Electromagnetic wave measuring device

Abstract

The invention relates to an electromagnetic wave measuring device, which comprises a frequency mixing antenna module used for collecting energetic material electromagnetic wave signals of different frequency bands by adopting a frequency mixing antenna; the multifunctional signal conditioning module is used for synthesizing the energetic material electromagnetic wave signals of different frequency bands into frequency mixing signals and conditioning the frequency mixing signals; the transmission relay module is used for performing gain compensation on the attenuation amount of the conditioned frequency mixing signal in the transmission process; and the high-speed data acquisition module is used for recording the frequency mixing signal after gain compensation. Precise measurement of the electromagnetic waves of the energetic material can be realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electromagnetic wave measurement, in particular to an electromagnetic wave measurement device. BACKGROUND

[0002] The measurement conditions of energetic material electromagnetic wave are relatively complex, and there are many interference factors in the measurement process. Figure 1 As shown in the figure, the measurement of energetic material electromagnetic wave mainly adopts the measurement mode of "antenna-coaxial cable-oscilloscope", and the measurement place is mostly open space, and a few cases are in closed space. The measured explosive mass is 10g at the minimum and 345kg at the maximum, and most of the range is 100g-1kg. Since the mass of the measured explosive is generally small, the damage power is limited, so the distance between the antenna and the measured explosive is generally 2-10m, and the distance between the antenna and the data storage instrument is in the range of 5-20m. Most of the antennas are horn antennas, followed by rod antennas, and there are also dipole antennas and magnetic induction coils. The size of the antenna is between 30-200cm, and it is placed about 1m above the ground. Except for a few 30Ω, the rest are all 50Ω. The minimum receiving frequency of the antenna is only 80kHz, and the maximum is up to 4GHz. Most of the receiving frequencies are in the range of 10MHz-1GHz. The data recording device basically adopts an oscilloscope, and the maximum sampling rate is 2.5GSa / s. The sampling frequency range is 20kHz-1GHz, the data recording time is as short as 0.3μs, and as long as 100ms, and the average recording time is 1ms-10ms. The antenna and the oscilloscope are generally connected by a coaxial cable, the most commonly used model is SYV50-5 series, and RK-1 cable is occasionally used. In most cases, it is directly connected, and there are also signal conditioners for signal amplification. The cable impedance is basically 50Ω.

[0003] The electromagnetic wave measurement system of the above-mentioned prior art is mainly suitable for regular modulated electromagnetic waves, the amplitude of the electromagnetic signal changes little, and there is no need for front-end signal conditioning. Most of them adopt the "antenna-coaxial cable-oscilloscope" structure. The modulation electromagnetic signal has a short cycle, and the average recording time of the data acquisition instrument is in the range of 1ms-10ms. The modulated electromagnetic wave will not produce shock wave or heat flow, and will not cause damage to the measuring instrument. The measurement process does not need to consider factors such as signal transmission attenuation, but the measurement environment of energetic material electromagnetic wave is relatively complex, and the measurement conditions are not easy to control. The signal change amplitude of the energetic material electromagnetic wave is large, and signal high-precision coefficient adjustment device and data acquisition instrument power overload protection device are needed. The existing technology does not have this function. Due to the uneven structure of the radio frequency cable, the voltage standing wave ratio must exist. Part of the energy is reflected through multiple transmissions and finally returns to the transmitting end. Therefore, the effect of improving the structure of the radio frequency cable to reduce the attenuation is very limited, and the energetic material electromagnetic wave signal transmission attenuation is large, and no signal attenuation compensation measures are taken. SUMMARY

[0004] To solve the problems existing in the prior art, the electromagnetic wave measuring device is provided to realize precise measurement of electromagnetic waves of energetic materials.

[0005] To achieve the above-mentioned purpose, the present application provides the following solutions:

[0006] An electromagnetic wave measuring device comprises:

[0007] A mixed frequency antenna module is configured to collect electromagnetic wave signals of energetic materials in different frequency bands by using a mixed frequency antenna.

