Radar signal receiving and transmitting integrated positioning method based on information metasurface antenna
Through the integrated transmissive metasurface and planar array antenna, combined with the ringer to achieve integrated signal transmission and reception, the problems of existing information metasurface systems in miniaturization and beam regulation accuracy are solved, and efficient and real-time intelligent sensing positioning function is realized.
Patent Information
- Application Number
- CN202510459682.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-14
- Publication Date
- 2025-05-23
AI Technical Summary
The existing information metasurface system relies on horn antennas, resulting in an increase in the system profile, which is not conducive to the development of miniaturization and compact space applications. The traditional reflected or transmissive information metasurface is limited in beam regulation accuracy, affecting the implementation of communication or perception functions.
The integrated radar signal transceiver positioning method based on information metasurface antenna is adopted. By integrating transceiver and planar array antennas, an integrated and integrated reconstructible information metasurface antenna design is realized, avoiding the use of feed horns, and integrating signal transceiver through a circulator.
The system is miniaturized, the accuracy of perceived positioning and signal quality are improved, the energy loss during transmission is reduced, and the system is adaptable and robust in complex environments.
Smart Images
Figure CN120028796A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of wireless sensing technology, and in particular to a radar signal transceiver integrated positioning method based on an information metasurface antenna. Background Art
[0002] Metasurfaces have subwavelength characteristics. By cleverly designing unit structures or array arrangements, material properties that do not exist in nature or are difficult to achieve can be obtained. Early metasurfaces were only used as unconventional media for regulating electromagnetic physical phenomena. Their functions were relatively simple and it was difficult to dynamically regulate electromagnetic waves. To overcome this limitation, Professor Cui Tiejun's team at Southeast University proposed the concept of digitally coded metasurfaces in 2014, realizing complex functions such as beamforming. Subsequently, by integrating adjustable components, tunable materials, and using control technologies such as single-chip microcomputers and FPGAs, the bottleneck of traditional metasurfaces with solidified functions and unable to regulate electromagnetic waves in real time was broken. Furthermore, combined with digital signal processing technology, Professor Cui's team proposed the concept of information metasurfaces. Information metasurfaces can not only realize information modulation, but also perform real-time perception, which has promoted the innovative development of electromagnetic wave control technology and provided new hardware support for the construction of electronic information systems such as wireless communications, intelligent perception, and microwave imaging.
[0003] However, current information metasurfaces mainly include two types: intelligent reflective surfaces and transmissive information metasurfaces. Both rely on horn antennas as excitation sources, which increases the system profile and is not conducive to miniaturization and compact space applications. Moreover, electromagnetic waves are prone to energy attenuation during propagation and are affected by intermediate obstructions, which limits the accuracy of beam control in traditional reflective or transmissive information metasurfaces, thus affecting the realization of communication or perception functions. Therefore, it is urgent to develop an active information metasurface device that can integrate radiation and scattering functions.
[0004] In addition, the perception and positioning system based on smart metasurfaces usually requires additional feed horns and receiving antennas. When there is occlusion between the excitation source and the metasurface, the metasurface will not be able to achieve the expected angle control, thus affecting the accuracy of perception and positioning; and the placement of the receiving antenna is crucial to the effective reception of the signal, which becomes a key factor limiting the stable operation of the system. On the other hand, many studies achieve perception detection by loading sensors on the metasurface, which increases the power consumption of the system. Therefore, it is urgent to explore a perception and positioning method that can realize the integration of signal transmission and reception. This not only helps to miniaturize the system, but also effectively reduces the energy loss during transmission, improves the perception distance and signal quality, and enhances the adaptability and robustness of the system in complex environments. Summary of the invention
[0005] The purpose of the present invention is to provide a radar signal transceiver integrated positioning method based on an information metasurface antenna, which does not require additional feed speakers, receiving antennas, or wearable devices to achieve intelligent perception and positioning of the human body.
[0006] To achieve the above object, the present invention provides a radar signal transceiver integrated positioning method based on an information metasurface antenna, comprising:
[0007] The signal transmission and reception module includes a universal software radio peripheral (USRP) and an integrated, reconfigurable information metasurface antenna. The USRP is used as an excitation source and generates a linear frequency modulation signal, and the information metasurface antenna is used to transmit electromagnetic scanning signals and receive target reflection signals; the coding control module is used to provide dynamic coding for the metasurface; and the signal processing module is used to process the reflected echo in real time to achieve target perception and positioning.
