Channel correction architecture, radar and security inspection device

Abstract

The present application relates to the technical field of communications. Provided are a channel correction architecture, a radar and a security inspection device, which aim to solve the problem of inconsistency between channels. The channel correction architecture provided in the present application comprises a feed network and a plurality of transceiver assemblies, wherein a plurality of transceiver channels of the feed network are connected to the plurality of transceiver assemblies in a manner of corresponding to each other on a one-to-one basis; in the channel correction architecture, a signal generator is used for generating a calibration radio-frequency signal, a preamplifier is used for converting the calibration radio-frequency signal, which is generated by the signal generator, into an amplified signal, and a calibrator is used for generating a first correction coefficient on the basis of the calibration radio-frequency signal and the amplified signal; the calibrator is further used for transmitting the calibration radio-frequency signal to the feed network; and the calibration radio-frequency signal is transmitted via the feed network to each transceiver assembly, each transceiver assembly is used for generating a first echo signal on the basis of the calibration radio-frequency signal, and the calibrator is used for generating, on the basis of the calibration radio-frequency signal and each first echo signal, a second correction coefficient corresponding to each transceiver channel, thereby facilitating the effective correction of channels.

Description

A channel correction architecture, radar, and security inspection equipment

[0001] Cross-references to related applications

[0002] This application claims priority to Chinese Patent Application No. 202411463610.5, filed on October 18, 2024, with the title “A Channel Correction Architecture, Radar and Security Inspection Equipment”, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This application relates to the field of communication technology, and in particular to a channel correction architecture, radar, and security inspection equipment. Background Technology

[0004] With the continuous development of communication technology, radar performance has been significantly improved. For example, in large-array millimeter-wave radar, the signal transmission and reception capabilities can be effectively enhanced by employing a larger number of radiating elements. The radiating elements, specifically the radiating oscillators, can transmit and receive electromagnetic waves. In radar, the feed network includes multiple transceiver channels, each connected to a different radiating element. This allows the radio frequency (RF) signal within each channel to be radiated outwards through the corresponding radiating element. Furthermore, the echo signal received by the radiating element can also be transmitted back to the feed network through the transceiver channel. In practical applications, each transceiver channel is equipped with devices such as phase shifters and power amplifiers. When the RF signal and echo signal are transmitted within the channel, inconsistencies in these devices can cause phase shifts and other distortions in both signals, thus affecting the radar's signal transmission and reception performance.

[0005] Furthermore, in practical applications, the phase of the signal propagating in each channel can be adjusted using devices such as phase shifters to achieve functions such as beam scanning. However, inconsistencies between the transmitting and receiving channels can affect beam scanning accuracy. Therefore, how to effectively correct the transmitting and receiving channels has become an urgent technical problem to be solved. Summary of the Invention

[0006] This application provides a channel correction architecture, radar, and security inspection equipment capable of effectively detecting and correcting transceiver channels.

[0007] Firstly, this application provides a channel correction architecture, including a feed network and multiple transceiver components. The feed network has multiple transceiver channels, each corresponding to one of the transceiver components. The channel correction architecture also includes a signal generator, a scaler, and a preamplifier. The signal generator generates a calibration RF signal. The scaler is connected to the signal generator and receives the calibration RF signal generated by the signal generator. The preamplifier is connected between the signal generator and the scaler and converts the calibration RF signal generated by the signal generator into an amplified signal. The scaler determines the distortion of the signal after passing through the preamplifier based on the calibration RF signal and the amplified signal, and generates a first correction coefficient.

[0008] The scaler is also connected to the feed network, and is used to transmit the calibration RF signal to the feed network. The calibration RF signal is transmitted from the feed network to each transceiver component, and each transceiver component generates a first echo signal based on the calibration RF signal. The feed network is also used to transmit the first echo signal generated by each transceiver component to the scaler. The scaler is used to generate a second correction coefficient corresponding to each transceiver channel based on the calibration RF signal and each first echo signal.

[0009] As an example, the calibration signal can be a radio frequency (RF) signal with known parameters such as phase and amplitude. When the calibration RF signal is amplified by a preamplifier, it may be distorted. For example, the phase of the calibration RF signal may be deflected. In the channel correction architecture provided in this application, the calibrator can receive both the calibration RF signal and the amplified signal. By comparing the phase of the calibration RF signal with that of the amplified signal, the distortion between the two signals can be determined.

[0010] In addition, the scaler is also used to transmit the calibration RF signal to the feed network. The feed network has multiple channels, and the signal transmitted in each channel is transmitted to the corresponding transceiver component through multiple transceiver channels for signal transmission and reception.

[0011] When the calibration RF signal is transmitted through each channel in the feed network, the calibration RF signal may be distorted, resulting in inconsistent parameters of the calibration RF signal transmitted from each transceiver channel to the corresponding transceiver component. Additionally, the calibration signal is transmitted and received in each transceiver component, generating a first echo signal. The first echo signal is transmitted to the feed network through the corresponding transceiver channel. The calibrator can compare the received first echo signal with the calibration RF signal to determine the distortion between the two signals.

[0012] In summary, the first correction factor characterizes the phase distortion of the calibration RF signal propagating in the preamplifier. The second correction factor characterizes the phase distortion of the signal propagating between the feed network and the transceiver components. The first correction factor allows for phase correction of the amplified signal, ensuring its phase matches that of the calibration RF signal. The second correction factor facilitates correction for each channel, ensuring that each first echo signal received by the calibrator is in phase with the calibration RF signal, ultimately achieving internal channel correction.

