Plasma spectrum expansion effect equivalent radar cross section calibration system and method

Abstract

The invention relates to a plasma spectrum spreading effect equivalent radar cross section calibration system and method, wherein a wind tunnel in the system is used to form a detonation test environment by using high-speed test gas filled by a high-speed airflow generating device; a transceiver for antenna direct leakage echo calibration is used to obtain background echo data and preset calibration body echo data in the wind tunnel through a signal transmission module, and send them to a calibration module; a transceiver for plasma spectrum spreading effect signal echo calibration is used to obtain echo data of a target to be measured in the wind tunnel under a detonation test environment through a signal transmission module, and send them to a calibration module; and a calibration module is used to determine the equivalent radar cross section of the plasma spectrum spreading effect signal echo of the target to be measured at a preset measurement frequency.

Description

Technical Field

[0001] The invention relates to the technical field of signal processing, and in particular to a plasma spectrum expansion effect equivalent radar cross section calibration system and method. Background Art

[0002] The plasma spectrum expansion effect refers to the spectrum modulation phenomenon caused by the plasma sheath formed by the friction between the high-speed target (such as a satellite, a return capsule or a spacecraft to be recovered, etc.) and the atmosphere, and the plasma sheath produces spectrum modulation on the irradiated electromagnetic waves. This phenomenon is simulated on the ground by having a high-speed airflow hit the target to be measured to generate a plasma sheath, and the measurement equipment generates a measurement signal to illuminate the target to be measured, and the broadband echo signal is recorded to obtain the plasma frequency expansion effect phenomenon data. The radar cross section (RCS) is an important scattering feature of the target. Based on this feature, it can be determined whether the target to be measured can be detected by radar. Specifically, the higher the radar cross section of the target, the easier it is to detect the target. On the contrary, the target is less likely to be detected.

[0003] The traditional plasma spectrum spreading effect measurement system and measurement process can only obtain the echo power of the plasma spectrum spreading effect of the target to be measured, and cannot be quantified into an equivalent RCS.

[0004] Therefore, in view of the above shortcomings, this invention is specially proposed. Summary of the invention

[0005] The technical problem to be solved by the present invention is how to realize the equivalence of the plasma spectrum expansion effect signal echo of the target to be measured to the radar scattering cross section. In view of the defects in the prior art, a plasma spectrum expansion effect equivalent radar scattering cross section calibration system and method are provided.

[0006] In order to solve the above technical problems, the present invention provides a plasma spectrum spreading effect equivalent radar cross section calibration system, comprising a wind tunnel, a high-speed airflow generating device, a signal transmission module, a transceiver for antenna direct leakage echo calibration, a transceiver for plasma spectrum spreading effect signal echo calibration and a calibration module, wherein:

[0007] The high-speed airflow generating device is used to fill the wind tunnel with high-speed test gas;

[0008] The wind tunnel is used to form a detonation test environment by using the high-speed test gas filled therein;

[0009] The antenna direct leakage echo calibration transceiver is used to send a first measurement signal into the wind tunnel through the signal transmission module, and obtain background echo data and preset standard echo data in the wind tunnel, and send the background echo data and the preset standard echo data to the calibration module, wherein the background echo data includes antenna direct leakage echo data;

[0010] The plasma spectrum spreading effect signal echo calibration transceiver module is used to send a second measurement signal to the wind tunnel under the detonation experiment environment through the signal transmission module, and obtain the echo data of the target to be measured in the wind tunnel under the detonation experiment environment, and send the echo data of the target to be measured to the calibration module, wherein the frequency of the second measurement signal is the same as the center frequency of the first measurement signal, and both are preset measurement frequencies;

[0011] The calibration module is used to determine the equivalent radar cross-section of the antenna direct leakage echo according to the background echo data and the preset calibration body echo data, and to determine the equivalent radar cross-section of the plasma spectrum spreading effect signal echo of the target to be measured at the preset measurement frequency according to the equivalent radar cross-section of the antenna direct leakage echo and the echo data of the target to be measured.

[0012] Preferably, the antenna direct leakage echo calibration transceiver device includes a vector network analyzer, which is used to generate the first measurement signal and send it through the signal transmission module. The vector network analyzer is also used to obtain the background echo data and the preset calibration body echo data through the signal transmission module, and send the background echo data and the preset calibration body echo data to the calibration module.

[0013] Preferably, the plasma spectrum spreading effect signal echo calibration transceiver module comprises a signal source and a spectrum analyzer, wherein:

[0014] The signal source is used to generate the second measurement signal and send it through the signal transmission module; the spectrum analyzer is used to obtain the echo data of the target to be measured through the signal transmission module, and send the echo data of the target to be measured to the calibration module.