[0008] A multifunctional signal conditioning module is configured to combine the electromagnetic wave signals of energetic materials in different frequency bands into a mixed frequency signal and to condition the mixed frequency signal.

[0009] A transmission relay module is configured to perform gain compensation on the attenuation of the conditioned mixed frequency signal during transmission.

[0010] A high-speed data acquisition module is configured to record the mixed frequency signal after gain compensation.

[0011] Optionally, the mixed frequency antenna module comprises:

[0012] A mixed frequency antenna sub-module is configured to collect electromagnetic wave signals of energetic materials in different frequency bands by using a mixed frequency antenna.

[0013] A matching circuit sub-module is configured to set a matching circuit for a low-frequency antenna in the mixed frequency antenna and to adjust the receiving capability of the low-frequency antenna.

[0014] Optionally, the mixed frequency antenna comprises a short wave antenna, an ultra-wideband antenna, and a microstrip antenna.

[0015] The microstrip antenna is a microstrip antenna of a target array and is fed by a T-shaped power divider.

[0016] Optionally, the matching circuit sub-module comprises:

[0017] A short wave matching unit is configured to set a first load in the matching circuit of the short wave antenna, accumulate electromagnetic wave energy, adjust the receiving capability of the short wave antenna, and introduce a two-stage radio frequency transformer and an LC matching circuit to condition the port impedance of the short wave antenna to a standard impedance.

[0018] An ultra-wideband matching unit is configured to set a second load in the matching circuit of the ultra-wideband antenna, accumulate electromagnetic wave energy, adjust the receiving capability of the ultra-wideband antenna, and introduce a one-stage radio frequency transformer and an LC matching circuit to condition the port impedance of the ultra-wideband antenna to a standard impedance.

[0019] Optionally, the multifunctional signal conditioning module comprises:

[0020] The combiner submodule is used for setting the package size of the microstrip circuit, and path isolation is performed on the input end; when the input end is excited by an even mode voltage, different paths have the same phase, and signals are transmitted along the stepped impedance transformer; when the input end is excited by an odd mode voltage, different paths have a phase difference reaching a target value, and signals are transmitted along the isolation resistance;

[0021] The regulator submodule is used for setting an amplifier with a target gain and a step attenuator with a target adjustment range, and full-band signal adjustment is performed on the output signal of the combiner submodule by using the amplifier and the step attenuator.

[0022] The amplifier is a double-chip series structure, and is used for adjusting the gain range to a target level.

[0023] Optionally, the multifunctional signal conditioning module further comprises:

[0024] The limiter submodule is used for setting DC blocking capacitors before and after a low-frequency limiting circuit and a high-frequency limiting circuit, blocking DC level conduction, and limiting the sampling signal power of the high-speed data acquisition module.

[0025] The filter submodule is used for constructing a low-frequency filtering circuit and a high-frequency filtering circuit by using Chebyshev filter structures and Chebyshev microstrip parallel coupling structures respectively, and filtering out target band signals.

[0026] The combiner submodule, the regulator submodule, the filter submodule and the filter submodule are sequentially connected.

[0027] Optionally, the transmission relay module comprises:

[0028] The transmission relay submodule is used for setting a low-frequency transmission circuit and a low-frequency transmission circuit as independent transmission lines, and introducing a gain adjustment network to compensate for the gain of the attenuated mixed signal in the transmission process.

[0029] The present application has the following beneficial effects:

[0030] The present application discloses three kinds of measurement frequency band antennas: a short wave antenna (1.5MHz~30MHz), an ultra-wideband antenna (30MHz~1GHz), and a microstrip antenna (5.9~6.0GHz and 8.4~8.5GHz), the measurement efficiency of the antennas is improved by optimizing the antenna structure and the matching circuit design, and it is ensured that the S parameters of various antennas in the working frequency band are lower than-10dB.