[0008] Preferably, the coding control module includes a PC and a controller, the PC is used to calculate the beamforming coding, and the controller is used to control the coding state of the metasurface.
[0009] Preferably, the signal processing module is used to perform real-time processing of the reflected echo to achieve target perception and positioning, specifically including: the signal processing module transmits the reflected echo received by the information metasurface antenna to the USRP for signal processing and analysis; the high reference level and the low reference level of the signal received in the unmanned scene are defined as the environmental reference level; the signal processing module performs transient measurement on the signal received in the manned scene to obtain the high reference level and the low reference level of the reflected signal in the manned scene; the high reference level and the low reference level in the manned scene and the environmental reference level are differentially operated respectively to obtain the fluctuation amplitude of the reflected signal and compare it with a threshold value. If the absolute value of the environmental fluctuation amplitude is greater than the threshold value, it means that there is someone in the information metasurface antenna beam scanning angle, otherwise there is no one.
[0010] Preferably, the information metasurface antenna includes a transmissive metasurface, a planar array antenna and a circulator, the planar array antenna is used to perform equivalent plane wave excitation on the transmissive metasurface, and the circulator is used to realize integrated signal transmission and reception.
[0011] Preferably, the transmissive metasurface includes: 16×16 basic units, the basic unit includes four layers of metal, three layers of dielectric and two PIN diodes, and the unit size is 15 mm; 16 basic units located in the same row form a row subarray, and the metasurface units located in the same row subarray are provided with the same feeding voltage by the metasurface controller.
[0012] Preferably, the transmissive metasurface includes two working states: the working state in which the first PIN diode is turned on and the second PIN diode is turned off is positioned as state "0"; the opposite working state is defined as state "1".
[0013] Preferably, the planar array antenna includes: 16×16 array units, and the unit size is 15 mm; the antenna array adopts a power division feeding method to achieve equivalent plane wave excitation of the transmissive metasurface.
[0014] Preferably, the circulator is used to realize the integrated transmission and reception of the information metasurface antenna.
[0015] Preferably, in both working states, the transmission amplitude of the transmissive metasurface at 5.77-5.83 GHz is greater than 0.8, and the phase difference is maintained at 180°.
[0016] Preferably, the planar array antenna has an S frequency of 5.77-5.83 GHz. 11 Less than -10dB.
[0017] According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects:
[0018] The present invention provides a radar signal transceiver integrated positioning method based on an information metasurface antenna. By integrating a transmission metasurface and a planar array antenna, an integrated, integrated reconfigurable information metasurface antenna design is realized, the use of a feed horn is avoided, and the system is miniaturized; by integrating a circulator at the antenna feed port, the transceiver of the information metasurface antenna is integrated. Moreover, the intelligent sensing function provided by the method is directly completed by the metasurface antenna without any sensor or wearable device, which provides a new idea for an efficient, real-time, contactless intelligent sensing system, and has broad application prospects in the fields of smart home (health monitoring and early warning) and smart transportation (obstacle detection). BRIEF DESCRIPTION OF THE DRAWINGS
[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.
[0020] Figure 1 A schematic flow chart of the integrated radar signal transceiver positioning method based on the information metasurface antenna provided by the present invention.
[0021] Figure 2Figure 1 shows the transmission metasurface and planar array antenna used in the present invention. (a) Schematic diagram of the transmission metasurface unit structure, (b) amplitude-frequency simulation curve of the transmission metasurface unit, (c) phase-frequency simulation curve of the transmission metasurface unit, (d) schematic diagram of the planar array antenna structure, (e) S 11 Performance curves.
[0022] Figure 3 The far-field radiation results of the information metasurface antenna used in the present invention under different coding states (0°, 15°, 30°, 45° and 60°).
[0023] Figure 4 A schematic diagram of the radar signal transceiver integrated positioning method based on the information metasurface antenna provided by the present invention.
