Outfield imaging measurement device

Abstract

The utility model discloses external field imaging measurement equipment, which comprises an array antenna, a radio frequency transceiving system, an A / D system, a processing system and a power supply system, the array antenna comprises a transmitting linear array and a receiving linear array; the radio frequency transceiving system is used for providing signal excitation for the transmitting linear array and receiving radio signals of the receiving linear array; the A / D system comprises an AD sampling module and a DA conversion module; the processing system comprises a main control computer and a storage board, and the main control computer, the storage board and the A / D system are electrically connected through a communication bus; and the processing system performs imaging processing according to the sampling signal and controls the working states of the array antenna and the radio frequency transceiver system. According to the invention, the target is electrically scanned through the array antenna beam, so that the traditional mechanical scanning is effectively replaced, and the test efficiency is greatly improved; a one-dimensional ultra-wideband phased array arrangement mode is adopted, and single-station receiving and transmitting and high-resolution two-dimensional imaging are achieved; the equipment is highly integrated, the target test result can be displayed in real time, and the field single-person test operation portability and environmental practicability are improved.

Description

Technical Field

[0001] This application relates to a radar target scattering characteristic detection device, and particularly to a miniaturized portable outdoor imaging measurement device. Background Art

[0002] In the field of radar target scattering characteristic detection, outdoor imaging measurement devices are used for high-resolution imaging and characteristic analysis of target objects. These devices are widely applied in fields such as military, meteorology, and environmental monitoring. However, existing outdoor imaging measurement devices have many technical bottlenecks and limitations in practical applications, mainly reflected in aspects such as high mechanical complexity, poor portability, cumbersome operation and debugging, low integration level, and weak signal processing ability.

[0003] First of all, existing devices generally use mechanical scanning methods for target imaging, achieving field of view scanning by moving antennas or reflectors; this method increases the mechanical complexity and maintenance cost of the devices, and at the same time restricts the scanning speed and imaging accuracy, making it difficult to meet the requirements of efficient and accurate measurements. For example, the invention patent with the publication number CN104614726B proposes an array retractable portable MIMO-SAR measurement radar system, which needs to complete the support of the MIMO antenna array through an antenna rack, and also serves as the radar high-frequency combination and the antenna array retraction control unit to realize the lifting operation of the MIMO antenna array. In addition, this system also has the following problems:

[0004] The device is large in volume and heavy in weight, with poor portability, and is not convenient to carry and deploy in complex environments such as the wild. Due to the bulkiness and complexity of the device, multiple people are required to cooperate to complete the installation, which affects the work efficiency. In practical applications, the device needs to be frequently moved and assembled, which puts higher requirements on the portability of the device.

[0005] Each functional module is relatively independent, lacking a highly integrated design, resulting in the overall device being bulky and complex to operate. The connection and debugging between modules require a large amount of time and manpower, reducing the use convenience and fast response ability of the device.

[0006] In terms of signal sampling and processing, traditional devices have high requirements for sampling rate and processing rate. According to the Nyquist sampling theorem, high-frequency signals need to be sampled at a sampling rate more than twice their frequency, which puts higher requirements on the A / D sampling module and subsequent control systems, increasing the complexity of system design.

[0007] There are also deficiencies in the real-time display of test results and operation convenience. Operators need to perform complex settings and debugging, and cannot quickly obtain test results, which affects work efficiency and the timeliness of testing.

[0008] In summary, existing outdoor imaging measurement devices have many deficiencies in terms of portability, imaging speed and accuracy, integrated design, signal processing efficiency, and operation convenience. There is an urgent need for an improved technical solution to solve these problems and improve the performance and user experience of the device in practical applications. Summary of the Invention

[0009] In view of the problems existing in the prior art, this application provides a miniaturized portable outdoor imaging measurement device. The device has the ability to be quickly assembled and used by a single person, can complete the test without the cooperation of others, and can achieve rapid setup, rapid imaging, and measurement in an outdoor environment.