[0031] The application adopts a modular design to design a signal conditioner with combiner, amplifier, limiter and filter functions. The combiner module can realize mixed antenna cooperative measurement, and improve the utilization rate of sampling channels. The amplifier module adopts a "fixed gain amplifier + step attenuator" structure, which can not only realize full-band 0~30dB step adjustment, but also can improve the adjustment coefficient accuracy from 3dB to 0.5dB. The limiter module limits the sampling signal power to below 65% of the maximum power of the data acquisition instrument, achieving the purpose of preventing power overload of the data acquisition instrument. The filter module has an out-of-band suppression attenuation of more than 30dB, effectively improving the sampling signal quality. A repeater is designed for attenuation compensation, and the attenuation compensation rate of the repeater to the signal transmission cable is more than 95% after testing. BRIEF DESCRIPTION OF DRAWINGS

[0032] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0033] Figure 1 A schematic diagram of the measurement of electromagnetic waves of the energetic material in the background art of the present application;

[0034] Figure 2 A schematic diagram of the short wave antenna and ultra-wideband antenna design model and structure size of the embodiment of the present application; wherein (a) is a schematic diagram of a short wave antenna model, (b) is a schematic diagram of an ultra-wideband antenna model, (c) is a schematic diagram of the internal structure of an ultra-wideband antenna, and (d) is a schematic diagram of a short wave antenna structure;

[0035] Figure 3 A schematic diagram of the antenna unit model and structure model of the microwave antenna of the embodiment of the present application;

[0036] Figure 4 A schematic diagram of the short wave antenna and ultra-wideband antenna matching circuit design of the embodiment of the present application;

[0037] Figure 5 A schematic diagram of the combiner circuit design of the embodiment of the present application;

[0038] Figure 6 A schematic diagram of the amplifier + attenuation adjustment circuit design of the embodiment of the present application;

[0039] Figure 7 A schematic diagram of the limiter circuit design of the embodiment of the present application;

[0040] Figure 8 A schematic diagram of the filter circuit design of the embodiment of the present application;

[0041] Figure 9 The low frequency and high frequency signals of the transmission relay of the embodiment of the present application are independent transmission line diagrams; wherein (a) is an independent transmission circuit diagram, and (b) is a diagram of the adjusted relay gain compensation index,

[0042] Figure 10 The embodiment of the present application is a kind of electromagnetic wave measuring device schematic diagram. DETAILED DESCRIPTION

[0043] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0044] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the present application will be further described in detail below with reference to the drawings and specific embodiments.

[0045] The embodiment discloses an electromagnetic wave measuring device, comprising: a mixed frequency antenna module for collecting electromagnetic wave signals of energetic materials of different frequency bands by using a mixed frequency antenna; a multifunctional signal conditioning module for synthesizing the electromagnetic wave signals of the energetic materials of different frequency bands into a mixed frequency signal and conditioning the mixed frequency signal; a transmission relay module for gain compensation of the attenuation amount of the conditioned mixed frequency signal in the transmission process; and a high-speed data acquisition module for recording the gain-compensated mixed frequency signal.

[0046] Further, the mixed frequency antenna module comprises: a mixed frequency antenna submodule for collecting electromagnetic wave signals of energetic materials of different frequency bands by using a mixed frequency antenna; and a matching circuit submodule for setting a matching circuit for a low frequency band antenna in the mixed frequency antenna and adjusting the receiving capacity of the low frequency band antenna.