[0024] Figure 5 Radar signals transmitted and received by the information metasurface antenna used in the present invention. (a) Baseband waveform of a linear frequency modulation signal with a length of five cycles transmitted by the information metasurface antenna, (b) Time-frequency curve corresponding to the transmitted signal, (c) Waveform of a linear frequency modulation signal with a length of five cycles received by the information metasurface antenna, (b) Time-frequency curve corresponding to the received signal.
[0025] Figure 6 The present invention provides three sets of reflected echo data collected in the unmanned and manned environments. In the manned environment, the man walks in the 0° direction for 0-0.1s, in the 15° direction for 0.1-0.2s, in the -30° direction for 0.2-0.3s, in the -45° direction for 0.3-0.4s, and in the 60° direction for 0.4-0.5s. (a) The environment is unmanned, and the information metasurface antenna scans at an angle of 0°; (b) The environment is manned, and the information metasurface antenna scans at an angle of 0°; (c) The environment is unmanned, and the information metasurface antenna scans at an angle of 15°; (d) The environment is manned, and the information metasurface antenna scans at an angle of 15°; (e) The environment is unmanned, and the information metasurface antenna scans at an angle of 45°; (f) The environment is manned, and the information metasurface antenna scans at an angle of 45°. DETAILED DESCRIPTION
[0026] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions 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.
[0027] The purpose of the present invention is to provide a radar signal transceiver integrated positioning method based on an information metasurface antenna, which can realize the perception and positioning of the human body without the need for additional feed horns and receiving antennas.
[0028] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.
[0029] like Figure 1 As shown, the present invention provides a radar signal transceiver integrated positioning method based on an information metasurface antenna, including a signal transmitting and receiving module, wherein the USRP is used as an excitation source and generates a linear frequency modulation signal, and the information metasurface antenna is used to transmit an electromagnetic scanning signal and receive a target reflection signal; a coding control module is used to provide dynamic coding for the metasurface; and a signal processing module is used to perform real-time processing of the reflected echo to achieve target perception and positioning.
[0030] The coding control module includes a PC and a controller, the PC is used to calculate beamforming coding, and the controller is used to control the coding state of the metasurface.
[0031] Specifically, the signal processing module is used to perform real-time processing of the reflected echo to achieve target perception and positioning, specifically including: the signal processing module transmits the reflected echo received by the information metasurface antenna to the USRP for signal processing and analysis, and defines the high reference level and low reference level of the signal received in an unmanned scene as the environmental reference level; the signal processing module performs transient measurement on the signal received in a manned scene to obtain the high reference level and low reference level of the reflected signal in the manned scene; the high reference level and low reference level in the manned scene and the environmental reference level are differentially operated respectively to obtain the fluctuation amplitude of the reflected signal and compare it with a threshold. If the absolute value of the environmental fluctuation amplitude is greater than the threshold, it means that there is someone in the information metasurface antenna beam scanning angle, otherwise there is no one.
[0032] Among them, the information metasurface antenna includes a transmissive metasurface, a planar array antenna and a circulator. The planar array antenna is used to perform equivalent plane wave excitation on the transmissive metasurface, and the circulator is used to realize the integrated transmission and reception of signals.
[0033] Specifically, the transmission metasurface includes: 16×16 basic units, 16 basic units located in the same row form a row subarray, and the metasurface units located in the same row subarray are provided with the same feeding voltage by the metasurface controller. Figure 2 As shown in (a), the basic unit includes four metal layers, three dielectric layers and two PIN diodes, and the unit size is 15mm.
[0034] The transmissive metasurface includes two working states: the working state in which the first PIN diode is turned on and the second PIN diode is turned off is defined as state "0"; the opposite working state is defined as state "1". Figure 2 As shown in (b) and (c), in the two working conditions, the transmission amplitude of the transmission metasurface at 5.77-5.83 GHz is greater than 0.8, and the phase difference is maintained at 180°.
[0035] Specifically, the planar array antenna includes: 16×16 array units, and the unit size is 15 mm. Figure 2 As shown in (d), the antenna array adopts a power division feeding method to achieve equivalent plane wave excitation of the transmissive metasurface.
[0036] In addition, if Figure 2 As shown in (e), the planar array antenna has an S frequency of 5.77-5.83 GHz. 11 Less than -10dB.