[0010] An outdoor imaging measurement device, comprising:

[0011] An array antenna, including a transmitting linear array and a receiving linear array;

[0012] A radio frequency transceiver system, electrically connected to the transmitting linear array and the receiving linear array respectively; the radio frequency transceiver system generates a source signal, provides signal excitation for the transmitting linear array, and receives the radio signals of the receiving linear array;

[0013] An A / D system, including an AD sampling module and a DA conversion module, the AD sampling module and the DA conversion module are electrically connected to the radio frequency transceiver system respectively; the radio frequency transceiver system down-converts the radio signal into an intermediate frequency signal, provides it to the A / D system through the AD sampling module for sampling and storage; the A / D system generates an intermediate frequency signal through the DA conversion module and transmits it to the radio frequency transceiver system, and the radio frequency transceiver system up-converts the intermediate frequency signal generated by the DA conversion module and then feeds it into the transmitting linear array;

[0014] A processing system, including a main control computer and a storage board, the main control computer, the storage board, and the A / D system are electrically connected by a communication bus; the processing system performs imaging processing based on the sampling signals of the A / D system, and at the same time sends control signals to the radio frequency transceiver system and the array antenna through the A / D system.

[0015] A power supply system, used to supply power to the array antenna, the radio frequency transceiver system, and the A / D system.

[0016] In one implementation, the radio frequency transceiver system includes a coupler, a first power amplifier, a second power amplifier, an up-conversion component, a frequency synthesis component, and a down-conversion component; the output of the up-conversion component is fed into the transmitting linear array after being processed by the first power amplifier and the coupler in sequence, and the output of the receiving linear array is input into the down-conversion component after being processed by the second power amplifier; the DA conversion module is electrically connected to the up-conversion component, and the AD sampling module is electrically connected to the down-conversion component.

[0017] In one embodiment, the up-conversion component includes a first-stage up-conversion module, a second-stage up-conversion module, and a third-stage up-conversion module connected in series in sequence; the third-stage up-conversion module receives a 220 MHz intermediate-frequency signal from the A / D system, and the 220 MHz intermediate-frequency signal is subjected to three times of up-conversion, filtering, and amplification processing by the third-stage up-conversion module, the second-stage up-conversion module, and the first-stage up-conversion module in sequence to output a radio-frequency signal to the first power amplifier, and after being processed by the first power amplifier and the coupler, it is fed into the transmitting linear array.

[0018] In one embodiment, the down-conversion component includes a first-stage down-conversion module, a second-stage down-conversion module, and a third-stage down-conversion module connected in series in sequence; the first-stage down-conversion module receives a radio-frequency signal from the array antenna, and the radio-frequency signal is down-converted from a high frequency to an intermediate-frequency signal by the first-stage down-conversion module, and the second-stage down-conversion module and the third-stage down-conversion module down-convert the intermediate-frequency signal to a 220 MHz intermediate-frequency signal required by the A / D system.

[0019] Optionally, the second power amplifier is a low-noise amplifier.

[0020] In one embodiment, the device further includes a human-machine interface, and the human-machine interface includes a display unit and a host computer, and the display unit and the host computer are respectively electrically connected to the main control computer of the processing system.

[0021] Further, the power supply system includes a main switch and sub-switches, the main switch is connected to an external input power supply, and the sub-switches are connected to the array antenna, the radio-frequency transceiver system, the A / D system, and the human-machine interface; the main switch divides the external input power supply into multiple paths of power, and the multiple paths of power are supplied to each subsystem through the sub-switches.

[0022] In one embodiment, the power supply system further includes a plurality of filtering modules, and the external input power supply is divided into multiple paths by the main switch and then filtered by the plurality of filtering modules respectively to supply power to each subsystem.

[0023] In one embodiment, the transmitting linear array and the receiving linear array are one-dimensional arrays. Preferably, the number of sub-array units of the transmitting linear array and the receiving linear array is ≥8.

[0024] Compared with the prior art, the present application has the following beneficial effects:

[0025] 1. The system equipment of the present application is highly integrated and can be accommodated in a general-purpose packing box, which is convenient for a single person to carry and test, enhancing the portability of the equipment in the field environment.

[0026] 2. This application scans the target by means of beam electrical scanning of the array antenna, adopts the arrangement mode of one-dimensional ultra-wideband phased array, realizes the integration of transceiver, effectively replaces the traditional mechanical scanning, has a relatively fast speed compared with the traditional mechanical displacement, and has a high sampling rate at the same time, greatly improving the test efficiency.

[0027] 3. This application provides a simple and clear human-machine interface, which conforms to the usage habits of operators; the target test results can be displayed in real time, improving the portability and environmental adaptability of single-operator field tests.