[0013] In one example, the channel calibration architecture also includes a temperature sensor. The temperature sensor detects the ambient temperature and generates a temperature detection signal. A calibrator generates a first calibration coefficient based on the temperature detection signal, the calibration RF signal, and the amplified signal. The calibrator also generates a second calibration coefficient corresponding to each transceiver channel based on the temperature detection signal, the calibration RF signal, and each first echo signal. The first and second calibration coefficients generated by the calibrator are matched to the current ambient temperature. Therefore, in practical applications, the corresponding first and second calibration coefficients can be applied according to different ambient temperatures to achieve temperature compensation, avoiding errors caused by temperature differences and thus achieving better channel calibration.

[0014] In one example, the channel calibration architecture also includes a processor connected to a scaler and a feed network. The processor generates a primary calibration signal based on a first calibration coefficient and a second calibration coefficient. The feed network adjusts the amplitude and phase of the calibration RF signal based on the primary calibration signal, ensuring that the phase and amplitude of each first echo signal received by the scaler are identical. In other words, the scaler can detect inconsistencies between channels, and the combination of the processor and the feed network enables channel consistency.

[0015] In one example, the channel correction architecture also includes multiple radiating components, a receiver, and correction circuitry. The radiating components are connected one-to-one with multiple transceiver components, and are used to radiate electromagnetic waves toward a target and receive a second echo signal reflected from the target. A preamplifier is also connected to the receiver and a feed network, through which the second echo signal is transmitted to the receiver. The correction circuitry is connected to the receiver and is used to generate a third correction coefficient based on the calibration RF signal and the second echo signal of each transceiver channel to facilitate external channel correction.

[0016] In one example, the processor generates a secondary correction signal based on a third correction factor, and the feed network adjusts the amplitude and phase of the second echo signal based on the secondary correction signal so that the phase and amplitude of each second echo signal received by the receiver are the same, thereby achieving effective correction outside the channel.

[0017] In one example, the receiver is connected to a circulator in the preamplifier to receive the amplified signal generated by the preamplifier.

[0018] In one example, the scaler is connected to the preamplifier via a coupler. Alternatively, the coupler can be integrated into the preamplifier itself; the location of the coupler can be adjusted according to specific requirements.

[0019] Secondly, this application also provides a radar with the aforementioned channel correction architecture. In practical applications, the correction function can be run during the radar's power-on phase. Alternatively, the correction function can be implemented at a flexible selected time. By equipping the radar with the aforementioned channel correction architecture, the consistency between channels in the radar can be effectively guaranteed, thereby ensuring the radar's operating performance and beam scanning functions.

[0020] Thirdly, this application also provides a security inspection device, which may include the aforementioned radar. Of course, in practical applications, the security inspection device may also include imaging devices such as a display. By employing the aforementioned radar, fast and efficient security inspections can be achieved, exhibiting good inspection efficiency and accuracy. Attached Figure Description

[0021] Figure 1 is a structural block diagram of a radar provided in an embodiment of this application;

[0022] Figure 2 is a structural block diagram of a channel correction architecture provided in an embodiment of this application;

[0023] Figure 3 is a structural block diagram of another channel correction architecture provided in an embodiment of this application;

[0024] Figure 4 is a structural block diagram of another channel correction architecture provided in an embodiment of this application;

[0025] Figure 5 is a structural block diagram of another channel correction architecture provided in an embodiment of this application;

[0026] Figure 6 is a schematic diagram of a waveform transmission and reception link provided in an embodiment of this application;

[0027] Figure 7 is a schematic diagram of another waveform transmission and reception link provided in an embodiment of this application;

[0028] Figure 8 is a schematic diagram of waveform processing provided in an embodiment of this application. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of this application clearer, the application will now be described in further detail with reference to the accompanying drawings.

[0030] To facilitate understanding of the channel correction architecture provided in this application embodiment, its application scenarios will be introduced first below.

[0031] The channel correction architecture provided in this application can be applied in communication equipment such as radar to detect and adjust parameters such as the phase and amplitude of signals transmitted in the channel, so as to ensure the working performance of the radar.

[0032] For example, as shown in Figure 1, in the example provided in this application, the radar may include a signal generator, a preamplifier, a feed network, a transceiver component, and a radiating component connected in sequence. The feed network includes multiple transceiver channels, each corresponding to a transceiver component. The signal generator generates radio frequency (RF) signals, and the preamplifier amplifies the RF signals before providing them to the feed network. The feed network provides RF signals from different transceiver channels to their respective transceiver components. Each transceiver component can independently provide RF signals to the radiating component, thereby enabling the radiating component to radiate electromagnetic waves. Additionally, the radiating component can receive external electromagnetic waves and transmit them through its corresponding transceiver component to the corresponding transceiver channel in the feed network, thus achieving multi-channel signal transmission and reception.

[0033] In summary, a radar consists of multiple channels for transmitting and processing signals. For example, each channel may include feed lines or input / output (I / O) circuits for signal transmission. Each channel may also include devices for signal amplification, frequency conversion, phase shifting, and analog-to-digital conversion (A / D conversion). Errors at any stage of signal propagation can cause channel inconsistencies, thus reducing radar performance.

