering unit 10212, amplified by the gain amplifier 10213, converted into a digital signal by the analog-to-digital converter 10214, and transmitted to the controller 30. The controller 30 processes the received digital signal to obtain the measured power of the radar signal of the radar to be tested.

[0080] In one embodiment, the controller 30 is further configured to determine at least one frequency sweep band and a frequency sweep order of at least one frequency sweep band according to the frequency band;

[0081] The frequency sweeping modes corresponding to the frequency bands are as follows:

[0082] Each receiving antenna scans each scanning band in sequence and transmits the scanned radar signal to the corresponding receiving link.

[0083] In the present invention, different frequency bands of radar signals correspond to different sweep frequency bands and the scanning order of the sweep frequency bands is different. For example, in order to detect the millimeter-wave radar signal in the 76-81 GHz frequency band, eight triangle wave sweep frequency bands are set and the sweep order is: 76-77 GHz, 76.6-77.2 GHz, 77.2-77.8 GHz, 77.8-78.4 GHz, 78.4-79 GHz, 79-79.6 GHz, 79.6-80.2 GHz, and 80.2-81 GHz.

[0084] In the frequency sweeping mode, each receiving antenna 101 sweeps each frequency sweeping band in sequence and transmits the swept radar signal to the corresponding receiving link 1021 .

[0085] In one embodiment, the filtering unit 10212 includes a high-pass filtering unit connected to the mixer and a low-pass filtering unit connected to the gain amplifier;

[0086] The controller determines the intermediate frequency bandwidth according to the cutoff frequencies corresponding to the high-pass filter unit and the low-pass filter unit, and the intermediate frequency bandwidth is within the preset frequency;

[0087] If the radar signal filtered by the filtering unit is within the intermediate frequency bandwidth, the radar signal is transmitted to the analog-to-digital converter, and the analog-to-digital converter converts the radar signal into a digital signal and then sends it to the controller.

[0088] For example, if the radar radiation frequency to be measured is between 76 and 81 GHz, the eight sub-bands mentioned above are sequentially scanned and down-converted with the local oscillator signal of the transceiver. The preset frequency of down-conversion is less than 20 MHz. Since the available intermediate frequency bandwidth of the transceiver is not greater than 20 MHz, the frequency response of the high-pass filter unit and the low-pass filter unit is used to obtain an approximate band-pass filter frequency response. The base noise power is inversely proportional to the bandwidth. In order to reduce the base noise and improve the signal-to-noise ratio, the cutoff frequency of the high-pass filter can be set to 3.1 MHz and the cutoff frequency of the low-pass filter can be set to 12.5 MHz. Thus, the intermediate frequency bandwidth is 3.1-12.5 MHz. Figure 3 As shown in the figure, as long as the down-converted frequency of the radar signal under test falls within the intermediate frequency bandwidth, the frequency band of the radar signal under test is within the sweep frequency band. If the radar under test operates in multiple frequency bands, as long as the frequency band does not exceed 76-81 GHz, the frequency band of the radar signal under test will always fall within one or more of the eight swept frequency bands mentioned above, thereby improving the accuracy of the radiated power calculation of the radar under test.

[0089] In one embodiment, the controller 30 is further configured to determine the radiated power of the radar signal according to the following method;

[0090] Determine the free space loss of the radiated power of the radar signal based on the distance value;

[0091] Determining a polarization compensation value and a target measured power according to a preset polarization direction of a receiving antenna corresponding to each receiving link and a measured power of a radar signal received by the receiving antenna corresponding to each receiving link;

[0092] The target measured power is compensated according to the polarization compensation value and the free space loss to determine the radiated power of the radar signal.

[0093] In the present invention, when the radar detection device enters the far field of the radar to be tested, the frequency band and radiation power of the radar signal of the radar to be tested can be measured. The far field refers to the area in which the angular distribution of the radiation field is independent of the distance, generally using the formula 2*D 2 / λ to calculate the far-field range, where D is the radar's antenna array length (in meters) and λ represents the carrier wavelength of the radar's transmitted signal (in meters). To reduce weight and material costs, millimeter-wave radars are typically designed with dimensions close to the antenna array length. Therefore, the radar's maximum overall dimension can be considered D in the formula.

[0094] Furthermore, in order to more easily evaluate the far field, the radar signal detection device in the present invention can generally be considered to have entered the far field where the frequency band and radiation power of the radar signal of the radar to be tested can be measured when the distance between the device and the traffic millimeter-wave radar is more than 50 meters and the distance between the device and the automobile millimeter-wave radar is more than 5 meters.