[0015] Preferably, the high-speed airflow generating device and the spectrometer are configured to synchronously trigger a signal after the signal source sends the second measurement signal, so that when the high-speed airflow generating device fills the wind tunnel with high-speed test gas, the spectrometer starts to acquire the echo data of the target to be measured.

[0016] Preferably, the signal transmission module includes a transceiver antenna and a bridge / circulator, wherein the bridge / circulator and the transceiver antenna are used to sequentially receive and send measurement signals, and the transceiver antenna and the bridge / circulator are used to sequentially receive and send echo signals, wherein the measurement signal includes the first measurement signal and the second measurement signal, and the echo signal includes the background echo data, the preset marker echo data and the target echo data.

[0017] Preferably, the center frequency of the vector network analyzer is set to a preset measurement frequency, the signal bandwidth is set to any bandwidth value in the interval [1GHz, 4GHz], the number of sampling points is set to any integer number of points in the interval [101, 401], and the transmitting port and receiving port of the vector network analyzer are set to the same port.

[0018] Preferably, the transmission power of the signal source is set to a preset transmission power, and the transmission frequency is set to the preset measurement frequency; the receiving bandwidth of the spectrum analyzer is set to any bandwidth value in the range of [1MHz, 5MHz], and the resolution is set to any resolution value in the range of [1kHz, 5kHz].

[0019] Preferably, the calibration module is used for:

[0020] Performing vector subtraction processing on the preset target echo data and the background echo data to obtain vector subtraction data;

[0021] Performing one-dimensional range image interception and time-frequency transformation processing on the vector subtraction data to obtain preset marker echo power data;

[0022] Performing one-dimensional range image interception and time-frequency transformation processing on the background echo data to obtain first antenna direct leakage echo power data;

[0023] Based on the following formula, the equivalent radar cross section of the antenna direct leakage echo is determined;

[0024] C A =A-C+σ;

[0025] Among them, C A is the equivalent radar scattering cross section of the antenna direct leakage echo, A is the power data of the first antenna direct leakage echo, C is the power data of the preset calibration body echo, and σ is the equivalent radar scattering cross section of the known calibration body echo.

[0026] Preferably, the calibration module is also used for:

[0027] Determine the second antenna direct leakage echo power data and the target plasma spectrum spreading effect signal echo power data in the target echo data, wherein, in the target echo data, the frequency data at the preset measurement frequency position is the second antenna direct leakage echo power data, and the frequency data at other frequency positions is the target plasma spectrum spreading effect signal echo power data;

[0028] Based on the following formula, the equivalent radar cross section of the echo of the plasma spectrum spreading effect signal of the target to be measured is determined;

[0029] C F =F-A'+C A ;

[0030] Among them, C F is the equivalent radar scattering cross section of the plasma spectrum expansion effect signal echo of the target to be measured, F is the echo power data of the plasma spectrum expansion effect signal of the target to be measured; A' is the direct leakage echo power data of the second antenna; C A is the equivalent radar cross section of the antenna direct leakage echo.

[0031] The present invention also provides a plasma spectrum spreading effect equivalent radar cross section calibration method, which is performed by any of the plasma spectrum spreading effect equivalent radar cross section calibration systems described above, comprising:

[0032] Setting a preset standard body in the measurement area of ​​the wind tunnel;

[0033] The antenna direct leakage echo calibration transceiver sends a first measurement signal to the preset standard body through the signal transmission module, and obtains the preset standard body echo data;

[0034] removing the preset standard from the wind tunnel;

[0035] The antenna direct leakage echo calibration transceiver sends the first measurement signal to the wind tunnel through the signal transmission module, and obtains background echo data in the wind tunnel, wherein the background echo data includes antenna direct leakage echo data;

[0036] The antenna direct leakage echo calibration transceiver sends the preset calibration body echo data and the background echo data to the calibration module;

[0037] The target to be measured is set in the measuring area of ​​the wind tunnel, and the wind tunnel is set to a vacuum environment;

[0038] The high-speed airflow generating device emits high-speed test gas to the target to be measured, forming a detonation experimental environment in the wind tunnel; at the same time, the plasma spectrum spreading effect signal echo calibration transceiver module sends a second measurement signal to the target to be measured in the detonation experimental environment through the signal transmission module, and obtains the echo data of the target to be measured in the detonation experimental environment, and sends the echo data of the target to be measured to the calibration module, wherein the frequency of the second measurement signal is the same as the center frequency of the first measurement signal, and both are preset measurement frequencies;

[0039] The calibration module determines the equivalent radar cross section of the antenna direct leakage echo according to the background echo data and the preset calibration body echo data, and determines the equivalent radar cross section of the plasma spectrum spreading effect signal echo of the target to be measured at the preset measurement frequency according to the equivalent radar cross section of the antenna direct leakage echo and the echo data of the target to be measured.