[0034] In addition, as the industry continues to raise its requirements for communication capacity, signal transmission quality and transmission rate, the number of channels contained in radar is also increasing. Therefore, the problem of inconsistency between channels will become more prominent and will significantly reduce the performance of radar.

[0035] For example, with the development and advancement of sensor technology, the industry's pursuit of high resolution and other performance characteristics has made large-array radar increasingly popular. Large-array radar, as the name suggests, is a phased array radar system composed of a large number of radiating components. Large-array radar has many significant advantages. For instance, due to the use of numerous radiating components, large-array millimeter-wave radar possesses strong target resolution capabilities, enabling ultra-high spatial resolution. Furthermore, it has superior beamforming capabilities. During beam scanning, the direction of the radar beam can be rapidly changed by controlling the amplitude and phase of the radio frequency signal in each channel, achieving beamforming. Additionally, it possesses good flexibility and adaptability. Radars with electronic scanning capabilities can quickly adapt to different needs and avoid or reduce interference by adjusting the beam, exhibiting good anti-interference capabilities.

[0036] However, large-array millimeter-wave radars have more channels, each containing various types of devices. The non-ideal characteristics of these devices increase inconsistencies between channels, significantly impacting accurate signal processing. For example, amplitude and phase superposition between channels becomes impossible, hindering accurate beam scanning and high-resolution imaging.

[0037] Therefore, embodiments of this application provide a channel correction architecture that can effectively achieve channel consistency.

[0038] To make the objectives, technical solutions, and advantages of this application clearer, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0039] As shown in Figure 2, in one example provided in this application, the channel calibration architecture may include a signal generator, a preamplifier, a feed network, a scaler, and multiple transceiver components. The feed network has multiple transceiver channels, each corresponding to one of the transceiver components. The signal generator generates a calibration RF signal. The scaler is connected to the signal generator and receives the calibration RF signal generated by the signal generator. The preamplifier is connected between the signal generator and the scaler, and converts the calibration RF signal generated by the signal generator into an amplified signal.

[0040] During the calibration phase, the signal generator can produce the aforementioned calibration radio frequency signal. During the normal operating phase of the radar, the signal generator can also produce the radio frequency signal under normal operating conditions. To facilitate understanding of the technical solution of this application, the calibration phase will be used as an example for illustrative explanation below.

[0041] The signal generator is used to generate a calibration radio frequency signal, and the calibrator is used to generate a first correction coefficient based on the calibration radio frequency signal and the amplified signal. That is, the first correction coefficient can characterize the non-ideal characteristics of the preamplifier, thereby facilitating calibration.

[0042] Additionally, the scaler is connected to the feed network, where it transmits the calibration RF signal. The calibration RF signal is then transmitted from the feed network to each transceiver component, which generates a first echo signal based on the calibration RF signal. The feed network also transmits the first echo signal generated by each transceiver component to the scaler. The scaler then generates a second correction coefficient corresponding to each transceiver channel based on the calibration RF signal and each first echo signal.

[0043] That is, the second correction coefficient can characterize the irrational characteristics of the power supply network and signal transceiver components, thus facilitating correction.

[0044] It should be noted that, for ease of understanding of the technical solution of this application, the following example will be exemplified by achieving signal phase consistency between channels. In practical applications, this channel correction architecture can also achieve amplitude consistency, gain consistency, etc., between channels, which will not be elaborated here.

[0045] The calibration signal can be a radio frequency (RF) signal with known parameters such as phase and amplitude. When the calibration RF signal is amplified by a preamplifier, it may undergo distortion. For example, the phase of the calibration RF signal may be deflected. That is, the phase of the amplified signal and the calibration RF signal may differ.

[0046] In the example provided in this application, the calibrator can receive a calibration radio frequency signal and an amplified signal. By comparing the phase of the calibration radio frequency signal and the phase of the amplified signal, the phase difference between the calibration radio frequency signal and the amplified signal can be determined.

[0047] In addition, the scaler is also used to transmit the calibration RF signal to the feed network. The feed network has multiple channels, and the signal transmitted in each channel is transmitted to the corresponding transceiver component through multiple transceiver channels for signal transmission and reception.

[0048] When the calibration RF signal is transmitted through each channel in the feed network, its phase may be deflected, resulting in phase inconsistencies between the calibration RF signals transmitted from each transceiver channel to the corresponding transceiver component. Additionally, the calibration signal is transmitted and received in each transceiver component, generating a first echo signal. This first echo signal is transmitted to the feed network through the corresponding transceiver channel. The calibrator can compare the received first echo signal with the calibration RF signal to determine the phase difference between the two signals.

[0049] Specifically, in the example provided in Figure 2, three transceiver channels in the feeder network are shown: transceiver channel a, transceiver channel b, and transceiver channel c. Additionally, three transceiver components are also shown: transceiver component a, transceiver component b, and transceiver component c.

[0050] The calibration RF signal is transmitted from the calibrator to the power supply network and transmitted through transceiver channels a, b, and c respectively.

[0051] For example, the calibration RF signal is transmitted to transceiver component a through transceiver channel a of the feed network, and a first echo signal a is generated in transceiver component a. The first echo signal a is transmitted to the feed network through transceiver channel a, and finally to the calibrator. The calibrator can generate a second correction coefficient a based on the calibration RF signal and the first echo signal a.