[0095] The radar signal detection device of the present invention is in the far field of the radar to be measured. The built-in laser ranging module 20 starts to measure the precise distance value from the radar signal detection device to the radar to be measured. The free space loss of the radiation signal of the radar to be measured can be calculated according to the formula FSPL (dB) = 20logS + 20logF + 32.45, where S represents the distance value between the radar to be measured and the radar signal detection device, in meters, and F represents the radiation frequency of the radar to be measured, in GHz.

[0096] Furthermore, in addition to the impact of free space loss on the magnitude of the radiated power, the angle between the polarization direction of the receiving antenna and the polarization direction of the radar to be measured also affects the magnitude of the radiated power. Therefore, the present invention determines a polarization compensation value and a target measured power based on the preset polarization direction of the receiving antenna corresponding to each receiving link and the measured power of the radar signal received by the receiving antenna corresponding to each receiving link. The target measured power is then compensated for based on the polarization compensation value and free space loss to determine the radiated power of the radar signal.

[0097] Specifically, the preset polarization direction includes a first polarization direction and a second polarization direction perpendicular to the first polarization direction, and the first polarization direction and the second polarization direction each correspond to at least one receiving antenna;

[0098] If the measured power of the radar signals received by all receiving antennas is the same, the polarization compensation value is a preset constant value;

[0099] If the difference between the measured powers of the radar signals received by the receiving antennas corresponding to the first polarization direction and the second polarization direction is greater than a preset threshold, the polarization compensation value is set to 0, and the measured power with the larger value is used as the target measured power.

[0100] Exemplarily, the first polarization direction is +45° and the second polarization direction is -45°. If the transmitting antenna of the radar to be measured is horizontally polarized or vertically polarized, then there will be polarization loss between the radar signal and the receiving antenna with +45° polarization and the receiving antenna with -45° polarization. The polarization compensation value is a constant value, which can be 3dB for example. At this time, the measured power of the radar signal received by each receiving antenna is the same, and the target measured power is the measured power.

[0101] If the transmitting antenna of the radar under test is polarized at +45°, the radar signal received by the receiving antenna with +45° polarization has a much higher power than the signal received by the receiving antenna with -45° polarization. Therefore, the difference between the measured powers is greater than the preset threshold. In this case, the target measured power is the measured power corresponding to the receiving antenna with +45° polarization, and the polarization compensation value is 0.

[0102] If the transmitting antenna of the radar under test is polarized at -45°, the radar signal received by the -45° polarized receiving antenna has a much higher power than the signal received by the +45° polarized receiving antenna. Therefore, the difference between the two measured powers is greater than the preset threshold. In this case, the target measured power is the measured power corresponding to the -45° polarized receiving antenna, and the polarization compensation value is 0.

[0103] Furthermore, the signal transceiver component 10 further includes at least one transmitting antenna 103;

[0104] In the calibration mode, the controller 30 controls at least one transmitting antenna 103 to transmit a frequency modulated continuous wave signal to the target object, and at least one receiving antenna 103 is further configured to receive an echo signal generated by the target object after receiving the frequency modulated continuous wave signal, and transmit the echo signal to the controller 30 after processing by the transceiver 102;

[0105] The laser ranging module 20 is further configured to emit a laser beam toward a target object so that the target object feeds back a reflected laser beam, determine a first distance between the device and the target object based on the laser beam and the reflected laser beam, and send the first distance to the controller 30;

[0106] The controller 30 is also used to determine the first power of the echo signal based on the first distance, determine the second distance between the device and the target object based on the echo signal received by the receiving antenna and determine the second power of the echo signal based on the second distance, and compare the first power with the second power to complete the power calibration process.

[0107] like Figure 1 As shown, the signal transceiver component 10 includes at least one transmitting antenna 103. Figure 2 As shown, the transceiver 102 further includes a transmission chain 1023 connected to a second switch 10224 .