[0040] The plasma spectrum expansion effect equivalent radar cross section calibration system and method of the present invention have the following beneficial effects:

[0041] By setting a transceiver for calibration of antenna direct leakage echo, background echo data including antenna direct leakage echo data and preset calibration body echo data in the wind tunnel are obtained; by setting a calibration module, the equivalent radar scattering cross section of the antenna direct leakage echo is determined according to the background echo data and the preset calibration body echo data; by setting a transceiver for calibration of plasma spectrum expansion effect signal echo, the echo data of the target to be measured in the wind tunnel under the detonation experimental environment are obtained; by using the calibration module, the equivalent radar scattering cross section of the plasma spectrum expansion effect signal echo of the target to be measured is determined according to the equivalent radar scattering cross section of the antenna direct leakage echo and the echo data of the target to be measured, so that the plasma spectrum expansion effect signal echo of the target to be measured is equivalent to the radar scattering cross section. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 It is a structural schematic diagram of a plasma spectrum spreading effect equivalent radar cross section calibration system provided in Embodiment 1 of the present invention;

[0043] Figure 2 It is a flow chart of a method for calibrating equivalent radar cross section of plasma spectrum spreading effect provided in the second embodiment of the present invention;

[0044] In the figure: 1: wind tunnel; 2: high-speed airflow generating device; 3: signal transmission module; 4: transceiver for calibration of antenna direct leakage echo; 5: transceiver module for calibration of plasma spectrum spreading effect signal echo; 6: calibration module; 31: transceiver antenna; 32: bridge / circulator; 41: vector network analyzer; 51: signal source; 52: spectrum analyzer. DETAILED DESCRIPTION

[0045] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0046] Embodiment 1

[0047] like Figure 1 As shown, the plasma spectrum spreading effect equivalent radar cross section calibration system provided by the embodiment of the present invention comprises a wind tunnel 1, a high-speed airflow generating device 2, a signal transmission module 3, a transceiver device for antenna direct leakage echo calibration 4, a transceiver module for plasma spectrum spreading effect signal echo calibration 5 and a calibration module 6, wherein:

[0048] The high-speed airflow generating device 2 is used to fill the wind tunnel 1 with high-speed test gas;

[0049] Wind tunnel 1 is used to form a detonation test environment by using high-speed test gas filled in;

[0050] The wind tunnel 1 in this embodiment has no special requirements for the default experimental environment. When a detonation experimental environment is required, the experimental environment of the wind tunnel 1 is set to a vacuum environment, and the high-speed airflow generating device 2 is turned on to fill the wind tunnel 1 with high-speed test gas. The speed of the high-speed test gas is Mach, and for example, the speed of the high-speed test gas is Mach 10.

[0051] The antenna direct leakage echo calibration transceiver 4 is used to send a first measurement signal into the wind tunnel 1 through the signal transmission module 3, and obtain background echo data and preset standard body echo data in the wind tunnel 1, and send the background echo data and the preset standard body echo data to the calibration module, wherein the background echo data includes the antenna direct leakage echo data; it can be understood that the process of obtaining the background echo data and the preset standard body echo data has no special requirements for the experimental environment of the wind tunnel 1.

[0052] Specifically, a preset calibration body is installed in the measurement area of ​​the wind tunnel 1, and a first measurement signal is sent to the wind tunnel 1 through the signal transmission module 3 using the antenna direct leakage echo calibration transceiver 4, and the corresponding preset calibration body echo data is obtained. The preset calibration body is removed from the measurement area of ​​the wind tunnel 1, and a first measurement signal is sent to the wind tunnel 1 through the signal transmission module 3 using the antenna direct leakage echo calibration transceiver 4, and the corresponding background echo data is obtained. Optionally, the preset calibration body can be a metal ball. The first measurement signal is preferably a broadband signal. The preset calibration body echo data and the background echo data are both complex number array strings in the frequency domain. The antenna direct leakage echo data is the data corresponding to the antenna direct leakage echo signal, and the antenna direct leakage echo signal is a signal that directly enters the receiver due to the reflected wave caused by the standing wave at the antenna port during the signal transmission process. The antenna direct leakage echo calibration transceiver 4 and the signal transmission module 3 can be connected by a measurement cable, wherein the measurement cable can be a microwave cable.