[0028] 4. This application adopts multi-stage up-conversion combined with multi-channel filtering and amplification processing, which can significantly improve the AD sampling rate, making the subsequent signal processing more efficient and accurate, solving the high requirements for signal sampling rate and processing rate, and being beneficial to system design;

[0029] 5. The processing system of this application integrates a high-performance main control computer, which can control each module of the subsystem and devices such as power amplifiers, attenuators, and filters, so as to realize the real-time control of the working mode, working frequency, and acquisition pulse width of the device; it can receive the status information of key components in real time and send the results to the display; combined with high-precision imaging algorithms, such as Chirp Scaling (CS), high-resolution one-dimensional or two-dimensional imaging can be realized. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of the composition of the portable field imaging measurement device according to an embodiment of this application;

[0031] Figure 2 It is the sub-array pattern of the array antenna according to an embodiment of this application;

[0032] Figure 3 It is a schematic diagram of the up-conversion module according to an embodiment of this application;

[0033] Figure 4 It is a schematic diagram of the down-conversion module according to an embodiment of this application;

[0034] Figure 5 It is an imaging diagram of a tank model according to an embodiment of this application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0035] For the convenience of understanding, the relevant technical terms involved in the embodiments of this application will be explained and described below.

[0036] Array antenna: It is a system composed of multiple antennas, which are arranged in a specific way in a plane or three-dimensional space. Compared with traditional single radar antennas, array antennas have higher gain, narrower beam width, and better anti-interference performance. By arranging multiple antennas together in a specific geometric shape, array antennas utilize the mutual interference of signals to enhance the performance of receiving or transmitting signals. The working principle of array antennas is based on two key concepts: phase control and beamforming.

[0037] Phase control: Each antenna in the array antenna can control the transmission or reception time of the signal by adjusting the phase in its circuit. By precisely controlling the phase of each antenna, signals can be superimposed in a specific direction, thereby enhancing the intensity of the target signal. This phase control can achieve beamforming, enabling the antenna system to focus in a specific direction.

[0038] Beamforming: Utilizing phase control, array antennas can achieve beamforming, that is, concentrating energy in a specific direction. By adjusting the phase and amplitude of each antenna, the directivity and width of the beam can be controlled. This enables array antennas to increase the receiving or transmitting sensitivity of signals in a specific direction while reducing interference in other directions.

[0039] Through the above-mentioned phase control, the imaging measurement device based on the array antenna can control the directivity of the beam, thus replacing the mechanical displacement method adopted by traditional radar antennas.

[0040] Refer to Figures 1 - 5 , the portable field imaging measurement device provided in this application includes an array antenna 1, a radio frequency transceiver system 2, an A / D system 3, a processing system 4, and a power supply system 6. The entire set of equipment can be stored in a packing box. The following describes the equipment structure in detail in combination with the specification drawings and preferred embodiments.

[0041] The array antenna 1 is the signal transceiver unit of the entire system equipment, mainly implemented in an array manner, including a transmitting linear array and a receiving linear array, two transceiver sub-arrays, for radio frequency signal transceiver.

[0042] Preferably, the transceiver sub-array adopts a one-dimensional array, and the number of sub-array units ≥ 8. The azimuth resolution depends on the azimuth beam width. The azimuth resolution is equal to the product of the azimuth beam width and the distance to the target. Therefore, when the distance is certain, the narrower the beam width, the smaller the azimuth resolution unit and the higher the azimuth resolution. Figure 2 Shown is the sub-array pattern of an array antenna, where (a) is the first main section (0°) of the pattern, and (b) is the second main section (90°) of the pattern. The basic indicators are: azimuth beam width: 5°, elevation beam width: 30°, gain: ≥ 20 dBi.

[0043] The RF transceiver system 2 is mainly responsible for signal amplification (transmission amplification, reception amplification), frequency up-conversion and down-conversion, and source signal generation, including power amplifiers (power amplifier, low-noise amplifier), up-conversion and down-conversion components, and frequency synthesis components. The frequency synthesis components include a high-stability crystal oscillator and a local oscillator. The up-conversion component is responsible for up-converting the signal and then feeding it into the transmitting antenna array. The output of the receiving antenna array is processed by a low-noise amplifier and then down-converted to an intermediate frequency by the down-conversion component and provided to the A / D system 3 for sampling and real-time storage. In this embodiment, the basic specifications of the up-conversion component are: input triple-intermediate frequency: 220 MHz, output RF signal frequency: 6 - 18 GHz, spurious harmonic suppression: ≤ -50 dBc, triple-intermediate frequency filter bandwidth: ≥ 120 MHz; the main electrical specifications of the down-conversion component are: input RF signal frequency: 6 - 18 GHz, output intermediate frequency signal frequency: 220 MHz, spurious of the output triple-intermediate frequency signal: ≤ -60 dBc, triple-intermediate frequency filter bandwidth: ≥ 120 MHz.