[0108] The transmission chain 1023 also includes a frequency multiplier, a phase shifter, and a third switch. In the calibration mode, the second switch 10224 is in the normal mode. The 26 GHz frequency-modulated local oscillator signal is transmitted by the second switch 10224 to the frequency multipliers of all transmission chains, multiplying the 26 GHz frequency-modulated continuous wave signal to a preset frequency band, which can be 76-81 GHz. The working bandwidth can be adjusted arbitrarily between the maximum bandwidth of 4 GHz and the minimum bandwidth of 0 GHz according to the needs of the system. The phase shifter, switch, and radio frequency unit then perform phase modulation and amplitude control to form a radio frequency signal, reaching transmission channel 1, transmission channel 2, and transmission channel 3, and is transmitted by the three transmitting antennas 103 corresponding to transmission channel 1, transmission channel 2, and transmission channel 3, and radiates to the outside world through the antenna cover. The frequency bands of the frequency modulated continuous wave signals transmitted by the transmitting link 1023 have a certain order. For example, for the millimeter wave radar signal in the 76-81 GHz frequency band, in order to enable the receiving link 1021 to receive the corresponding echo signal in the above-mentioned frequency sweep order, the transmitting channel transmits the frequency modulated continuous wave signal in the order of 76-77 GHz, 76.6-77.2 GHz, 77.2-77.8 GHz, 77.8-78.4 GHz, 78.4-79 GHz, 79-79.6 GHz, 79.6-80.2 GHz, and 80.2-81 GHz.

[0109] The target object in the present invention can be a corner reflector. In far-field conditions, the laser ranging module 20 in the present invention measures the relative distance between the corner reflector and the target object. The laser ranging module 20 emits a laser beam toward the target object, causing the radar under test to reflect the laser beam back. The distance between the device and the target object is determined based on the laser beam and the reflected laser beam, and the distance is sent to the controller 30. Furthermore, the free space loss of the radar radiation signal under test can be calculated according to the formula FSPL (dB) = 20logS + 20logF + 32.45, where S represents the distance between the target object and the radar signal detection device in meters, and F represents the frequency of the radio frequency signal emitted by the transmission link 1023 in GHz. After determining the free space loss, the first power of the echo signal can be determined based on the free space loss.

[0110] Furthermore, after the echo signal received by the receiving antenna 101 is transmitted to the controller 30, the controller can calculate the second distance between the target object and the radar signal detection device and measure the second power of the echo signal based on the second distance. That is, the present invention obtains the first power and the second power through free space loss and millimeter wave ranging, respectively, and compares the first power with the second power. If the difference between the two is within a preset range, the power calibration process is completed. To facilitate the user to know the calibration process and calibration results, the display module 40 will display the calibration process and calibration results.

[0111] Furthermore, the laser ranging module 20 includes a laser emitting unit 201 and a laser emitting lens 202 for emitting a laser beam, and a laser receiving unit 203 and a laser receiving lens 204 for receiving a reflected laser beam.

[0112] After being emitted by the laser emitting unit 201, the laser beam passes through the laser emitting lens and irradiates the radar to be measured or the surface of the target object. The laser beam is reflected by the radar to be measured or the surface of the target object. The reflected laser beam passes through the laser receiving lens 204 and is transmitted to the laser receiving unit 203.

[0113] The laser ranging module 20 also includes a laser transceiver controller 205 for controlling the transmission and reception of lasers and the transmission of distance data. The laser transceiver controller 205 also includes a transceiver control interface connected to the laser emitting unit 201 and the laser receiving unit 203, a clock interface connected to the transceiver 102 for receiving the clock signal transmitted by the transceiver 102, a ranging module control interface and a distance data interface connected to the controller 30, which respectively realize the reception of the laser ranging control signal of the controller 30 and the distance data measured by interacting with the controller 30.

[0114] Furthermore, the controller 30 is further configured to determine whether the device has entered the far field area of the radar to be tested based on the distance value;

[0115] If the device does not enter the far field area, the laser ranging module is controlled to continue ranging before entering the far field area;

[0116] If the device has entered the far field area, the laser ranging module is controlled to measure the distance again and the radiation power and frequency band of the radar to be measured are determined based on the obtained distance value and the received radar signal.

[0117] The controller 30 determines whether the radar has entered the far field area of the radar to be tested, thereby ensuring the accuracy of the radiation power detection during the radar signal detection process of the radar to be tested.

[0118] Furthermore, the radar signal detection device further includes:

[0119] A built-in power supply module 50 is used to provide power;

[0120] The power management module 60 is electrically connected to the built-in power module 50 and is used to manage the power supply process of the signal transceiver component 10, the laser ranging module 20, the controller 30 and the display module 40;

[0121] The multi-function key input module 70 is used to enable the user to input control instructions for the device.

[0122] In the radar signal detection device of the present invention, a built-in power supply module 50 is provided. Therefore, the device does not require an external power supply and can be used for detecting radars to be tested in the field. In addition, the power management module 60 is used to power other modules, and the multi-function key input module 70 is used to facilitate receiving user control instructions, thereby reducing the requirements on the user.