[0052] Additionally, the calibration RF signal is transmitted to the transceiver component b via the transceiver channel b of the feed network, where a first echo signal b is generated. The first echo signal b is then transmitted back to the feed network via the transceiver channel b and finally to the calibrator. The calibrator can generate a second correction coefficient b based on the calibration RF signal and the first echo signal b.

[0053] Additionally, the calibration RF signal is transmitted to the transceiver component c via the transceiver channel c of the feed network, where a first echo signal c is generated. The first echo signal c is then transmitted back to the feed network via the transceiver channel c and finally to the calibrator. The calibrator can generate a second correction coefficient c based on the calibration RF signal and the first echo signal c.

[0054] In summary, the first correction coefficient characterizes the phase distortion of the calibration RF signal propagating in the preamplifier. The second correction coefficient 'a' characterizes the phase distortion of the signal (including the calibration RF signal and the first echo signal 'a') propagating between the feed network and the transceiver component 'a'. The second correction coefficient 'b' characterizes the phase distortion of the signal (including the calibration RF signal and the first echo signal 'b') propagating back and forth between the feed network and the transceiver component 'b'. The second correction coefficient 'c' characterizes the phase distortion of the signal (including the calibration RF signal and the first echo signal 'c') propagating back and forth between the feed network and the transceiver component 'c'. The first correction coefficient allows for phase correction of the amplified signal, ensuring that its phase is the same as the calibration RF signal. The second correction coefficients 'a', 'b', and 'c' facilitate correction of each channel, ensuring that the phases of the first echo signal 'a', 'b', 'c', and the calibration RF signal received by the calibrator are the same, ultimately achieving internal channel correction.

[0055] In one example, the signal generator can be a common device capable of generating radio frequency signals, such as an RF module or RF circuit. In practical applications, the type of signal generator can be appropriately selected according to actual needs.

[0056] In one example, the preamplifier may include circuits or devices capable of amplifying signals, such as amplifier circuits. In practical applications, the preamplifier can be of a commonly used type, and this application does not limit the specific type of preamplifier.

[0057] In one example, each transmit / receive channel in the power supply network may include devices such as phase shifters and amplifiers. That is, each transmit / receive channel has devices that can perform functions such as phase adjustment and amplitude adjustment of the signal.

[0058] In one example, the scaler may also include devices for adjusting the phase and amplitude of the signal. Alternatively, the scaler may include devices for quantitatively attenuating the signal to achieve effective matching between the scaler and the preamplifier and feed network. Or, in some examples, the scaler may also include circuitry or modules for performing data calculations to generate the first and second correction coefficients described above.

[0059] The calibrator can be connected to the preamplifier via a coupler to receive the amplified signal generated by the preamplifier. The coupler can be integrated into either the calibrator or the preamplifier; the specific placement of the coupler can be adjusted according to actual needs.

[0060] In one implementation, the signal generator can generate one type of calibration RF signal or multiple different types of calibration RF signals to obtain a first correction coefficient and a second correction coefficient with higher accuracy.

[0061] It should be noted that in practical applications, the calibrator may also have non-ideal characteristics, causing distortion of the calibration RF signal when it passes through the calibrator. Therefore, high-precision first and second correction coefficients can be obtained by using various types of calibration RF signals.

[0062] For example, a signal generator can produce a calibration RF signal, and a scaler can generate a first correction coefficient and a second correction coefficient based on the method described above. The signal generator can then produce another calibration RF signal, which has a different phase from the first calibration RF signal. The scaler can again generate the first correction coefficient and the second correction coefficient based on the method described above. Finally, multiple first correction coefficients are filtered or calculated to obtain more accurate first correction coefficients. Similarly, multiple second correction coefficients can be filtered or calculated to obtain more accurate second correction coefficients.

[0063] In practical applications, the number of times and type of calibration RF signals are generated can be reasonably selected and adjusted according to actual needs, which will not be elaborated here.

[0064] In addition, in one example provided in this application, the channel correction architecture may also have a temperature compensation function to adapt to effective correction under different ambient temperatures.

[0065] For example, as shown in Figure 3, in another example provided in this application, the channel correction architecture may also include a temperature sensor. The temperature sensor is used to detect the ambient temperature and generate a temperature detection signal.

[0066] The calibrator is connected to the temperature sensor to receive the temperature detection signal generated by the temperature sensor. Based on the temperature detection signal, the calibrator generates a first correction coefficient according to the temperature detection signal, the calibration RF signal, and the amplified signal. The calibrator also generates a second correction coefficient corresponding to each transceiver channel based on the temperature detection signal, the calibration RF signal, and each first echo signal.

[0067] For example, assuming the ambient temperature detected by the temperature sensor is 25°C, the calibrator can generate a first correction factor and a second correction factor based on 25°C.

[0068] Assuming the ambient temperature detected by the temperature sensor is 30°C, the calibrator can generate a first correction factor and a second correction factor based on 30°C.

[0069] In other words, the first and second correction coefficients generated by the calibrator are matched to the ambient temperature. Therefore, in practical applications, the corresponding first and second correction coefficients can be selected according to different ambient temperatures to achieve temperature compensation, thereby avoiding errors caused by temperature differences and achieving better channel calibration.

[0070] As shown in Figure 4, in one example, the channel correction architecture may further include a processor. The processor is connected to a scaler and a feed network. The processor generates a primary correction signal based on a first correction coefficient and a second correction coefficient generated by the scaler. The feed network adjusts the amplitude and phase of the calibrated RF signal according to the primary correction signal, ensuring that each first echo signal received by the scaler has the same phase.