[0037] like Figure 3 As shown in the figure, the far-field radiation results of the information metasurface antenna under different coding states (0°, 15°, 30°, 45° and 60°) are given. Since the transmission metasurface adopts column-controlled feeding and the equivalent plane wave excitation is provided by the planar array antenna, the far-field radiation is a symmetrical dual beam. The far-field radiation results prove the beamforming capability of the information metasurface antenna and provide a device basis for target detection at different angles.
[0038] Figure 4 The principle diagram of the radar signal transceiver integrated positioning method based on the information metasurface antenna of this embodiment is given. This embodiment uses USRP as an excitation source to generate a linear frequency modulation signal, and transmits it through the transmitting channel of the information metasurface antenna. At the same time, a PC is used to operate the controller to apply different coding sequences to the transmission metasurface to realize the beam scanning function. Subsequently, after the electromagnetic wave is reflected by the target, it is received by the receiving channel of the information metasurface antenna and transmitted back to the USRP to obtain the baseband waveform of the reflected echo. By performing transient measurement on the echo signal and comparing it with the preset reference level threshold, it is determined whether there is a target at the scanning angle, and finally high-precision perception and positioning of the target are achieved.
[0039] Figure 5 (a) and (b) respectively show the baseband waveform of the linear frequency modulation signal transmitted by the information metasurface antenna used in the present invention in the 0° coding state and its corresponding time-frequency curve. The figure shows five cycles of the signal with a total duration of 1.25ms. The time-frequency relationship of the transmitted signal is defined as: f(t) = 2 8 ×t Hz, where t ranges from 0 to 1.25 ms. Figure 5 (c) and (d) show the baseband waveform and its corresponding time-frequency curve received by the information metasurface antenna in the 0° coding state under the same conditions. The experimental results show that the received signal has a time delay of about 0.25ms relative to the transmitted signal, but maintains the baseband waveform and time-frequency modulation characteristics consistent with the transmitted signal. However, since electromagnetic waves will attenuate during propagation, especially when encountering environmental obstacles such as walls and reflections, this attenuation effect is more significant, resulting in the amplitude of the received signal being weakened compared to the transmitted signal. These experimental data verify the effectiveness and reliability of the integrated radar signal transmission and reception method based on the information metasurface antenna proposed in the present invention. This method can maintain stable transmission and accurate reception of signals in complex actual environments, providing strong technical support for achieving high-precision target detection and positioning.
[0040] In order to further verify the accuracy of the integrated radar signal transceiver positioning method based on the information metasurface antenna proposed in the present invention, the reflection echo data collection experiment was carried out in the unmanned and manned environments. In the manned environment, the target person's moving direction in different time periods is as follows: walking along the 0° direction within 0-0.1s, turning to the 15° direction within 0.1-0.2s, moving to the -30° direction within 0.2-0.3s, continuing to walk in the -45° direction within 0.3-0.4s, and finally turning to the 60° direction within 0.4-0.5s. Figure 6 (a) to Figure 6 (f) shows the reflection echo curves of the information metasurface antenna at different scanning angles (0°, 15°, 45°) in unmanned and manned environments. The specific analysis is as follows:
[0041] Figure 6 (a) and Figure 6 (b): At a scanning angle of 0°, the comparison of the reflected echo curves of the environment with and without people shows that the movement of people within 0-0.1s causes obvious fluctuations in the waveform, with a fluctuation amplitude of 0.08.
[0042] Figure 6 (c) and Figure 6 (d) At a scanning angle of 15°, the comparison of the reflected echo curves in an unmanned environment and a human environment shows that the movement of a human within 0.1-0.2s also causes waveform fluctuations with an amplitude of 0.03.
[0043] Figure 6 (e) and Figure 6 (f): At a scanning angle of 45°, the comparison of the reflected echo curves of the environment with and without people reveals that the movement of people within 0.3-0.4s causes waveform fluctuations with an amplitude of 0.07.