[0053] The plasma spectrum spreading effect signal echo calibration transceiver module 5 is used to send a second measurement signal to the wind tunnel 1 under the detonation experiment environment through the signal transmission module 3, and obtain the echo data of the target to be measured in the wind tunnel under the detonation experiment environment, and send the echo data of the target to be measured to the calibration module 6, wherein the frequency of the second measurement signal is the same as the center frequency of the first measurement signal, and both are preset measurement frequencies;

[0054] Preferably, after the antenna direct leakage echo calibration transceiver 4 obtains the background echo data and the preset calibration body echo data, the target to be measured is installed in the measurement area of ​​the wind tunnel 1, and the experimental environment of the wind tunnel 1 is set to a vacuum environment. The high-speed airflow generating device 2 is turned on to fill the wind tunnel 1 with high-speed test gas, so that the target to be measured in the wind tunnel 1 reacts with the high-speed test gas to generate a plasma sheath, forming a detonation experimental environment. At the same time, the plasma spectrum spreading effect signal echo calibration transceiver module 5 sends a second measurement signal to the target to be measured, and obtains the echo data of the target to be measured in the wind tunnel under the detonation experimental environment. It should be noted that, since the plasma spectrum spreading effect signal echo calibration transceiver module 5 continuously transmits the second measurement signal, when it starts to transmit the second measurement signal, the environment in the wind tunnel 1 can be a vacuum environment or a detonation experimental environment, which is not specifically limited here, but the echo data of the target to be measured received by the plasma spectrum spreading effect signal echo calibration transceiver module 5 must be under the detonation experimental environment.

[0055] The target to be measured is a head model of a load, wherein the load may be a satellite, a spacecraft, a return capsule, etc. The echo number of the target to be measured is a complex array string in the frequency domain. The plasma spectrum spreading effect signal echo calibration transceiver module 5 and the signal transmission module 3 may be connected by a measurement cable, wherein the measurement cable may be a microwave cable.

[0056] The calibration module 6 is used to determine the equivalent radar cross-section of the antenna direct leakage echo based on the background echo data and the preset calibration body echo data, and to determine the equivalent radar cross-section of the plasma spectrum expansion effect signal echo of the target to be measured at the preset measurement frequency based on the equivalent radar cross-section of the antenna direct leakage echo and the echo data of the target to be measured.

[0057] Preferably, the calibration module 6 can be specifically used to perform vector subtraction processing on the preset calibration body echo data and the background echo data to obtain vector subtraction data;

[0058] Perform one-dimensional range image interception and time-frequency transformation processing on the vector subtraction data to obtain the preset marker echo power data;

[0059] Preferably, the vector subtraction data can be converted into time domain data through one-dimensional range image processing. Based on the time domain data, the time domain data corresponding to the clutter signal and the time domain data corresponding to the preset marker can be distinguished; the time domain data corresponding to the preset marker is obtained through interception processing; and the preset marker echo power data is obtained through time-frequency transformation.

[0060] Perform one-dimensional range image interception and time-frequency transformation processing on the background echo data to obtain the first antenna direct leakage echo power data;

[0061] Preferably, the background echo data can be converted into time domain data through one-dimensional range image processing. Based on the time domain data, the time domain data corresponding to the antenna direct leakage echo signal and the time domain data corresponding to the clutter signal can be distinguished; the time domain data corresponding to the antenna direct leakage echo signal can be obtained through interception processing; and the first antenna direct leakage echo power data can be obtained through time-frequency transformation.

[0062] Based on the following formula, determine the equivalent radar cross section of the antenna direct leakage echo;

[0063] C A =A-C+σ;

[0064] Among them, C A is the equivalent radar cross section of the antenna direct leakage echo, A is the power data of the first antenna direct leakage echo, C is the power data of the preset calibration body echo, and σ is the equivalent radar cross section of the known calibration body echo.

[0065] Preferably, the calibration module 6 can also be specifically used to: determine the second antenna direct leakage echo power data and the target plasma spectrum expansion effect signal echo power data in the target echo data to be measured, wherein, in the target echo data to be measured, the frequency data at the preset measurement frequency position is the second antenna direct leakage echo power data, and the frequency data at other frequency positions is the target plasma spectrum expansion effect signal echo power data to be measured;

[0066] Based on the following formula, the equivalent radar cross section of the echo of the plasma spectrum expansion effect signal of the target to be measured is determined;

[0067] C F =F-A'+C A ;

[0068] Among them, C F is the equivalent radar cross section of the signal echo of the plasma spectrum expansion effect of the target to be measured, F is the echo power data of the signal echo of the plasma spectrum expansion effect of the target to be measured; A' is the direct leakage echo power data of the second antenna; C A is the equivalent radar cross section of the antenna direct leakage echo.