[0071] Specifically, each transmit / receive channel in the power supply network can include devices such as phase shifters and amplifiers. In other words, each transmit / receive channel has devices capable of adjusting the phase and amplitude of the signal. Therefore, the phase shifter in each channel of the power supply network can independently adjust the phase of the signal transmitted within that channel.

[0072] For example, assuming the phase of the calibration RF signal is θ0, and the phase of the first echo signal a received by the calibrator is θ1, then the second correction coefficient a can be θ0 / θ1. During calibration, the processor can generate a primary correction signal a based on this second correction coefficient a. The phase shifter in the feed network can adjust the phase of the calibration RF signal and / or the first echo signal a based on this primary correction signal a, so that the phase of the first echo signal a received by the calibrator is θ0.

[0073] Assuming the phase of the calibration RF signal is θ0, and the phase of the first echo signal b received by the calibrator is θ2, then the second correction coefficient b can be θ0 / θ2. During calibration, the processor can generate a primary correction signal b based on this second correction coefficient b. The phase shifter in the feed network can adjust the phase of the calibration RF signal and / or the first echo signal b based on this primary correction signal b, so that the phase of the first echo signal b received by the calibrator is θ0.

[0074] Assuming the phase of the calibration RF signal is θ0, and the phase of the first echo signal c received by the calibrator is θ3, then the second correction coefficient c can be θ0 / θ3. During calibration, the processor can generate a primary correction signal c based on this second correction coefficient c. The phase shifter in the feed network can adjust the phase of the calibration RF signal and / or the first echo signal c based on this primary correction signal c, so that the phase of the first echo signal c received by the calibrator is θ0.

[0075] In summary, the processor can send a correction signal to the phase shifter in the feed network based on the second correction coefficient generated by the scaler. The phase shifter adjusts the phase of the calibration RF signal and / or the first echo signal based on the correction signal so that the phase of the first echo signal received by the scaler is the same as the phase of the calibration RF signal.

[0076] The overall process of channel calibration can be roughly divided into:

[0077] 1. Generation of calibration RF signal. The signal generator generates a calibration RF signal, and this calibration RF signal is a signal with known parameters such as phase and amplitude.

[0078] 2. Signal transmission and reception. This specifically includes the transmission of the calibration RF signal in the preamplifier, scaler, power supply network, and transceiver components. It also includes the transmission of the first echo signal in the transceiver components, power supply network, and scaler. This is used to detect signal distortion that occurs during transmission.

[0079] 3. Signal processing and analysis. This specifically includes the comparison and analysis of the calibration RF signal and the amplified signal. It also includes the comparison and analysis of the calibration RF signal and the first echo signal. This is to determine the distortion that occurs in the signal during transmission.

[0080] 4. Calculation of correction coefficients. This includes calculating the first correction coefficient based on the detection results of the calibration RF signal and the amplified signal. It also includes calculating the second correction coefficient based on the detection results of the calibration RF signal and the first echo signal.

[0081] 5. Channel Correction. The distortion of the signal during transmission in the channel is obtained by calculating the first and second correction coefficients, and then corrected to compensate for changes in parameters such as amplitude and phase.

[0082] 6. Verification and Testing. Verify the effectiveness and accuracy of the calibration through multiple tests to ensure that the consistency between channels meets design requirements.

[0083] In the example above, the correction involved is performed when the signal is transmitted within the system. That is, the radio frequency signal generates a first echo signal in the transceiver components, but no actual electromagnetic wave radiation is achieved.

[0084] In practical applications, in order to realize the wireless transmission function of signals in radar systems, the radiation and reception of electromagnetic waves in the space environment (such as air interface transmission) are also involved. Furthermore, electromagnetic waves will be distorted when passing through radiation components and propagating in the space environment, thus affecting the consistency between channels.

[0085] Therefore, in another example provided in this application, based on the above example, the channel correction architecture can also effectively correct the distortions generated by electromagnetic waves during radiation and reception by configuring other correction circuits. That is, the channel correction architecture can first perform internal correction and then perform external correction.

[0086] Specifically, as shown in Figure 5, in one example provided in this application, the channel correction architecture further includes multiple radiating components, a receiver, and a correction circuit. Specifically, Figure 5 shows three radiating components: radiating component a, radiating component b, and radiating component c. Each radiating component may include at least one radiating element, which can transmit and receive electromagnetic waves, thereby achieving wireless signal transmission and reception capabilities. The radiating element can be of single-polarization or dual-polarization type, etc. In specific applications, the specific type and number of radiating elements can be reasonably configured according to actual needs; this application does not impose any restrictions on this.

[0087] Multiple radiating components are connected one-to-one with multiple transceiver components. The radiating components are used to radiate electromagnetic waves to the target object and receive the second echo signal reflected from the target object. Specifically, the target object can be a metal plate or a metal sphere, or other objects that can achieve a strong signal-to-noise ratio (SNR).

