Complex electromagnetic environment electromagnetic compatibility field measurement system

Abstract

The invention discloses a complex electromagnetic environment electromagnetic compatibility field measurement system, which belongs to the technical field of electromagnetic testing and comprises an antenna array, a low-noise amplifier module, a receiver and an upper computer. The receiver comprises a radio frequency transceiver and a programmable system-on-chip, and the upper computer is constructed based on a Simulink platform. The system adopts a collaborative architecture of front-end analog signal processing, system-on-chip real-time preprocessing and an upper computer software definition algorithm, converts a GB / s-level high-speed I / Q data stream output by a radio frequency transceiver into a low-speed characteristic data stream through the parallel processing capability of an FPGA (Field Programmable Gate Array), and breaks through the bus bandwidth and upper computer processing bottlenecks; a four-unit antenna linear array and a MUSIC spectrum peak search algorithm are combined, on the premise that high real-time performance is guaranteed, efficient and reliable direction finding and positioning of a point source to be measured in an open complex environment are achieved, a highly-integrated and reconfigurable software and hardware integrated solution is provided, high-precision positioning can be achieved based on the electromagnetic compatibility field measurement system, and the electromagnetic compatibility field measurement system is high in practicability. And thus, support is provided for high-reliability positioning of the electronic device.

Description

Technical Field

[0001] This application belongs to the field of electromagnetic testing technology, and in particular relates to an electromagnetic compatibility field measurement system for complex electromagnetic environments. Background Technology

[0002] As modern industrial equipment develops towards larger scale, integration, and higher power, electromagnetic compatibility (EMC) issues have become a core bottleneck restricting technological breakthroughs in key fields such as aviation, shipbuilding, and rail transportation. Existing electromagnetic interference source localization technologies are mainly based on circuit-level and equipment-level testing in laboratory environments, using methods such as near-field probe scanning and spectrum analysis to identify interference sources. However, these methods face significant limitations in complex industrial scenarios: First, laboratories, limited by space and testing conditions, cannot simulate the real electromagnetic environment of large equipment such as ships and high-speed trains, leading to deviations between interference propagation paths and actual operating conditions. Second, the dense wiring and multi-source interference coupling in industrial settings make it difficult for traditional frequency-scanning localization methods to distinguish between co-channel interference and multi-path superposition effects, significantly reducing localization accuracy. Furthermore, existing standards and testing equipment have long been dominated by Europe and the United States. For example, while SARA's CASSPER virtual anechoic chamber system supports on-site measurements, its technological embargo leads to high costs and supply chain risks for domestic enterprises.

[0003] my country has established a relatively complete technical system in the field of electromagnetic compatibility (EMC) laboratory testing, achieving a series of fruitful research results in areas such as EMC localization and coupling path analysis. However, research on field measurements is still in its early stages, with few academic monographs and papers, and a lack of relevant standards and corresponding testing technologies. Locating EMC sources in industrial settings remains challenging. Firstly, there is currently no standard indoor testing facility capable of accommodating such large test objects. Secondly, comprehensive EMC testing and analysis of equipment requires high-power radiation sources operating at full capacity, making laboratory testing unsuitable. Therefore, developing high-precision EMC source localization technology with independent intellectual property rights and adaptability to complex industrial scenarios has become an urgent need to overcome technological barriers and ensure national industrial security. Summary of the Invention

[0004] This application aims to solve the technical problem of electromagnetic interference positioning. To this end, this application provides an electromagnetic compatibility field measurement system for complex electromagnetic environments. This system can efficiently and reliably perform direction finding and positioning of signals in open and complex environments, more closely resembling the actual working environment of the test object. The test results can better reflect the actual situation. This electromagnetic compatibility field measurement system can achieve high-precision positioning, thereby providing support for the high-reliability positioning of electronic devices.

[0005] This application provides an electromagnetic compatibility field measurement system for complex electromagnetic environments, comprising: Antenna array, used to receive time-domain data streams from the point source under test; The low-noise amplifier module is electrically connected to the antenna array and is used to amplify the time-domain data stream received by the antenna array. The receiver includes an RF transceiver and a programmable system-on-a-chip. The RF transceiver is electrically connected to a low-noise amplifier module. The RF transceiver is used to filter, down-convert, and sample the signal from the low-noise amplifier to convert it into a digital signal. The programmable system-on-a-chip is used to receive the data stream output by the RF transceiver and perform preprocessing to reduce the data transmission rate. The host computer, electrically connected to the programmable on-chip system, is used to receive the preprocessed feature data stream and perform azimuth estimation and positioning of the source to be measured.