[0123] Furthermore, if Figure 4 FIG. 1 shows the detection process of a radar under test in the detection mode of the present invention. After the user turns on the device and selects the radar model to be tested, detection of the radar begins. After the radar signal detection device begins the first ranging measurement, it determines whether it has entered the far field of the radar under test. If not, it prompts the user that it has not entered the far field and requires the user to move the radar signal detection device. During this process, the radar signal detection device continues to measure distance and prompts the user after entering the far field. The user then fixes the position of the radar signal detection device and measures the distance again. The current distance value is saved and free space loss is calculated based on the distance value. A polarization compensation value is determined based on the polarization direction of the transmitting antenna of the radar signal under test and the polarization direction of the receiving antenna of the radar signal detection device. Furthermore, the frequency band of the radar signal is measured based on the detected radar signal. If the detected radar signal is within the applicable range, the current frequency band value is saved and the measured power is further determined. The radiated power is determined based on the free space loss, the polarization compensation value, and the measured power. The radar signal detection device displays the radiated power, distance value, and frequency band of the radar under test. During this process, if the frequency band is not within the applicable range, the frequency band will be displayed, but the subsequent radiation power measurement process will not be performed;

[0124] like Figure 5As shown, the calibration process of the present invention in the calibration mode is first fixed in the far field area. After the user turns on the device, he selects the frequency band to be calibrated and starts ranging the corner reflector. On the one hand, the free space loss is determined based on the distance value measured by the laser ranging, and the first measurement power of the echo signal is calculated. On the other hand, millimeter wave ranging can be performed using the frequency modulated continuous wave signal transmitted by the transmitting antenna and the frequency modulated continuous wave signal received by the receiving antenna. The second measurement power is determined and saved based on this distance value. The first measurement power is compared with the second measurement power to determine whether the difference between the two is within a preset range. If so, the calibration power is completed and the calibration process and results are displayed. If not, the corresponding calibration process and results are also displayed.

[0125] The radar signal detection device of the present invention has the following beneficial effects:

[0126] (1) According to different frequency sweep modes, it can detect single-band and multi-band 76-81GHz automotive millimeter-wave radar and traffic millimeter-wave radar radiation signals under far-field conditions;

[0127] (2) It can detect signals with multiple polarization modes, such as vertical polarization, horizontal polarization, +45° polarization, and -45° polarization of millimeter-wave radar antennas, and use algorithms to compensate for polarization loss, thereby improving the accuracy of radiated power calculation;

[0128] (3) The built-in laser ranging module can measure the distance between the radar under test and the detection device of this solution, calculate the attenuation of electromagnetic wave free space transmission, and correct the received signal power of each receiving channel, so as to more accurately evaluate the radiation power of the radar under test;

[0129] (4) The device of the present invention is a portable device, powered by a built-in battery or an external interface, and can be handheld or mounted on a test vehicle. The radar signal information of the radar to be tested is read on the display interface of the device, or the radiation signal information of the radar to be tested is stored and displayed on an external host computer;

[0130] (5) The device of the present invention has different modes. Generally, when it works in detection mode, it will not radiate frequency modulated continuous wave signals to the outside world, thereby not affecting the normal operation of the radar under test. In calibration mode, it uses the corner reflector as the target object to check the working status of each internal module and the calibration of the receiving power in a self-transmitting and self-receiving manner.

[0131] like Figure 6 As shown, a radar signal detection method provided by the present invention includes:

[0132] S601, sweeping the radar signal of the radar to be tested according to a preset sweeping mode corresponding to the frequency band;

[0133] S602, transmitting a laser beam to the radar to be measured and receiving a reflected laser beam from the radar to be measured, and determining a distance value between the device and the radar to be measured based on the laser beam and the reflected laser beam;

[0134] S603: Determine the radiation power and frequency band of the radar to be measured according to the scanned radar signal and the distance value.

[0135] Furthermore, the radiation power and frequency band are displayed.

[0136] Further, the radar signal received by at least one receiving antenna arranged according to a preset polarization direction is transmitted to a receiving link corresponding to each receiving antenna;

[0137] In the receiving chain, the radar signal is down-converted to a preset frequency, the radar signal with the preset frequency is filtered, the radar signal is amplified after filtering, and then the amplified radar signal is converted into a digital signal.

[0138] Further, determining at least one sweep frequency band and a sweep order of at least one sweep frequency band according to the frequency band of the radar signal;

[0139] Each receiving antenna scans each scanning band in sequence and transmits the scanned radar signal to the corresponding receiving link.