[0044] As Figure 3 shown, the up-conversion component specifically includes a first-stage up-conversion module, a second-stage up-conversion module, and a third-stage up-conversion module. The third-stage up-conversion module receives the 220-MHz intermediate frequency signal from the A / D system 3. The 220-MHz intermediate frequency signal is sequentially subjected to three times of up-conversion, filtering, and amplification processes to output a low-power RF signal to the power amplifier, and after being processed by the power amplifier and the coupler, it is fed into the transmitting antenna array.

[0045] As Figure 4 shown, the down-conversion component specifically includes a first-stage down-conversion module, a second-stage down-conversion module, and a third-stage down-conversion module. The first-stage down-conversion module receives the RF signal from the array antenna 1. The RF signal is processed by the first-stage down-conversion module and down-converted from high frequency to intermediate frequency (first intermediate frequency). The second-stage down-conversion module and the third-stage down-conversion module down-convert the first intermediate frequency signal to the 220-MHz intermediate frequency signal required by the A / D system 3.

[0046] The A / D system 3 includes an AD sampling module and a DA conversion module. It mainly receives the intermediate frequency signal from the down-conversion component through the AD channel, performs AD sampling and real-time storage at a certain duty cycle, number of channels: ≥ 8; and generates an intermediate frequency signal through the DA channel and outputs it to the up-conversion component, number of channels: ≥ 8. In this embodiment, the basic technical specifications of the AD module are: number of analog channels: 8 channels, sampling frequency: up to 200 Msps, input impedance: 50 ohms; the basic technical specifications of the DA module: number of analog channels: 8, conversion frequency: up to 500 Msps, input impedance: 50 ohms.

[0047] The processing system 4 includes a main control computer and a storage board. The main control computer, the storage board, and the A / D system 3 are electrically connected via a communication bus. The processing system 4 performs imaging processing based on the sampling signals of the A / D system 3, and at the same time controls signals to the radio frequency transceiver system 2 and the array antenna 1 through the A / D system 3 to adjust the device working mode, working frequency, acquisition pulse width, and control of devices such as filters. The imaging algorithm can adopt conventional synthetic aperture radar imaging algorithms, such as the Chirp Scaling (CS) algorithm. Figure 5 This is an imaging diagram of a tank model obtained according to the CS imaging algorithm, where (a) represents a two-dimensional imaging diagram placed longitudinally, and (b) represents a two-dimensional imaging diagram placed transversely.

[0048] The power supply system 6 provides power supply and secondary power conversion for the entire system. The power supply system includes a main switch and sub-switches. The main switch receives the external input power, then divides it into four and filters each one to supply power to each subsystem separately, and an additional path can be set separately for backup. Its working process is as follows: After the power is input, it first passes through the system main fuse, then is connected to the main switch. The main switch controls the on / off of the power. After passing through the main switch, the total power is divided into four. Each path is connected to the corresponding output aviation connector on the rear panel after being controlled by the front panel sub-switch. It should be noted that each branch output aviation connector has a fuse.

[0049] Furthermore, this device also includes a human-machine interface 5, which provides a human-machine interaction interface during the operation of the target scattering test system, and realizes control functions including status display, parameter setting, mode selection, data acquisition and storage, etc. Specifically, the human-machine interface 5 includes a display unit and a host computer, and the display unit and the host computer are electrically connected to the main control computer of the processing system 4 respectively. The human-machine interface 5 can also adopt the implementation method of a rugged computer, with a Win7 operating system inside, which can provide strong protection and high environmental adaptability.

[0050] Further preferably, the material of the device structural parts is selected as aerospace aluminum alloy. Through reasonable structural layout and strength analysis of the fixation of the structural parts, the weight of each structural part is reduced, and the overall weight of the device is reduced. The total weight of the device: ≤18 kg, which is convenient for single-person carrying and quick operation in the field.

[0051] It should be noted that the device of the present application involves signal acquisition, processing and control during implementation, including signal amplification processing, frequency up / down conversion processing, imaging processing, control of devices such as working mode / working frequency / acquisition pulse width and attenuator / filter, control of turning on / off the power supply, and display of device status information; the above contents are all mature prior arts, and their specific implementation methods are published in various documents before the filing date of the present application. Therefore, what the present application claims protection for is the device composition independent of the above signal acquisition, processing and control. Although the implementation of the present application requires the application of the above signal acquisition, processing and control, the implementation of the present application does not depend on any unknown computer software program or method and belongs to the protection object of the utility model.