[0069] The plasma spectrum expansion effect equivalent radar cross section calibration system provided in the present embodiment obtains background echo data including antenna direct leakage echo data and preset calibration body echo data in a wind tunnel by setting a transceiver for antenna direct leakage echo calibration, determines the antenna direct leakage echo equivalent radar cross section according to the background echo data and the preset calibration body echo data by setting a calibration module, obtains echo data of a target to be measured in a wind tunnel under a detonation experimental environment by setting a transceiver for plasma spectrum expansion effect signal echo calibration, determines the equivalent radar cross section of the plasma spectrum expansion effect signal echo of the target to be measured according to the antenna direct leakage echo equivalent radar cross section and the target to be measured echo data by the calibration module, and realizes the equivalence of the plasma spectrum expansion effect signal echo of the target to be measured to the radar cross section.

[0070] In some preferred embodiments, the antenna direct leakage echo calibration transceiver 4 includes a vector network analyzer 41, which is used to generate a first measurement signal and send it through the signal transmission module 3. The vector network analyzer 41 is also used to obtain background echo data and preset calibration body echo data through the signal transmission module 3, and send the background echo data and preset calibration body echo data to the calibration module 6.

[0071] In some preferred embodiments, the transceiver module 5 for plasma spectrum expansion effect signal echo calibration includes a signal source 51 and a spectrum analyzer 52, wherein: the signal source 51 is used to generate a second measurement signal and send it through the signal transmission module 3; the spectrum analyzer 52 is used to obtain the echo data of the target to be measured through the signal transmission module 3, and send the echo data of the target to be measured to the calibration module 6.

[0072] In some preferred embodiments, the high-speed airflow generating device 2 and the spectrometer 52 are configured to synchronously trigger the signal after the signal source 51 sends the second measurement signal, so that when the high-speed airflow generating device 2 fills the wind tunnel 1 with high-speed test gas, the spectrometer 52 starts to acquire the echo data of the target to be measured. The signal source 51 continuously sends the second measurement signal. The high-speed airflow generating device 2 and the spectrometer 52 synchronously trigger the signal, which can ensure that the echo data of the target to be measured is generated in the detonation test environment.

[0073] In some preferred embodiments, the signal transmission module 3 includes a transceiver antenna 31 and a bridge / circulator 32, wherein the bridge / circulator 32 and the transceiver antenna 31 are used to sequentially receive and send measurement signals, and the transceiver antenna 31 and the bridge / circulator 32 are used to sequentially receive and send echo signals, wherein the measurement signal includes a first measurement signal and a second measurement signal, and the echo signal includes background echo data, preset mark body echo data, and target echo data to be measured.

[0074] In some preferred embodiments, the center frequency of the vector network analyzer 41 is set to a preset measurement frequency, the signal bandwidth is set to any bandwidth value in the interval [1GHz, 4GHz], the number of sampling points is set to any integer number of points in the interval [101, 401], and the transmitting port and receiving port of the vector network analyzer 41 are set to the same port.

[0075] In this embodiment, the preset measurement frequency is preferably 3 GHz, that is, the center frequency of the vector network analyzer 41 is set to 3 GHz, and the center frequency of the first measurement signal is also 3 GHz; the signal bandwidth is preferably 2 GHz, and the number of sampling points is preferably 201.

[0076] In some preferred embodiments, the transmission power of the signal source 51 is set to a preset transmission power, and the transmission frequency is set to a preset measurement frequency; the receiving bandwidth of the spectrum analyzer 52 is set to any bandwidth value in the range of [1MHz, 5MHz], and the resolution is set to any resolution value in the range of [1kHz, 5kHz].

[0077] In this embodiment, the preset measurement frequency is preferably 3 GHz, that is, the transmission frequency of the signal source 51 is 3 GHz, and the frequency of the second measurement signal is also 3 GHz; the preset transmission power is preferably 10 dBm. The receiving bandwidth of the spectrum analyzer 52 is preferably 2 MHz, and the resolution is preferably 2 KHz.

[0078] Embodiment 2

[0079] like Figure 2As shown, the plasma spectrum spreading effect equivalent radar cross section calibration method provided in the embodiment of the present invention is preferably performed by the plasma spectrum spreading effect equivalent radar cross section calibration system of embodiment 1, and the method comprises:

[0080] S210, setting a preset standard body in a measurement area in the wind tunnel;

[0081] S220, the antenna direct leakage echo calibration transceiver sends a first measurement signal to the preset standard body through the signal transmission module, and obtains the preset standard body echo data;

[0082] S230, removing the preset standard from the wind tunnel;

[0083] S240, the antenna direct leakage echo calibration transceiver sends the first measurement signal to the wind tunnel through the signal transmission module, and obtains background echo data in the wind tunnel, wherein the background echo data includes antenna direct leakage echo data;

[0084] S250, the antenna direct leakage echo calibration transceiver sends the preset calibration body echo data and the background echo data to a calibration module;

[0085] S260, setting the target to be measured in the measurement area in the wind tunnel, and setting the wind tunnel to a vacuum environment;