[0140] Furthermore, the intermediate frequency bandwidth is determined according to the cutoff frequencies corresponding to the high-pass filter unit and the low-pass filter unit, and the intermediate frequency bandwidth is within a preset frequency;

[0141] If the radar signal filtered by the filtering unit is within the intermediate frequency bandwidth, the radar signal is converted into a digital signal.

[0142] Further, determining a free space loss of the radiated power of the radar signal based on the distance value;

[0143] Determining a polarization compensation value and a target measured power according to a preset polarization direction of a receiving antenna corresponding to each receiving link and a measured power of a radar signal received by the receiving antenna corresponding to each receiving link;

[0144] The target measured power is compensated according to the polarization compensation value and the free space loss to determine the radiated power of the radar signal.

[0145] Furthermore, the preset polarization direction includes a first polarization direction and a second polarization direction perpendicular to the first polarization direction, and the first polarization direction and the second polarization direction each correspond to at least one receiving antenna;

[0146] If the measured power of the radar signals received by all receiving antennas is the same, the polarization compensation value is a preset constant value;

[0147] If the difference between the measured powers of the radar signals received by the receiving antennas corresponding to the first polarization direction and the second polarization direction is greater than a preset threshold, the polarization compensation value is set to 0, and the measured power with the larger value is used as the target measured power.

[0148] Furthermore, in the calibration mode, at least one transmitting antenna is controlled to transmit a frequency modulated continuous wave signal to the target object, and at least one receiving antenna is further used to receive an echo signal generated by the target object after receiving the frequency modulated continuous wave signal;

[0149] emitting a laser beam to the radar to be tested so that the radar to be tested feeds back a reflected laser beam, determining a first distance between the device and the target object based on the laser beam and the reflected laser beam, and sending the first distance to a controller;

[0150] The first power of the echo signal is determined according to the first distance, the second distance between the device and the target object is determined according to the echo signal received by the receiving antenna and the second power of the echo signal is determined according to the second distance, and the first power is compared with the second power to complete the power calibration process.

[0151] Furthermore, the free space loss is calculated according to the following formula:

[0152] FSPL(dB)=20logS+20logF+32.45;

[0153] Among them, FSPL is the free space loss, S is the distance value, and F is the radiation frequency of the radar to be measured.

[0154] Further, judging whether the device has entered the far field area of the radar to be measured based on the distance value;

[0155] If the far field area is not entered, the ranging is controlled to continue before entering the far field area;

[0156] If the radar has entered the far field area, the distance is measured again and the radiation power and frequency band of the radar to be measured are determined based on the obtained distance value and the received radar signal.

[0157] In summary, although the present invention has been disclosed above with reference to preferred embodiments, the above preferred embodiments are not intended to limit the present invention. A person skilled in the art may make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be based on the scope defined in the claims.

Claims

1. A radar signal detection device, characterized in that: The device includes a signal transceiver component, a laser ranging module, and a controller electrically connected to the signal transceiver component and the laser ranging module: The signal transceiver component is used to sweep the radar signal emitted by the radar to be tested according to the sweep mode corresponding to the preset frequency band in the detection mode and transmit the swept radar signal to the controller; The laser ranging module is used to transmit a laser beam to the radar to be measured and receive a reflected laser beam from the radar to be measured, determine a distance value between the device and the radar to be measured based on the laser beam and the reflected laser beam, and send the distance value to the controller; The controller is used to determine the radiation frequency band of the radar to be tested based on the radar signal scanned; and determining a free space loss of the radiated power of the radar signal based on the distance value; determining a polarization compensation value and a target measured power based on a preset polarization direction of a receiving antenna corresponding to each receiving link and the measured power of the radar signal received by the receiving antenna corresponding to each receiving link; The target measured power is compensated according to the polarization compensation value and the free space loss to thereby determine the radiation power of the radar signal.

2. The device according to claim 1, wherein The controller is further configured to send the determined radiation power and the frequency band to a display module for display.

3. The device according to claim 1, wherein The signal transceiver assembly includes at least one receiving antenna arranged in a preset polarization direction and a transceiver for processing the radar signal; The transceiver includes a receiving chain corresponding to each of the receiving antennas; The receiving chain includes a mixer for down-converting the radar signal to a preset frequency, a filtering unit connected to the mixer for filtering the frequency-converted radar signal, a gain amplifier connected to the filtering unit for amplifying the filtered radar signal, and an analog-to-digital converter connected to the gain amplifier for converting the amplified radar signal into a digital signal.