[0006] In some implementations, the antenna array includes multiple antenna elements for transmitting the received electromagnetic signals to the programmable on-chip system via a low-noise amplifier module and a radio frequency transceiver.

[0007] In some implementations, the programmable system-on-chip includes an FPGA for parallel preprocessing of data streams.

[0008] In some implementations, the FPGA includes programmable logic (PL), a processing system (PS), and a configuration module; the configuration module is used to initialize the radio frequency transceiver to initialize the logic units of the programmable logic (PL).

[0009] In some implementations, the FPGA also includes a serial port module for processing instruction interaction between the system PS and the host computer.

[0010] In some implementations, the FPGA also includes a digital signal preprocessing module for transmitting and receiving digital signals with the programmable logic unit (PL) and the radio frequency transceiver.

[0011] In some implementations, the FPGA also includes a PL-PS communication module for sending data blocks processed by the programmable logic PL to a designated buffer of the processing system PS.

[0012] In some implementations, the FPGA also includes an Ethernet module for sending the feature data stream preprocessed by the processing system PS to a host computer.

[0013] In some implementations, the host computer has the following built-in features: The buffer module is used to shape the feature data stream; Automatic gain control (AGC) module is used to dynamically adjust the gain of the shaped signal; The autocorrelation function calculation module is used to calculate the autocorrelation matrix and eigenvalue decomposition of the effective feature data within the buffer module, and determine the corresponding noise subspace based on the magnitude of the eigenvalues.

[0014] The peak search module is used to determine the azimuth angle of the incoming wave from the source under test by using the peak search algorithm on the signal output by the automatic gain control (AGC) module.

[0015] In some implementations, the peak search algorithm is as follows: based on the signal output by the automatic gain control (AGC) module, a manifold matrix is ​​constructed and multiplied with the noise subspace to obtain the MUSIC spectral function, and the most prominent peak in the spectrum is found to determine the azimuth angle of the incoming wave.

[0016] As can be seen from the above technical solution, the beneficial effects of this application are as follows: This application ensures the sensitivity and integrity of signal acquisition through an antenna array and a low-noise amplifier module. The antenna array receives multiple time-domain data streams, which are amplified by the low-noise amplifier to provide a high signal-to-noise ratio input signal for subsequent processing, thus laying the foundation for reliable direction finding. The RF transceiver filters, down-converts, and samples the signal, converting the analog signal into a digital signal, eliminating environmental interference and improving signal quality. A programmable on-chip system (SoC) serves as the core processing unit, directly responsible for preprocessing the high-speed data stream output by the RF transceiver to reduce the data transmission rate. The SoC processes four antenna data streams simultaneously and achieves continuous operation through pipeline. This architecture avoids instruction queuing and memory access latency of traditional serial processors (such as CPUs), ensuring high real-time performance of the data processing flow from input to output. The host computer performs azimuth estimation and positioning based on the preprocessed feature data stream. The optimized data stream reduces computational complexity, enabling efficient positioning analysis even in complex environments. This application enables efficient and reliable direction finding and positioning of signals in open and complex environments, more closely resembling the actual working environment of the test object. The test results better reflect the actual situation, improving the reliability of the measurement. This electromagnetic compatibility field measurement system can be applied to intelligent sensors, intelligent sensing systems, and positioning under electromagnetic interference conditions such as satellite positioning. This enables high-precision positioning, thereby providing support for the high-reliability positioning of electronic devices. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced one by one below. Obviously, the accompanying drawings described below are some embodiments of this application. For those skilled in the art, other embodiments and drawings can be obtained based on these drawings without creative effort. Various schematic diagrams according to the embodiments of this application are shown in the accompanying drawings. These drawings are not necessarily drawn to scale. For the purpose of clarity, some details have been enlarged and some details may have been omitted.