[0088] For example, as shown by the solid arrow in Figure 5, the calibration RF signal generated by the signal generator is amplified by a preamplifier and transmitted to the feed network. It is then transmitted through the transmit / receive channel a of the feed network to the transceiver assembly a, and then radiated as electromagnetic waves by the radiating assembly a. After reflection from the target object, the electromagnetic waves are received by the radiating assembly a as a second echo signal a. The second echo signal a is received by the transceiver assembly a and transmitted to the feed network through the transmit / receive channel a. Furthermore, the second echo signal a is amplified by a preamplifier and transmitted to the receiver, thus achieving the reception of the second echo signal a. Additionally, a correction circuit is connected to the receiver and is used to generate a third correction coefficient a based on the second echo signal a and the calibration RF signal.

[0089] Additionally, the calibration RF signal is transmitted to transceiver component b via transceiver channel b of the feed network, and then radiated as electromagnetic waves by radiating component b. After reflection from the target object, the electromagnetic waves are received by radiating component b as a second echo signal b. The second echo signal b is received by transceiver component b and transmitted to the feed network via transceiver channel b. Furthermore, the second echo signal b is amplified by a preamplifier before being transmitted to the receiver, thus achieving reception of the second echo signal b. Additionally, a correction circuit is connected to the receiver, and this circuit generates a third correction coefficient b based on the second echo signal b and the calibration RF signal.

[0090] Additionally, the calibration RF signal is transmitted to the transceiver component c via the transceiver channel c of the feed network, and then radiated as electromagnetic waves by the radiating component c. After reflection from the target object, the radiating component c receives the second echo signal c. The second echo signal c is received by the transceiver component c and transmitted to the feed network via the transceiver channel c. Furthermore, the second echo signal c is amplified by a preamplifier before being transmitted to the receiver, thus achieving reception of the second echo signal c. A correction circuit is connected to the receiver and is used to generate a third correction coefficient c based on the second echo signal c and the calibration RF signal.

[0091] In summary, the third correction factor 'a' characterizes the phase distortion of the signal during propagation through radiating component a, the target object, and the receiving component a. The third correction factor 'b' characterizes the phase distortion of the signal during propagation through radiating component b, the target object, and the receiving component b. The third correction factor 'c' characterizes the phase distortion of the signal during propagation through radiating component c, the target object, and the receiving component c. These third correction factors 'a', 'b', and 'c' facilitate the correction of each channel, ensuring that the phases of the second echo signals 'a', 'b', and 'c' received by the receiver are the same as the calibration RF signal, ultimately achieving external channel correction.

[0092] In addition, the processor is used to generate a secondary correction signal based on the third correction coefficient, and the feed network is used to adjust the amplitude and phase of the second echo signal based on the secondary correction signal so that the phase and amplitude of each second echo signal received by the receiver are the same.

[0093] For example, assuming the phase of the calibration RF signal is θ0, and the phase of the second echo signal a received by the receiver is θ1, then the third correction coefficient a can be θ0 / θ1. During correction, the processor can generate a secondary correction signal a based on this third correction coefficient a. The phase shifter in the feed network can adjust the phase of the calibration RF signal and / or the second echo signal a based on this secondary correction signal a, so that the phase of the second echo signal a received by the calibrator is θ0.

[0094] Assuming the phase of the calibration RF signal is θ0, and the phase of the second echo signal b received by the receiver is θ2, then the third correction coefficient b can be θ0 / θ2. During correction, the processor can generate a secondary correction signal b based on this third correction coefficient b. The phase shifter in the feed network can adjust the phase of the calibration RF signal and / or the second echo signal b based on this secondary correction signal b, so that the phase of the second echo signal b received by the receiver is θ0.

[0095] Assuming the phase of the calibration RF signal is θ0, and the phase of the second echo signal c received by the receiver is θ3, then the third correction coefficient c can be θ0 / θ3. During correction, the processor can generate a secondary correction signal c based on this third correction coefficient c. The phase shifter in the feed network can adjust the phase of the calibration RF signal and / or the second echo signal c based on this secondary correction signal c, so that the phase of the second echo signal c received by the receiver is θ0.

[0096] In summary, the processor can send a secondary correction signal to the phase shifter in the feed network based on the generated third correction coefficient. The phase shifter then adjusts the phase of the calibration RF signal or the second echo signal according to this secondary correction signal, ensuring that the phase of the second echo signal received by the receiver is the same as the phase of the calibration RF signal. External correction can effectively correct errors caused by air interface transmission, radiating component coupling, etc. Furthermore, the waveform of the calibration RF signal can be reasonably adjusted according to actual needs to improve the signal-to-noise ratio of target detection and reduce the effects of coupling between adjacent channels, thereby achieving better correction accuracy.

[0097] In one example, the preamplifier may include a circulator, and the receiver is connected to the circulator in the preamplifier. The preamplifier amplifies the second echo signal and then transmits it to the receiver through the circulator.

[0098] In one example, the correction circuit may include circuitry or modules for performing data calculations to generate the aforementioned third correction coefficient. In practice, the specific type of correction circuit can be appropriately configured according to actual needs, and this application does not impose any limitations on this.

[0099] In one implementation, single-channel sequential calibration or multi-channel simultaneous calibration can be used.

[0100] To enable all channels to transmit waveforms in a shorter time, the transmitted waveforms need to be optimized.