[0047] Specifically, to maximize the collection of electromagnetic wave signals of energetic materials, the present application expands the antenna design frequency band to 0.01MHz-1GHz, 5.9-6.0GHz and 8.4-8.5GHz. The propagation process of electromagnetic waves of energetic materials from the center to the periphery is not uniform, and the propagation direction is not specific and concentrated, so it is necessary to align the beam direction of the antenna with the radiation source. A short wave omnidirectional antenna is used to measure electromagnetic waves of 1.5-30MHz frequency band, and an ultra-wideband antenna with a double-cone structure inside is used to measure electromagnetic waves of 30MHz-1GHz frequency band. The design model and structure size of the short wave antenna and the ultra-wideband antenna are as follows: Figure 2(a)-(d) shown. The microwave antenna is measured in the 5.9~6.0GHz and 8.4~8.5GHz frequency bands, and the feed mode of the microwave patch antenna is generally direct contact type feed, which can be divided into side feed and back feed (bottom feed). The present application adopts a side feed direct contact type feed antenna design, and the antenna impedance is matched through a concave feed structure. The antenna unit model and structure model are shown in Figure 3 In order to improve the antenna gain, the microwave antenna adopts a 1*2 array design, uses a T-type power divider for feeding, and the antenna substrate is Rogers4003C with a thickness of 1.524mm and a dielectric constant of 3.55. Through the data comparison and analysis of the inventors, the best size of the two frequency band microwave antennas is obtained: Figure 3

[0048] 5.9~6.0GHz frequency band:

[0049] Lpa=12.4mm, Off=2.0mm, Wpa=20mm, L1=6.13mm, L2=18.26mm, Lpcb=60mm, Op=30mm, Wpcb=45mm;

[0050] 8.4~8.5GHz frequency band:

[0051] Lpa=8.65mm, Off=2.25mm, Wpa=13mm, L1=4mm, L2=9.6mm, Lpcb=41.4mm, Op=20mm, Wpcb=24.1mm.

[0052] Further, the matching circuit sub-module includes: a short wave matching unit, configured to set a first load in the matching circuit of the short wave antenna, accumulate electromagnetic wave energy, adjust the receiving capability of the short wave antenna, and introduce a two-stage radio frequency transformer and an LC matching circuit to regulate the port impedance of the short wave antenna to a standard impedance; and an ultra-wideband matching unit, configured to set a second load in the matching circuit of the ultra-wideband antenna, accumulate electromagnetic wave energy, adjust the receiving capability of the ultra-wideband antenna, and introduce a one-stage radio frequency transformer and an LC matching circuit to regulate the port impedance of the ultra-wideband antenna to a standard impedance.

[0053] Specifically, in order to improve the receiving performance of the low frequency band antenna, the present application designs a matching circuit for the low frequency band antenna. The short wave antenna and the ultra-wideband antenna matching circuit design are shown in Figure 4 ​As shown. The impedance of the Term2 port of the shortwave antenna matching circuit is Z = (1.7 - j * 1348.1) Ω. Because the shortwave antenna measurement frequency band (1.5~30MHz) is too low, the resistance (real part 1.7) of the port impedance is too low, and the capacitive reactance (imaginary part 1348) is too high. Therefore, a load R3 = 10kΩ is designed near the Term2 port of the matching circuit to accumulate electromagnetic wave energy and enhance the antenna's receiving capability. Simultaneously, in the shortwave antenna matching circuit (… Figure 4 The design of a two-stage RF transformer (XFM1 and XFM2) + LC matching circuit is used to condition the port impedance to the standard impedance of 50Ω. The design concept of the ultra-wideband antenna matching circuit is the same as that of the shortwave antenna, but the ultra-wideband antenna has a higher measurement frequency band (30MHz~1GHz). In the Term2 port impedance Z=(14.73-j*39.47)Ω, the resistance and capacitive reactance values ​​are relatively small compared to the antenna impedance difference. Therefore, in the ultra-wideband antenna matching circuit ( Figure 4 (Below) Only one radio frequency transformer was designed.