[0044] The experimental results show that only when the target person is located at the scanning angle of the information metasurface antenna and moves, the waveform of the received signal will produce a significant fluctuation of more than 0.02. Therefore, we set the comparison threshold to 0.02, that is, when the absolute value of the difference between the transient signal of the received signal and the environmental reference level is greater than 0.02, it can be determined that there is human activity at the scanning angle; otherwise, it is considered that there is no one. In addition, in this embodiment, each scanning angle only takes 0.1s to complete the accurate detection of the target at that angle. By designing a dynamic scanning beam, all targets within the range of ±60° can be covered within 0.5s, thereby realizing real-time monitoring of targets within the range of ±60° in space. These experimental results fully demonstrate the feasibility and efficiency of the integrated radar signal receiving and transmitting positioning method based on the information metasurface antenna proposed in the present invention in practical applications.
[0045] 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 replace some or all of the technical features therein by equivalents. 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 radar signal transceiver integrated positioning method based on information metasurface antenna, characterized in that: include: The signal transmission and reception module includes a universal software radio peripheral (USRP) and an integrated, reconfigurable information metasurface antenna. The USRP is used as an excitation source and generates a linear frequency modulation signal, and the information metasurface antenna is used to transmit an electromagnetic scanning signal and receive a target reflection signal; A coding control module, used to provide dynamic coding for the metasurface; The signal processing module is used to process the reflected echo in real time to achieve target perception and positioning.
2. The radar signal transceiver integrated positioning method based on information metasurface antenna according to claim 1 is characterized in that: The coding control module includes a PC and a controller, the PC is used to calculate beamforming coding, and the controller is used to control the coding state of the metasurface.
3. The radar signal transceiver integrated positioning method based on information metasurface antenna according to claim 1 is characterized in that: The signal processing module is used to process the reflected echo in real time to achieve target perception and positioning, specifically including: The signal processing module transmits the reflected echo received by the information metasurface antenna to the USRP for signal processing and analysis, and defines the high reference level and the low reference level of the signal received in the unmanned scene as the environmental reference level; The signal processing module performs transient measurement on the signal received in the scene with people, and obtains a high reference level and a low reference level of the reflected signal in the scene with people; The high reference level and the low reference level in the human scene are differentially operated with the environmental reference level to obtain the fluctuation amplitude of the reflected signal and compare it with a threshold. If the absolute value of the environmental fluctuation amplitude is greater than the threshold, it means that there is someone in the information metasurface antenna beam scanning angle, otherwise there is no one.
4. The radar signal transceiver integrated positioning method based on information metasurface antenna according to claim 1 is characterized in that: The information metasurface antenna includes a transmissive metasurface, a planar array antenna and a circulator. The planar array antenna is used to perform equivalent plane wave excitation on the transmissive metasurface, and the circulator is used to realize the integrated transmission and reception of signals.
5. The radar signal transceiver integrated positioning method based on information metasurface antenna according to claim 4 is characterized in that: The transmission metasurface includes: 16×16 basic units, each basic unit includes four layers of metal, three layers of dielectrics and two PIN diodes, and the unit size is 15 mm; 16 basic units located in the same row form a row subarray, and the metasurface units located in the same row subarray are provided with the same feeding voltage by the metasurface controller.
6. The radar signal transceiver integrated positioning method based on information metasurface antenna according to claim 4 is characterized in that: The transmissive metasurface includes two working states: the working state in which the first PIN diode is turned on and the second PIN diode is turned off is defined as state "0"; the opposite working state is defined as state "1".
7. The radar signal transceiver integrated positioning method based on information metasurface antenna according to claim 4 is characterized in that: The planar array antenna includes: 16×16 array units, and the unit size is 15 mm; the antenna array adopts a power division feeding method to achieve equivalent plane wave excitation of the transmission metasurface.
8. The radar signal transceiver integrated positioning method based on information metasurface antenna according to claim 4 is characterized in that: The circulator is used to realize the integrated transmission and reception of the information metasurface antenna.
9. The radar signal transceiver integrated positioning method based on information metasurface antenna according to claim 6 is characterized in that: In the two working states, the transmission amplitude of the transmission metasurface at 5.77-5.83 GHz is greater than 0.8, and the phase difference is maintained at 180°.
10. The radar signal transceiver integrated positioning method based on information metasurface antenna according to claim 7, characterized in that: The planar array antenna has an S frequency of 5.77-5.83 GHz. 11 Less than -10dB.