[0018] Figure 1 A schematic diagram of an embodiment of the electromagnetic compatibility field measurement system for complex electromagnetic environments of the present invention is shown; Figure 2 A schematic diagram of an embodiment of the antenna array of the present invention is shown; where d represents the element spacing, N represents the number of elements, and θ represents the incident angle; Figure 3 A schematic diagram illustrating the working principle of an embodiment of the receiver of the present invention is shown; Figure 4 A schematic flowchart of an embodiment of the host computer of the present invention is shown. Detailed Implementation

[0019] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. The detailed description of the embodiments of this application provided in the drawings is not intended to limit the scope of the claimed application. The described embodiments are only a part of the embodiments of this application, not all of them. Based on the embodiments in this application, they can be arranged and designed in various different configurations. All other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0020] This application is described below with reference to the accompanying drawings and specific embodiments: Please refer to Figure 1 This application provides an electromagnetic compatibility field measurement system for complex electromagnetic environments, comprising: an antenna array, a low-noise amplifier module (LNA), a receiver, and a host computer. The antenna array is used to receive the time-domain data stream of the source under test. The LNA module is electrically connected to the antenna array and is used to amplify the time-domain data stream received by the antenna array. The receiver includes a radio frequency transceiver (such as AD9363) and a programmable system-on-a-chip (such as Zynq7020). The radio frequency transceiver is electrically connected to the LNA module. The radio frequency transceiver is used to filter, down-convert, and sample the signal from the LNA to convert it into a digital signal. The programmable system-on-a-chip is used to receive the data stream output by the radio frequency transceiver and perform preprocessing to reduce the data transmission rate. The host computer is electrically connected to the programmable system-on-a-chip and is used to receive the preprocessed feature data stream and perform azimuth angle estimation and positioning of the source under test. By adopting a collaborative processing architecture of "analog signal processing by a front-end low-noise amplifier module, real-time preprocessing by a programmable on-chip system, and positioning by a host computer based on feature data streams", efficient and reliable electromagnetic compatibility field measurement is achieved in complex environments. Based on this electromagnetic compatibility test, high-precision positioning can be achieved, thereby providing support for the high-reliability positioning of electronic devices.

[0021] In some implementations, the antenna array employs a four-element linear array layout (e.g.) Figure 2As shown, multiple antenna elements synchronously receive electromagnetic signals and simultaneously transmit the received time-domain data stream to the low-noise amplifier module, providing a foundation for subsequent multi-channel signal processing. Combined with a flexible peak search algorithm based on the Simulink host computer, the time-domain data received by the four antennas is preprocessed in the receiver and then transmitted to the Simulink host computer via Ethernet to utilize the peak search algorithm (music algorithm).

[0022] In some implementations, the low-noise amplifier module (LNA) operates in the frequency range of 325MHz to 3.8GHz and is electrically connected between the antenna array and the radio frequency transceiver. It is used to amplify the weak electromagnetic signals received by the antenna array to ensure the signal-to-noise ratio during signal transmission.

[0023] In some implementations, the receiver includes an AD9363 radio frequency transceiver and a Zynq7020 programmable system-on-a-chip (SAP) Figure 3 As shown, the RF transceiver AD9363 is electrically connected to the low-noise amplifier module, which is used to filter, down-convert and sample the amplified analog signal, convert it into a digital signal and output it to the Zynq7020 programmable on-chip system for preprocessing.

[0024] In some implementations, the Zynq7020 programmable system-on-a-chip integrates an FPGA. The FPGA, with its parallel processing, pipelined architecture, and deterministic latency, can perform real-time preprocessing of the high-speed I / Q data stream (GB / s level) output from the AD9363 RF transceiver, converting it into MB / s or even KB / s level spectral frames or other characteristic data streams, effectively overcoming the bottlenecks of bus bandwidth and host computer processing capabilities. Because the I / Q data rate output by the AD9363 is extremely high (up to tens of MSPS), directly transmitting the raw data stream to the host computer would be limited by bus bandwidth and host computer processing capabilities.

[0025] The aforementioned FPGA processing exhibits high real-time performance because the FPGA can execute multiple operations simultaneously, such as processing data streams from four antennas concurrently, and uses pipeline technology to process data continuously, much like on a production line. This architecture avoids the queuing congestion and unpredictable waiting times that can occur with traditional serial processors (such as CPUs) when processing high-throughput data, thus ensuring that the entire processing flow from data input to result output is real-time in terms of timing. Without the real-time preprocessing of the FPGA, no bus (such as PCIe) or host computer CPU could directly process such a high-speed raw data stream, and the system would not function. While ensuring high real-time performance, efficient and reliable direction finding and positioning of signals are achieved in open and complex environments, providing a highly integrated, reconfigurable, and practical hardware and software integrated solution for electromagnetic compatibility field measurements.