[0054] Furthermore, the multi-functional signal conditioning module includes: a combiner submodule, used to set the package size of the microstrip line circuit and isolate the input path. When the input is excited by an even-mode voltage, the different paths are in phase, and the signal is transmitted along the stepped impedance transformer. When the input is excited by an odd-mode voltage, the different paths are out of phase to the target value, and the signal is transmitted along the isolation resistor; and a regulator submodule, used to set the amplifier with the target gain and the step attenuator with the target adjustment range. The amplifier and the step attenuator are used to adjust the output signal of the combiner submodule across the entire frequency band. The amplifier is a dual-chip series structure used to adjust the gain range to the target level.

[0055] Furthermore, the multi-functional signal conditioning module also includes: a limiter submodule, used to set DC blocking capacitors before and after the low-frequency and high-frequency limiting circuits to prevent DC level conduction and limit the sampling signal power of the high-speed data acquisition module; and a filter submodule, used to construct low-frequency and high-frequency filter circuits using Chebyshev filter structures and Chebyshev microstrip parallel coupling structures respectively to filter out signals in the target frequency band; wherein, the combiner submodule, regulator submodule, filter submodule, and filter submodule are connected in sequence.

[0056] Specifically, the multi-functional signal conditioner is designed as follows: the signal conditioner adopts a modular design approach, consisting of a combiner module, an amplifier + attenuator regulator module, a limiter module, and a filter module.

[0057] The function of the combiner module is to synthesize electromagnetic wave signals from energetic materials at different frequency bands into a mixed signal, reducing the occupation of acquisition channels. The circuit design of the combiner module, such as... Figure 5As shown, the circuit adopts a microstrip line circuit with a typical Wilkinson architecture. Since the high-frequency signal frequency is above 5 GHz, the package size can be limited to 0.5λ=0.5c / f=1.5×108 / 5×109=3 cm, while the advantages of wide bandwidth and low cost are also possessed. The matching impedance of each port of the circuit is 50Ω. In order to avoid mutual interference of signals, an isolation resistor method is added to isolate the input paths of the combiner module. When the input end is excited by an even-mode voltage, the two paths have the same phase, and the signal is transmitted along the ladder impedance transformer. At this time, the isolation resistor has no signal, and the combiner circuit is completely matched. When the input end is excited by an odd-mode voltage, the two paths have a phase difference of 180°, and the signal is transmitted along the isolation resistor. Since the combiner module is designed with a number m=1, and the 1 / 4 wavelength impedance is 100Ω, R / / 100Ω=50Ω, and the isolation resistor R=100Ω.

[0058] The amplifier + attenuation adjustment module circuit design is as shown in Figure 6 A fixed gain amplifier with a gain of 30 dB is designed, and a step attenuator with an adjustment range of 0~30 dB is added. The structure of "fixed gain amplifier + step attenuator" is used to realize full-band signal adjustment. The main chip HMC460LC5 of the amplifier circuit has an effective frequency band of 1 MHz~10 GHz, a supply voltage of +8V, a power saturation point of +16.5dBm, a noise coefficient of 2.5dB, and a maximum gain of 15dB. In order to increase the adjustment range of the signal conditioner, two HMC460LC5 chips are connected in series in the amplifier module circuit, which can increase the gain range to 30dB. The main chip HMC424ALH5 of the attenuator circuit has an effective frequency band of DC~13GHz, an attenuation range of 0~31.5dB, an adjustment accuracy of 0.5dB, and a typical bit error rate of ±0.3dB. The attenuation range of the attenuator is 0~31.5dB, and the adjustment accuracy of the step attenuator can reach 0.5dB. The structure of "fixed gain amplifier + step attenuator" can make the adjustment coefficient of the signal conditioner more accurate.