4. The device according to claim 3, wherein: The controller is further configured to determine at least one frequency sweep band and a frequency sweep order of the at least one frequency sweep band according to the frequency band; The frequency sweeping modes corresponding to the frequency bands are as follows: Each of the receiving antennas performs frequency sweeping in each of the frequency sweeping bands in sequence according to the frequency sweeping sequence, and transmits the radar signal obtained by the frequency sweeping to the corresponding receiving link.

5. The device according to claim 3, wherein The filtering unit includes a high-pass filtering unit connected to the mixer and a low-pass filtering unit connected to the gain amplifier; The controller determines an intermediate frequency bandwidth according to the cutoff frequencies corresponding to the high-pass filtering unit and the low-pass filtering unit, respectively, and the intermediate frequency bandwidth is within a preset frequency; If the radar signal filtered by the filtering unit is within the intermediate frequency bandwidth, the radar signal is transmitted to the analog-to-digital converter, and the analog-to-digital converter converts the radar signal into a digital signal and then sends it to the controller.

6. The device according to claim 1, wherein The preset polarization direction includes a first polarization direction and a second polarization direction perpendicular to the first polarization direction, and the first polarization direction and the second polarization direction both correspond to at least one receiving antenna; Wherein, if the measured power of the radar signals received by all the receiving antennas is the same, the polarization compensation value is a preset constant value; If the difference between the measured powers of the radar signals received by the receiving antenna corresponding to the first polarization direction and the second polarization direction is greater than a preset threshold, the polarization compensation value is 0, and the measured power with the larger value is used as the target measured power.

7. The device according to claim 3, wherein The signal transceiver component further includes at least one transmitting antenna; In the calibration mode, the controller controls the at least one transmitting antenna to transmit a frequency modulated continuous wave signal to the target object, and the at least one receiving antenna is further configured to receive an echo signal generated by the target object after receiving the frequency modulated continuous wave signal, and transmit the echo signal to the controller after being processed by the transceiver; The laser ranging module is further configured to emit a laser beam toward the target object so that the target object feeds back a reflected laser beam, determine a first distance between the device and the target object based on the laser beam and the reflected laser beam, and send the first distance to the controller; The controller is also used to determine the first power of the echo signal based on the first distance, determine the second distance between the device and the target object based on the echo signal received by the receiving antenna and determine the second power of the echo signal based on the second distance, and compare the first power with the second power to complete the power calibration process.

8. The device according to claim 1, wherein The free space loss is calculated according to the following formula: FSPL=20logS+20logF+32.45; Wherein, FSPL is the free space loss, S is the distance value, and F is the radiation frequency of the radar to be measured.

9. The device according to claim 1, wherein The laser ranging module includes a laser emitting unit and a laser emitting lens for emitting a laser beam, and a laser receiving unit and a laser receiving lens for receiving a reflected laser beam.

10. The device according to any one of claims 1 to 9, characterized in that The controller is further configured to determine whether the device has entered the far field area of the radar to be tested based on the distance value; Wherein, if the device does not enter the far field area, controlling the laser ranging module to continue ranging before entering the far field area; If the device has entered the far-field area, the laser ranging module is controlled to measure the distance again and the radiation power and frequency band of the radar to be measured are determined according to the obtained distance value and the received radar signal.

11. The device according to claim 2, wherein Also includes: Built-in power module for providing power; a power management module, electrically connected to the built-in power module, for managing the power supply process of the signal transceiver component, the laser ranging module, the controller, and the display module; The multifunctional key input module is used to enable the user to input control instructions for the device.

12. A radar signal detection method, characterized in that: The method comprises: Sweep the radar signal emitted by the radar to be tested according to the sweep mode corresponding to the preset frequency band; emitting a laser beam to the radar to be measured and receiving a reflected laser beam from the radar to be measured, and determining a distance value between the radar signal detection device according to any one of claims 1 to 11 and the radar to be measured based on the laser beam and the reflected laser beam; The radiation frequency band of the radar to be tested is determined based on the radar signal scanned; determining a free space loss of radiated power of the radar signal based on the distance value; Determining a polarization compensation value and a target measured power according to a preset polarization direction of a receiving antenna corresponding to each receiving link and a measured power of a radar signal received by the receiving antenna corresponding to each receiving link; The target measured power is compensated according to the polarization compensation value and the free space loss to thereby determine the radiation power of the radar signal.

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