[0026] In some implementations, the FPGA includes programmable logic (PL), a processing system (PS), a configuration module, a serial port module, a digital signal preprocessing module, a PL-PS communication module, and an Ethernet module. The configuration module initializes the AD9363 RF transceiver via an SPI interface, specifically initializing the logic units of the PL. The serial port module handles instruction exchange between the PS and the host computer. The digital signal preprocessing module transmits and receives digital signals with the AD9363 via an LVDS interface. The PL-PS communication module, based on the AXI high-performance bus protocol, acts as a data and control bridge between the PL and PS through a direct memory access (DMA) controller, directly transferring data blocks processed by the PL to a designated buffer in the PS's DDR memory without CPU intervention, ensuring low latency and high determinism in data transmission. The Ethernet module stably transmits the preprocessed feature data stream from the PS to the host computer. The above process is entirely controlled by hardware logic, ensuring the efficiency and real-time performance of data transmission. The ARM processor on the PS side of the processing system is responsible for running the embedded Linux operating system, managing DMA transmission, and sending the characteristic data stream in memory to the host computer stably and orderly via the Ethernet port.

[0027] In some implementations, the host computer is built on the Simulink Software-Defined Radio (SDR) platform and includes built-in buffer modules, automatic gain control (AGC) modules, autocorrelation function calculation modules, and spectral peak search modules, such as... Figure 4 The buffer module reshapes the 1*8 dimensional int16 type little-byte data received from Ethernet into 1024*8 dimensional data; the automatic gain control (AGC) module dynamically adjusts the gain of the reshaped signal to ensure the stability of the multi-channel signal amplitude; the autocorrelation function calculation module calculates the autocorrelation matrix of the effective feature data in the buffer and performs eigenvalue decomposition, determining the corresponding noise subspace based on the eigenvalue magnitude; the peak search module, based on the MUSIC algorithm, constructs a manifold matrix and multiplies it with the noise subspace to obtain the MUSIC spectrum function, determining the azimuth angle of the incoming wave source by finding the most prominent peak in the spectrum. The core direction-finding and positioning algorithm based on peak search is efficiently implemented using the graphical modeling and simulation environment of Simulink on the host computer. In some implementations, the test environment of this system is an open area with a radius of about 15 meters centered on the receiving antenna array (corresponding to 15 times the wavelength of the lowest operating frequency of 325MHz). This area is free of large buildings, metal structures or other strong reflectors, and the signal source under test and the receiving array meet the conditions for unobstructed line-of-sight transmission. Before the experiment, the background spectrum of the target operating frequency band of 325MHz–3.8GHz is scanned by the antenna array to ensure that there are no stable discrete spectral peaks in this frequency band with power more than 10dB higher than the system noise floor or within 20dB of the power of the signal under test, so as to avoid interference sources in the same frequency band from affecting the measurement accuracy.

[0028] In some implementations, the system's workflow is as follows: 1) The four elements of the antenna array synchronously receive the time-domain electromagnetic signals from the source under test; 2) The low-noise amplifier module amplifies the received signals; 3) The RF transceiver AD9363 filters, down-converts, and samples the amplified signals, converting them into digital signals; 4) The FPGA of the Zynq7020 programmable on-chip system performs real-time parallel preprocessing on the digital signals, converting them into feature data streams; 5) The feature data streams are transmitted to the host computer via the Ethernet module; 6) The host computer sequentially completes signal processing through the buffer module, the automatic gain control (AGC) module, and the autocorrelation function calculation module, and then the peak search module executes the MUSIC algorithm to finally achieve azimuth estimation and positioning of the source under test.

[0029] In some optional extended embodiments, the number of antenna array elements can be adjusted according to the measurement accuracy requirements, such as using a six-element or eight-element linear array. The core is to ensure the synchronous reception and transmission of multi-channel signals. The RF transceiver can be replaced with other models with equivalent performance, as long as it can achieve filtering, down-conversion and sampling functions. In addition to the MUSIC algorithm, other super-resolution direction finding algorithms such as ESPRIT can also be used for peak search, all of which can realize the azimuth angle estimation function of the point source under test.

[0030] Regarding the specific implementation methods of this application, it should be noted that: In the description of this application, unless otherwise expressly specified and limited, the terms "connection," "fixed," "connected," etc., should be interpreted broadly. For example, "fixed" can refer to a fixed connection, a detachable connection, or an integral molding; "connection" can refer to a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can refer to the internal connection of two components or the interaction between two components, unless otherwise expressly limited; "connected" can refer to the internal connection of two parts and the connection between two parts, or the spatial connection between them, whereby the two parts are directly or indirectly connected through the part forming the space. The terms "set," "installed," "equipped with," "configured," etc., should also be interpreted broadly. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0031] In the description of this application, the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the system or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application. All directional indications are only used to explain the relative positional relationship and movement between components in a specific orientation. If the specific orientation changes, the directional indication will also change accordingly.