[0059] The limiter module circuit design is as shown in Figure 7The low-frequency circuit adopts RLM-33-2W+ as a main chip, and the high-frequency circuit adopts CLM-83-2W+ as a main chip, and the input power range of the chip can reach 12dBm~32dBm. Since the limiter will be affected by the direct current voltage, a 100nF direct current capacitor is designed before and after the main chip to prevent the direct current level from being turned on. The maximum range of the data acquisition instrument of the measurement system is ±2.50V, and the impedance of the known electromagnetic wave measurement system is 50Ω, so the power P=U2 / R=2.52 / 50=125mW, and the corresponding signal power is 20.97dBm. Therefore, the maximum signal power that the data acquisition instrument can withstand is 20.97dBm. The maximum output power of the limiter module is 11.5~13dBm, which accounts for 55~62% of the maximum power that the data acquisition instrument can withstand. Therefore, the sampling signal power (12dBm~32dBm) can be limited to below 65% by using the limiter module, so as to achieve the purpose of preventing the data acquisition instrument from being overloaded.

[0060] Filter module design: the application adopts a mixed antenna combining measurement method, which requires that the in-band signal has frequency selection characteristics. If the electromagnetic wave frequency band of the containing energy material is highly overlapped with the working frequency band of the measurement instrument, due to the distribution parameters of the radio frequency channel, out-of-band coupling interference will be generated. Therefore, it is necessary to increase the filter module, and the circuit design is as shown in Figure 8 The low-frequency circuit adopts a low-pass filter circuit with LC Chebyshev filter structure, and the main function is to filter out signals above 1GHz. The attenuation rate reaches 40dB at the cutoff frequency of 2GHz. The high-frequency circuit adopts a band-pass filter circuit with Chebyshev microstrip parallel coupling structure, and the main function is to filter out signals below 5.9GHz and above 8.5GHz. The attenuation rate reaches 30dB at the cutoff frequencies of 5GHz and 10GHz.

[0061] Further, the transmission relay module comprises a transmission relay submodule, which is used for setting the low-frequency transmission circuit and the low-frequency transmission circuit as independent transmission lines and introducing a gain adjustment network to compensate the gain of the conditioned mixed signal in the transmission process.

[0062] Specifically, the transmission relay: the low-frequency and high-frequency signals of the transmission relay are independent transmission lines, and the circuit is as shown in Figure 9 (a). The circuit adopts HMC460LC5 as a main amplification chip. Since the attenuation of the radio frequency cable to the high-frequency signal is low, the high-frequency circuit of the relay uses a two-stage amplification chip. The attenuation of the signal transmission cable changes with the frequency, and the correlation degree of the gain compensation trend of the relay and the attenuation trend of the radio frequency cable should tend to be consistent. The gain compensation index of the relay is as shown in Figure 9(b) shown: 100MHz~1GHz frequency band gain compensation range 2.21~8.88dB, 5.9~8.5GHz frequency band gain compensation range 24.71~28.68dB, the compensation rate of the repeater to the signal transmission cable hundred-meter attenuation exceeds 95%.

[0063] As Figure 10 shown, the embodiment discloses an electromagnetic wave measuring device, which comprises: a short wave antenna, an ultra-wideband antenna, a microstrip antenna combining measurement method, covering the frequency range of 1.5MHz~1GHz, 5.9~6.0GHz, 8.4~8.5GHz, the radio frequency link front end includes an antenna and a signal conditioner, which is connected with a data acquisition instrument through a signal transmission line, and a high-speed data acquisition card is used to record signals.

[0064] The high-speed data acquisition card based on FPGA and the PXIe communication interface can provide high-quality signal acquisition function and trigger reliability. In the preliminary debugging stage of the measurement system, the FIFO mode is used for data transmission, and the data is stored to the computer hard disk to obtain the data storage length for a long time. However, each high-speed data acquisition card contains 4 sampling channels, and the data transmission amount of each sampling channel with a data acquisition channel of up to 20GSa / s per second exceeds 80GB (1GS=1024MSample). Such data transmission amount has far exceeded the upper limit of the transmission rate of the bus interface. In actual application, the data can only be written into the on-board storage area, and the time length of simultaneous sampling of 4 data channels is limited within 813ms, the time domain signal of the data acquisition card is accurate to 10-9s, the sampling time length is set to 810ms, wherein the sampling time length before triggering is set to 10ms, and the sampling time length after triggering is set to 800ms.