[0086] S270, a high-speed airflow generating device emits high-speed test gas to the target to be measured, forming a detonation experimental environment in the wind tunnel; at the same time, a transceiver module for plasma spectrum expansion effect signal echo calibration sends a second measurement signal to the target to be measured in the detonation experimental environment through the signal transmission module, and obtains the echo data of the target to be measured in the detonation experimental environment, and sends the echo data of the target to be measured to the calibration module, wherein the frequency of the second measurement signal is the same as the center frequency of the first measurement signal, and both are preset measurement frequencies;

[0087] S280. The calibration module determines the equivalent radar cross section of the antenna direct leakage echo according to the background echo data and the preset calibration body echo data, and determines the equivalent radar cross section of the plasma spectrum spreading effect signal echo of the target to be measured at the preset measurement frequency according to the equivalent radar cross section of the antenna direct leakage echo and the echo data of the target to be measured.

[0088] The plasma spectrum expansion effect equivalent radar cross section calibration method provided in this embodiment obtains background echo data including antenna direct leakage echo data and preset calibration body echo data in a wind tunnel through a transceiver for antenna direct leakage echo calibration, determines the antenna direct leakage echo equivalent radar cross section according to the background echo data and the preset calibration body echo data through a calibration module, obtains the echo data of the target to be measured in the wind tunnel under a detonation experimental environment through a transceiver for plasma spectrum expansion effect signal echo calibration, determines the equivalent radar cross section of the plasma spectrum expansion effect signal echo of the target to be measured through the calibration module according to the antenna direct leakage echo equivalent radar cross section and the target to be measured echo data, and can achieve the equivalence of the plasma spectrum expansion effect signal echo of the target to be measured to the radar cross section.

[0089] On the basis of the above embodiments, further, the antenna direct leakage echo calibration transceiver device includes a vector network analyzer, the vector network analyzer generates the first measurement signal and sends it through the signal transmission module, the vector network analyzer also obtains the background echo data and the preset calibration body echo data through the signal transmission module, and sends the background echo data and the preset calibration body echo data to the calibration module.

[0090] On the basis of the above embodiments, further, the plasma spectrum spreading effect signal echo calibration transceiver module includes a signal source and a spectrum analyzer, wherein:

[0091] The signal source generates the second measurement signal and sends it through the signal transmission module; the spectrum analyzer obtains the echo data of the target to be measured through the signal transmission module, and sends the echo data of the target to be measured to the calibration module.

[0092] On the basis of the above embodiments, further, after the signal source sends the second measurement signal, the high-speed airflow generating device and the spectrometer synchronize trigger signals so that when the high-speed airflow generating device fills the wind tunnel with high-speed test gas, the spectrometer starts to acquire the echo data of the target to be measured.

[0093] On the basis of the above embodiments, further, the signal transmission module includes a transceiver antenna and a bridge / circulator, the bridge / circulator and the transceiver antenna sequentially receive and send the measurement signal, the transceiver antenna and the bridge / circulator sequentially receive and send the echo signal, wherein the measurement signal includes the first measurement signal and the second measurement signal, and the echo signal includes the background echo data, the preset mark echo data and the target echo data.

[0094] On the basis of the above embodiments, further, the center frequency of the vector network analyzer is a preset measurement frequency, the signal bandwidth is any bandwidth value in the interval [1GHz, 4GHz], the number of sampling points is any integer number of points in the interval [101, 401], and the transmitting port and receiving port of the vector network analyzer are the same port.

[0095] On the basis of the above embodiments, further, the transmission power of the signal source is a preset transmission power, and the transmission frequency is the preset measurement frequency; the receiving bandwidth of the spectrum analyzer is any bandwidth value in the range of [1MHz, 5MHz], and the resolution is any resolution value in the range of [1kHz, 5kHz].

[0096] On the basis of the above embodiments, further, the calibration module performs vector subtraction processing on the preset calibration body echo data and the background echo data to obtain vector subtraction data; performs one-dimensional range image imaging interception and time-frequency transformation processing on the vector subtraction data to obtain preset calibration body echo power data; performs one-dimensional range image imaging interception and time-frequency transformation processing on the background echo data to obtain first antenna direct leakage echo power data; based on the following formula, the equivalent radar scattering cross section of the antenna direct leakage echo is determined;

[0097] C A =A-C+σ;

[0098] Among them, C A is the equivalent radar scattering cross section of the antenna direct leakage echo, A is the power data of the first antenna direct leakage echo, C is the power data of the preset calibration body echo, and σ is the equivalent radar scattering cross section of the known calibration body echo.