[0101] For example, please refer to Figure 6. In one example, fast time-division multiplexing (DDM) and time-division multiplexing (TDM) sequences can be generated between transmit channels. Specifically, frequency division multiplexing (DDM) and time division multiplexing (TDM) can be used to encode the waveforms. The waveform type encoded by DDM is strongly correlated with the phase shifter; typically, a 90-degree DDM encoded waveform can be used. All transmit channels are encoded into a single transmit timing unit (e.g., a transmit sequence) in DDM format. For example, when there are M channels, the M channels can be divided into N groups, each containing m channels. Here, m = M / N. In each group, m Tx signals are transmitted simultaneously in the DDM-encoded sequence. After transmission, the remaining groups are then transmitted in the same manner using TDM encoding. The DDM-encoded transmit waveforms are then transmitted to the target object via a transmit antenna (e.g., a radiating element). The receive antenna receives the echo reflected from the target object. The received echo is a mixed echo, and each receive channel needs to perform de-DDM decoding on the received echo through a matched filter. That is, the Doppler dimension decoding operation is performed sequentially by m transmitted waveform angle codewords, the m transmitted and received channels in each group are rearranged, and the echoes in each TDM group are processed and then rearranged uniformly, thereby shortening the transmission waveform time.

[0102] Alternatively, in another example, to improve transmission efficiency and power, the waveform can be encoded using code division multiplexing (CDM). This generates fast time-dimension CDM code division and time-dimension combined sequences across multiple transmission channels, i.e., waveforms encoded using both CDM and TDM. The types of waveforms encoded using CDM are related to the orthogonal codeword sequence.

[0103] Please refer to Figure 7. All transmit channels are encoded into a single transmission timing unit (e.g., a transmission sequence) using m Tx codes in CDM format. Since CDM encoding exhibits orthogonality, each group of m Tx codes can be transmitted simultaneously after CDM encoding. After transmission, the remaining groups are sequentially transmitted using the same timing TDM encoding method, and the waveforms are transmitted to the target object via a transmitting antenna (e.g., a radiating element). The receiving antenna receives the echo reflected from the target object; the received echo is a mixed echo. Each receiving channel requires a matching filter to perform CDM decoding on the received echo. That is, the code-division dimension decoding operation is performed sequentially using the m transmitted waveform angle codewords, the m transmit and receive channels within each group are rearranged, and then the echoes within each TDM group are processed and uniformly rearranged.

[0104] The rearranged channel data can be processed by following the operation procedure shown in Figure 8 to calculate the frequency offset error and phase offset error.

[0105] The frequency offset error calculation involves calculating the frequency offset information of the detected echo. This is done by performing an autocorrelation function on the echo signal of each channel, obtaining the position of the peak point P_peak in the autocorrelation function, and then calculating the deviation of the peak point from the data center position P_dev1, resulting in P_dev1 = P_peak - fft_num / 2. Simultaneously, the unit frequency offset is calculated, i.e., each unit offset df is calculated as df = Fs / fft_num, where Fs is the sampling rate of the entire sampling system, and fft_num is the number of points in the Fourier Transform (FFT) of the echo. From this, the frequency offset error P_dev2 = P_dev1 * df can be calculated, and subsequent compensation is performed using a frequency offset compensation method.

[0106] Phase offset error calculation: For the target signal after frequency offset compensation, which is a complex signal t=a+b*j, the phase error t_com is calculated.

[0107] Where t_com = sqrt(a^2 + b^2) / (a ​​+ b * j), compensation is subsequently performed by constructing a phase offset compensation method.

[0108] Error correction compensation can be achieved by completing frequency offset error and phase offset compensation. By performing the above operations on all channels of the array, channel amplitude and phase consistency correction can be achieved.

[0109] It is understandable that other encoding forms or calculation methods can be used to process signals in practical applications, which will not be elaborated here.

[0110] In summary, in practical applications, a receiver can include multiple receiving channels, and the combined wave can be transmitted to a data shaper through these channels. The data shaper is used for data storage, such as channel arrangement according to a data rule. The storage protocol and the parsing protocol are corresponding.

[0111] In practical applications, the aforementioned channel correction architecture can be used in communication equipment such as radar and array antennas.

[0112] Alternatively, in one example, radar could be a communication device used to transmit signals, or it could be a device used for security checks.

[0113] For example, large-array security radar typically refers to an array composed of multiple antenna elements that electronically control beam scanning to achieve rapid and accurate target detection. This technology has broad application prospects in the security inspection field, especially in improving the efficiency and accuracy of security checks.

[0114] Security radar technology utilizes millimeter-wave electromagnetic waves for detection and imaging, offering significant advantages in security inspections. This technology can penetrate clothing to generate a three-dimensional image of the person being inspected, thereby detecting various contraband and smuggled goods, including both metallic and non-metallic items. Compared to traditional metal detector gates or handheld metal detectors, millimeter-wave security scanners provide more comprehensive security checks while avoiding direct physical contact with the person being inspected, thus improving efficiency and comfort.

[0115] Of course, millimeter-wave radar technology also has wide applications in other fields, such as autonomous vehicles, security monitoring, and weather forecasting. In the field of autonomous driving, millimeter-wave radar can perform obstacle detection, vehicle positioning, and environmental perception, making it one of the core sensors in Advanced Driver Assistance Systems (ADAS) and autonomous driving systems. In the field of security monitoring, millimeter-wave radar can be used to monitor activities around buildings, identify potential intruders, and achieve real-time monitoring and security protection of areas. In the field of weather forecasting, millimeter-wave radar can monitor atmospheric parameters such as humidity, precipitation, and cloud cover, improving the accuracy of weather forecasts.