[0032] In the description of this application, the use of terms such as "some embodiments," "optional embodiments," "example," "specific example," "optional example," or "optional embodiment," etc., indicates that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application, but does not imply that these embodiments illustrate and describe all possible forms of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Furthermore, those skilled in the art can combine and integrate the different embodiments or examples described in this specification.

[0033] The present invention has been described in detail above with reference to specific embodiments and exemplary examples. The above description is exemplary and not exhaustive, and is not limited to the disclosed embodiments; the above description should not be construed as a limitation of the present invention. Technical solutions between various embodiments can be combined with each other, but must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed in this application. Although embodiments of the present application have been shown and described, various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present application. Those skilled in the art will understand that various other specific changes and combinations of embodiments based on the technical teachings disclosed in this application, without departing from the essence of the present application, are still within the scope of protection defined by the claims of the present invention and their equivalent technical solutions.

Claims

1. A field measurement system for electromagnetic compatibility in complex electromagnetic environments, characterized in that, include: Antenna array, used to receive time-domain data streams from the point source under test; A low-noise amplifier module, electrically connected to the antenna array, is used to amplify the time-domain data stream received by the antenna array; The receiver includes an RF transceiver and a programmable system-on-a-chip (SoC). The RF transceiver is electrically connected to the low-noise amplifier module. The RF transceiver is used to filter, down-convert, and sample the signal from the low-noise amplifier to convert it into a digital signal. The programmable SoC is used to receive the data stream output by the RF transceiver and perform preprocessing to reduce the data transmission rate. The host computer is electrically connected to the programmable on-chip system and is used to receive the preprocessed feature data stream and perform azimuth estimation and positioning of the source to be measured.

2. The complex electromagnetic environment electromagnetic compatibility field measurement system according to claim 1, characterized in that, The antenna array includes multiple antenna elements, which are used to transmit the received electromagnetic signals to the programmable on-chip system simultaneously through the low-noise amplifier module and the radio frequency transceiver.

3. The complex electromagnetic environment electromagnetic compatibility field measurement system according to claim 2, characterized in that, The programmable system-on-chip includes an FPGA for parallel preprocessing of the data stream.

4. The complex electromagnetic environment electromagnetic compatibility field measurement system according to claim 3, characterized in that, The FPGA includes a programmable logic unit (PL), a processing system (PS), and a configuration module. The configuration module is used to initialize the radio frequency transceiver to initialize the logic units of the programmable logic unit (PL).

5. The complex electromagnetic environment electromagnetic compatibility field measurement system according to claim 4, characterized in that, The FPGA also includes a serial port module for the processing system PS to interact with the host computer.

6. The field measurement system for electromagnetic compatibility in complex electromagnetic environments according to claim 5, characterized in that, The FPGA also includes a digital signal preprocessing module, which is used for the programmable logic PL to transmit and receive digital signals with the radio frequency transceiver.

7. The complex electromagnetic environment electromagnetic compatibility field measurement system according to claim 6, characterized in that, The FPGA also includes a PL-PS communication module, used to send the data blocks processed by the programmable logic PL to a designated buffer of the processing system PS.

8. The complex electromagnetic environment electromagnetic compatibility field measurement system according to claim 7, characterized in that, The FPGA also includes an Ethernet module for sending the feature data stream preprocessed by the processing system PS to the host computer.

9. The complex electromagnetic environment electromagnetic compatibility field measurement system according to any one of claims 1-8, characterized in that, The host computer has the following built-in features: A buffer module is used to shape the feature data stream; Automatic gain control (AGC) module is used to dynamically adjust the gain of the shaped signal; The autocorrelation function calculation module is used to calculate the autocorrelation matrix and eigenvalue decomposition of the effective feature data in the buffer module, and determine the corresponding noise subspace based on the magnitude of the eigenvalues. The peak search module is used to determine the azimuth angle of the incoming wave of the source to be measured by using the peak search algorithm on the signal output by the automatic gain control (AGC) module.

10. The field measurement system for electromagnetic compatibility in complex electromagnetic environments according to claim 9, characterized in that, The peak search algorithm is as follows: based on the signal output by the automatic gain control (AGC) module, a manifold matrix is ​​constructed and multiplied with the noise subspace to obtain the MUSIC spectral function, and the most prominent peak in the spectrum is found to determine the azimuth angle of the incoming wave.

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