[0065] The above-described embodiments are only descriptions of the preferred modes of the present application, and do not limit the scope of the present application. Without departing from the design spirit of the present application, various modifications and improvements of the technical solutions of the present application made by those skilled in the art shall fall within the protection scope determined by the claims of the present application.

Claims

1. An electromagnetic wave measuring device, characterized in that, include: A frequency-mixing antenna module is used to collect electromagnetic wave signals from energetic materials at different frequency bands using a frequency-mixing antenna. A multi-functional signal conditioning module is used to synthesize electromagnetic wave signals of energetic materials in different frequency bands into a mixed signal and to condition the mixed signal. The transmission relay module is used to compensate for the attenuation of the conditioned mixed signal during transmission. The high-speed data acquisition module is used to record the gain-compensated mixed signal.

2. The electromagnetic wave measuring device according to claim 1, characterized in that, The mixer antenna module includes: The mixing antenna submodule is used to collect electromagnetic wave signals of energetic materials in different frequency bands using a mixing antenna; The matching circuit submodule is used to set up a matching circuit for the low-frequency band antenna in the mixer antenna and adjust the receiving capability of the low-frequency band antenna.

3. The electromagnetic wave measuring device according to claim 1, characterized in that, The mixing antenna includes: a shortwave antenna, an ultra-wideband antenna, and a microstrip antenna; The microstrip antenna is a microstrip antenna for the target array and is fed by a T-type power divider.

4. The electromagnetic wave measuring device according to claim 3, characterized in that, The matching circuit submodule includes: The shortwave matching unit is used to set a first load in the matching circuit of the shortwave antenna, accumulate electromagnetic wave energy, adjust the receiving capability of the shortwave antenna, and introduce two-stage radio frequency transformers and LC matching circuits to condition the port impedance of the shortwave antenna to the standard impedance. An ultra-wideband matching unit is used to set a second load in the matching circuit of the ultra-wideband antenna, accumulate electromagnetic wave energy, adjust the receiving capability of the ultra-wideband antenna, and introduce a first-stage radio frequency transformer and LC matching circuit to condition the port impedance of the ultra-wideband antenna to the standard impedance.

5. The electromagnetic wave measuring device according to claim 1, characterized in that, The multi-functional signal conditioning module includes: The combiner submodule is used to set the package size of the microstrip line circuit and to isolate the input path. When the input is excited by an even-mode voltage, the different paths are in phase and the signal is transmitted along the stepped impedance transformer. When the input is excited by an odd-mode voltage, the different paths are out of phase to the target value and the signal is transmitted along the isolation resistor. The regulator submodule is used to set the amplifier with target gain and the step attenuator with target adjustment range, and to use the amplifier and the step attenuator to adjust the output signal of the combiner submodule across the entire frequency band. The amplifier is a dual-chip series structure used to adjust the gain range to the target level.

6. The electromagnetic wave measuring device according to claim 5, characterized in that, The multi-functional signal conditioning module also includes: The limiter submodule is used to set DC blocking capacitors before and after the low-frequency limiter circuit and the high-frequency limiter circuit to prevent DC level conduction and limit the sampling signal power of the high-speed data acquisition module; The filter submodule is used to construct low-frequency filter circuits and high-frequency filter circuits using Chebyshev filter structures and Chebyshev microstrip parallel coupling structures, respectively, to filter out signals in the target frequency band. The combiner submodule, the regulator submodule, the filter submodule, and the filter submodule are connected in sequence.

7. The electromagnetic wave measuring device according to claim 1, characterized in that, The transmission relay module includes: The transmission repeater submodule is used to set the low-frequency transmission circuit and the low-frequency transmission circuit as independent transmission lines, and introduces a gain adjustment network to compensate for the attenuation of the conditioned mixed signal during transmission.

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