Claims

1. An outfield imaging measurement device, characterized in that: include: An array antenna (1) comprises a transmitting linear array and a receiving linear array; A radio frequency transceiver system (2) is electrically connected to the transmitting linear array and the receiving linear array respectively; The radio frequency transceiver system (2) generates a source signal to provide signal excitation for the transmitting linear array and receives radio signals from the receiving linear array; The A / D system (3) comprises an AD sampling module and a DA conversion module, wherein the AD sampling module and the DA conversion module are electrically connected to the radio frequency transceiver system (2) respectively; the radio frequency transceiver system (2) down-converts the radio signal into an intermediate frequency signal, and provides the signal to the A / D system (3) for sampling and storage through the AD sampling module; the A / D system (3) generates an intermediate frequency signal through the DA conversion module and transmits the signal to the radio frequency transceiver system (2); the radio frequency transceiver system (2) up-converts the intermediate frequency signal generated by the DA conversion module and feeds the signal into the transmitting linear array; The processing system (4) comprises a main control computer and a storage board, wherein the main control computer, the storage board and the A / D system (3) are electrically connected by a communication bus; the processing system (4) performs imaging processing according to the sampling signal of the A / D system (3), and simultaneously sends a control signal to the radio frequency transceiver system (2) and the array antenna (1) through the A / D system (3); A power supply system (6) is used to supply power to the array antenna (1), the radio frequency transceiver system (2), and the A / D system (3).

2. The outfield imaging measurement device according to claim 1, characterized in that: The radio frequency transceiver system (2) comprises a coupler, a first power amplifier, a second power amplifier, an up-conversion component, a frequency synthesis component and a down-conversion component; The output of the up-conversion component is processed by the first power amplifier and the coupler in turn and then fed into the transmitting linear array, and the output of the receiving linear array is processed by the second power amplifier and then input into the down-conversion component; The DA conversion module is electrically connected to the up-conversion component, and the AD sampling module is electrically connected to the down-conversion component.

3. The outfield imaging measurement device according to claim 2, characterized in that: The up-conversion component comprises a primary up-conversion module, a secondary up-conversion module and a tertiary up-conversion module connected in series in sequence; The three-stage up-conversion module receives a 220 MHz intermediate frequency signal from an A / D system (3). The 220 MHz intermediate frequency signal is up-converted and filtered three times and amplified in sequence by the three-stage up-conversion module, the two-stage up-conversion module and the one-stage up-conversion module, and then outputs a radio frequency signal to the first power amplifier. After being processed by the first power amplifier and the coupler, the signal is fed into the transmitting array.

4. The outfield imaging measurement device according to claim 2, characterized in that: The down-conversion component comprises a first-stage down-conversion module, a second-stage down-conversion module and a third-stage down-conversion module connected in series in sequence; The first-stage down-conversion module receives a radio frequency signal from the array antenna (1); the radio frequency signal is processed by the first-stage down-conversion module and then down-converted from a high frequency to an intermediate frequency signal; the second-stage down-conversion module and the third-stage down-conversion module down-convert the intermediate frequency signal to a 220 MHz intermediate frequency signal required by the A / D system (3).

5. The outfield imaging measurement device according to claim 2, characterized in that: The second power amplifier is a low noise amplifier.

6. The outfield imaging measurement device according to claim 1, characterized in that: It also includes a human-machine interface (5), which includes a display unit and a host computer. The display unit and the host computer are electrically connected to the main control computer of the processing system (4) respectively.

7. The outfield imaging measurement device according to claim 6, characterized in that: The power supply system (6) comprises a main switch and sub-switches, the main switch being connected to an external input power supply, and the sub-switches being connected to an array antenna (1), a radio frequency transceiver system (2), an A / D system (3), and a human-machine interface (5); the main switch divides the external input power supply into multiple power supplies, and the multiple power supplies supply power to each subsystem via the sub-switches.

8. The outfield imaging measurement device according to claim 7, characterized in that: The power supply system (6) further comprises a plurality of filter modules. The external input power is divided into multiple paths by a main switch and then filtered by the plurality of filter modules respectively to supply power to each subsystem respectively.

9. The outfield imaging measurement device according to claim 1, characterized in that: The transmitting linear array and the receiving linear array are one-dimensional arrays.

10. The outfield imaging measurement device according to claim 9, characterized in that: The number of sub-array units of the transmitting linear array and the receiving linear array is ≥8.

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