[0099] On the basis of the above embodiments, further, the calibration module determines the second antenna direct leakage echo power data and the target plasma spectrum spreading effect signal echo power data in the target echo data, wherein, in the target echo data, the frequency data at the preset measurement frequency position is the second antenna direct leakage echo power data, and the frequency data at other frequency positions is the target plasma spectrum spreading effect signal echo power data; based on the following formula, the equivalent radar scattering cross section of the target plasma spectrum spreading effect signal echo is determined;

[0100] C F =F-A'+C A ;

[0101] Among them, C Fis the equivalent radar scattering cross section of the plasma spectrum expansion effect signal echo of the target to be measured, F is the echo power data of the plasma spectrum expansion effect signal of the target to be measured; A' is the direct leakage echo power data of the second antenna; C A is the equivalent radar cross section of the antenna direct leakage echo.

[0102] The plasma spectrum spreading effect equivalent radar cross section calibration method provided in an embodiment of the present invention can be executed by the plasma spectrum spreading effect equivalent radar cross section calibration system provided in an embodiment of the present invention, and the execution steps and beneficial effects are not repeated here.

[0103] In summary, the plasma spectrum expansion effect equivalent radar cross-section calibration system and method provided by the present invention, by setting a transceiver for antenna direct leakage echo calibration, obtains background echo data including antenna direct leakage echo data and preset calibration body echo data in a wind tunnel, and by setting a calibration module, determines the antenna direct leakage echo equivalent radar cross-section according to the background echo data and the preset calibration body echo data, and by setting a transceiver for plasma spectrum expansion effect signal echo calibration, obtains the echo data of the target to be measured in the wind tunnel under the detonation experimental environment, and by using the calibration module, determines the equivalent radar cross-section of the plasma spectrum expansion effect signal echo of the target to be measured according to the antenna direct leakage echo equivalent radar cross-section and the target to be measured echo data, thereby achieving the equivalence of the plasma spectrum expansion effect signal echo of the target to be measured to the radar cross-section.

[0104] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A plasma spectrum expansion effect equivalent radar cross section calibration system, It is characterized in that It includes a wind tunnel, a high-speed airflow generating device, a signal transmission module, a transceiver for antenna direct leakage echo calibration, a transceiver module for plasma spectrum expansion effect signal echo calibration, and a calibration module, wherein: The high-speed airflow generating device is used to fill the wind tunnel with high-speed test gas; The wind tunnel is used to form a detonation test environment by using the high-speed test gas filled therein; The antenna direct leakage echo calibration transceiver is used to send a first measurement signal into the wind tunnel through the signal transmission module, and obtain background echo data and preset standard echo data in the wind tunnel, and send the background echo data and the preset standard echo data to the calibration module, wherein the background echo data includes antenna direct leakage echo data; The plasma spectrum spreading effect signal echo calibration transceiver module is used to send a second measurement signal to the wind tunnel under the detonation experiment environment through the signal transmission module, and obtain the echo data of the target to be measured in the wind tunnel under the detonation experiment environment, and send the echo data of the target to be measured to the calibration module, wherein the frequency of the second measurement signal is the same as the center frequency of the first measurement signal, and both are preset measurement frequencies; The calibration module is used to determine the equivalent radar cross-section of the antenna direct leakage echo according to the background echo data and the preset calibration body echo data, and to determine the equivalent radar cross-section of the plasma spectrum spreading effect signal echo of the target to be measured at the preset measurement frequency according to the equivalent radar cross-section of the antenna direct leakage echo and the echo data of the target to be measured.

2. The plasma spectrum spreading effect equivalent radar cross section calibration system according to claim 1, It is characterized in that The antenna direct leakage echo calibration transceiver device includes a vector network analyzer, which is used to generate the first measurement signal and send it through the signal transmission module. The vector network analyzer is also used to obtain the background echo data and the preset calibration body echo data through the signal transmission module, and send the background echo data and the preset calibration body echo data to the calibration module.

3. The plasma spectrum spreading effect equivalent radar cross section calibration system according to claim 1 or 2, It is characterized in that The plasma spectrum expansion effect signal echo calibration transceiver module includes a signal source and a spectrum analyzer, wherein: The signal source is used to generate the second measurement signal and send it through the signal transmission module; the spectrum analyzer is used to obtain the echo data of the target to be measured through the signal transmission module, and send the echo data of the target to be measured to the calibration module.

4. The plasma spectrum spreading effect equivalent radar cross section calibration system according to claim 3, It is characterized in that The high-speed airflow generating device and the spectrometer are configured to synchronously trigger a signal after the signal source sends the second measurement signal, so that when the high-speed airflow generating device fills the wind tunnel with high-speed test gas, the spectrometer starts to acquire the echo data of the target to be measured.