[0116] Overall, the development of millimeter-wave security radar technology has not only improved the efficiency and security of security checks, but also supported technological advancements in other fields. With the continuous maturation of the technology and the expansion of its application scenarios, millimeter-wave radar technology is expected to play an even more important role in the future.

[0117] Radar channel calibration is a crucial technique for ensuring radar system performance. It involves compensating for various inconsistencies in the radar's receiving and transmitting channels. These inconsistencies may arise from differences in hardware components, variations in ambient temperature, and other factors. The purpose of calibration is to improve the radar system's target detection capability, resolution, and measurement accuracy.

[0118] Due to their large size, large-array security inspection radars cannot be calibrated as a whole in a darkroom.

[0119] Therefore, in the example provided in this application, internal calibration can be achieved by adopting the aforementioned channel correction architecture. External parameter calibration can also be achieved in experimental scenarios. In summary, the internal calibration process utilizes the radar system's internal circuitry and calibrators to measure the relative changes in amplitude and phase of various system components during imaging. During external parameter calibration, the transmitted waveform differs from the operational waveform; a specific transmitted waveform is typically required to improve the target scattering signal-to-noise ratio, thereby effectively acquiring the scattering information of the calibrated target.

[0120] In one example, when security radar is applied in security inspection equipment, the security inspection equipment may include one or more of the aforementioned security radars, which will not be elaborated here.

[0121] In the various embodiments of this application, unless otherwise specified or in case of logical conflict, the terminology and / or descriptions of different embodiments are consistent and can be referenced by each other. The technical features of different embodiments can be combined to form new embodiments according to their inherent logical relationship.

[0122] In this application, "multiple" means two or more. "And / or" describes the relationship between related objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist simultaneously, or B exists alone, where A and B can be singular or plural.

[0123] It is understood that the various numerical designations used in the embodiments of this application are merely for descriptive convenience and are not intended to limit the scope of the embodiments of this application. The order of the process numbers described above does not imply the order of execution; the execution order of each process should be determined by its function and internal logic.

Claims

1. A lane correction architecture, characterized by, It includes a power supply network and multiple transceiver components, wherein the power supply network has multiple transceiver channels, and the multiple transceiver channels are connected one-to-one with the multiple transceiver components; The channel correction architecture also includes: A signal generator is used to generate calibration radio frequency signals; A calibrator, connected to the signal generator, is used to receive the calibration radio frequency signal generated by the signal generator; A preamplifier is connected between the signal generator and the scaler, and the preamplifier is used to convert the calibrated radio frequency signal generated by the signal generator into an amplified signal. The calibrator is used to generate a first correction coefficient based on the calibration radio frequency signal and the amplified signal; The calibrator is also connected to the feed network, and the calibrator is used to transmit the calibration radio frequency signal to the feed network; The calibration radio frequency signal is transmitted by the feed network to each of the transceiver components, and each of the transceiver components is used to generate a first echo signal based on the calibration radio frequency signal. The power supply network is also used to transmit the first echo signal generated by each of the transceiver components to the scaler. The calibrator is used to generate a second correction coefficient corresponding to each of the transceiver channels based on the calibration RF signal and each of the first echo signals.

2. The channel correction architecture of claim 1, wherein, The calibration radio frequency signal is a radio frequency signal with known amplitude and phase.

3. The channel correction architecture of claim 1 or 2, wherein, The channel calibration architecture also includes a temperature sensor; The temperature sensor is used to detect the ambient temperature and generate a temperature detection signal; The calibrator is used to generate a first correction coefficient based on the temperature detection signal, the calibration radio frequency signal, and the amplified signal; The calibrator is further configured to generate a second correction coefficient corresponding to each of the transceiver channels based on the temperature detection signal, the calibration radio frequency signal, and each of the first echo signals.

4. The channel correction architecture of any one of claims 1 to 3, wherein, The channel correction architecture also includes a processor connected to the scaler and the power supply network; The processor is used to generate a correction signal based on the first correction coefficient and the second correction coefficient; The power supply network is used to adjust the amplitude and phase of the calibration radio frequency signal according to the primary correction signal, so that the phase and amplitude of each first echo signal received by the calibrator are the same.

5. The passageway correction architecture of claim 4, wherein, The channel correction architecture also includes multiple radiation components, receivers, and correction circuitry; The plurality of radiation components are connected one-to-one with the plurality of transceiver components. The plurality of radiation components are used to radiate electromagnetic waves toward the target and receive the second echo signal reflected from the target. The preamplifier is also connected to the receiver and the power supply network; The second echo signal is transmitted to the receiver after passing through the feed network and the preamplifier; The correction circuit is connected to the receiver and is used to generate a third correction coefficient based on the calibration RF signal and the second echo signal of each of the transceiver channels.

6. The channel correction architecture of claim 5, wherein, The processor is configured to generate a secondary correction signal according to the third correction coefficient, and the feed network is configured to adjust the amplitude and phase of the second echo signal according to the secondary correction signal, so that the phase and amplitude of each second echo signal received by the receiver are the same.

7. The channel correction architecture of claim 5 or 6, wherein, The receiver is connected with a circulator in the preamplifier.

8. The passageway correction architecture of any one of claims 1 to 7, wherein, The calibrator is connected with the preamplifier through a coupler.

9. A radar, characterized by A channel correction architecture according to any one of claims 1 to 8.

10. A security screening apparatus, characterized in that, A radar according to claim 9.

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