5. The plasma spectrum spreading effect equivalent radar cross section calibration system according to claim 1, It is characterized in that The signal transmission module includes a transceiver antenna and a bridge / circulator, wherein the bridge / circulator and the transceiver antenna are used to sequentially receive and send measurement signals, and the transceiver antenna and the bridge / circulator are used to sequentially receive and send echo signals, wherein the measurement signal includes the first measurement signal and the second measurement signal, and the echo signal includes the background echo data, the preset marker echo data, and the target echo data.

6. The plasma spectrum spreading effect equivalent radar cross section calibration system according to claim 2, It is characterized in that The center frequency of the vector network analyzer is set to a preset measurement frequency, the signal bandwidth is set to any bandwidth value in the interval [1GHz, 4GHz], the number of sampling points is set to any integer number of points in the interval [101, 401], and the transmitting port and receiving port of the vector network analyzer are set to the same port.

7. The plasma spectrum spreading effect equivalent radar cross section calibration system according to claim 3, It is characterized in that The transmission power of the signal source is set to the preset transmission power, and the transmission frequency is set to the preset measurement frequency; the receiving bandwidth of the spectrum analyzer is set to any bandwidth value in the range of [1MHz, 5MHz], and the resolution is set to any resolution value in the range of [1kHz, 5kHz].

8. The plasma spectrum spreading effect equivalent radar cross section calibration system according to claim 1, It is characterized in that The calibration module is used for: Performing vector subtraction processing on the preset target echo data and the background echo data to obtain vector subtraction data; Performing one-dimensional range image interception and time-frequency transformation processing on the vector subtraction data to obtain preset marker echo power data; Performing one-dimensional range image interception and time-frequency transformation processing on the background echo data to obtain first antenna direct leakage echo power data; Based on the following formula, the equivalent radar cross section of the antenna direct leakage echo is determined; C A =A-C+σ; Among them, C A is the equivalent radar scattering cross section of the antenna direct leakage echo, A is the power data of the first antenna direct leakage echo, C is the power data of the preset calibration body echo, and σ is the equivalent radar scattering cross section of the known calibration body echo.

9. The plasma spectrum spreading effect equivalent radar cross section calibration system according to claim 1, It is characterized in that The calibration module is also used for: Determine the second antenna direct leakage echo power data and the target plasma spectrum spreading effect signal echo power data in the target echo data, wherein, in the target echo data, the frequency data at the preset measurement frequency position is the second antenna direct leakage echo power data, and the frequency data at other frequency positions is the target plasma spectrum spreading effect signal echo power data; Based on the following formula, the equivalent radar cross section of the echo of the plasma spectrum spreading effect signal of the target to be measured is determined; C F =F-A’+C A ; Among them, C F is the equivalent radar scattering cross section of the plasma spectrum expansion effect signal echo of the target to be measured, F is the echo power data of the plasma spectrum expansion effect signal of the target to be measured; A' is the direct leakage echo power data of the second antenna; C A is the equivalent radar cross section of the antenna direct leakage echo.

10. A method for calibrating equivalent radar cross section of plasma spectrum expansion effect. It is characterized in that The method is performed by the plasma spectrum spreading effect equivalent radar cross section calibration system according to any one of claims 1 to 9, comprising: Setting a preset standard body in the measurement area of ​​the wind tunnel; The antenna direct leakage echo calibration transceiver sends a first measurement signal to the preset standard body through the signal transmission module, and obtains the preset standard body echo data; removing the preset standard from the wind tunnel; The antenna direct leakage echo calibration transceiver sends the first measurement signal to the wind tunnel through the signal transmission module, and obtains background echo data in the wind tunnel, wherein the background echo data includes antenna direct leakage echo data; The antenna direct leakage echo calibration transceiver sends the preset calibration body echo data and the background echo data to the calibration module; The target to be measured is set in the measuring area of ​​the wind tunnel, and the wind tunnel is set to a vacuum environment; The high-speed airflow generating device emits high-speed test gas to the target to be measured, forming a detonation experimental environment in the wind tunnel; at the same time, the plasma spectrum spreading effect signal echo calibration transceiver module sends a second measurement signal to the target to be measured in the detonation experimental environment through the signal transmission module, and obtains the echo data of the target to be measured in the detonation experimental environment, and sends the echo data of the target to be measured to the calibration module, wherein the frequency of the second measurement signal is the same as the center frequency of the first measurement signal, and both are preset measurement frequencies; The calibration module determines the equivalent radar cross section of the antenna direct leakage echo according to the background echo data and the preset calibration body echo data, and determines the equivalent radar cross section of the plasma spectrum spreading effect signal echo of the target to be measured at the preset measurement frequency according to the equivalent radar cross section of the antenna direct leakage echo and the echo data of the target to be measured.

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