Distributed microwave photon high-precision distance measuring device

Abstract

The invention discloses a distributed microwave photon high-precision distance measuring device, which is characterized in that a distributed multi-antenna network transmits and receives broadband distance measuring signals and constructs a multi-antenna cooperative measuring network, and an optical fiber transmission time delay control module performs broadband signal time frequency calibration of multi-antenna channel optical fiber transmission; the broadband signal modulation and demodulation module is located in a central station to carry out electro-optical modulation and photoelectric conversion on broadband ranging signals, and the analog-to-digital conversion module converts analog radio frequency ranging signals received by the multi-antenna channel into digital signals and carries out digital acquisition and processing. The digital signal processing module carries out multi-antenna spacing measurement through a pulse signal and broadband chirp signal ranging algorithm. And high-precision and real-time multi-antenna spacing measurement and position calculation are realized by fusing a wired optical fiber transmission stable-time calibration technology and a wireless multi-antenna spacing measurement technology.

Description

Technical Field

[0001] The present application relates to the field of signal processing technology, and in particular to a distributed microwave photon high-precision ranging device. Background Art

[0002] Distributed multi-antenna systems (such as MIMO systems) have been widely used in the fields of new generation wireless communications, advanced passive detection, etc. due to their advantages of distributed layout and centralized processing. In these systems, accurate and reliable time-frequency synchronization is essential to achieve coherent synthesis of multi-antenna signals. However, since distributed multi-antenna systems are usually deployed in unmanned areas, extreme weather factors (such as strong winds, heavy snow, etc.) may cause the antenna to jitter or shift, thereby introducing non-negligible phase errors. This phase error will directly affect the time-frequency synchronization of the transmitted signal, thereby reducing the performance and reliability of the system.

[0003] To solve this problem, the traditional method is usually to set up one or more auxiliary antennas in the system and calibrate the phase error caused by antenna jitter at irregular intervals. However, this method has the following disadvantages: high cost, adding auxiliary antennas increases the hardware cost of the system; non-real-time, irregular calibration cannot meet the needs of dynamic access and real-time transmission of broadband signals; low accuracy, traditional calibration methods are difficult to achieve high-precision phase error correction requirements.

[0004] Therefore, there is an urgent need to study an active, high-precision distributed antenna spacing measurement technology that can monitor and correct the phase error caused by antenna jitter in real time under extreme conditions. Summary of the invention

[0005] The purpose of this application is to overcome the existing technical defects and provide a distributed microwave photon high-precision ranging device, which realizes high-precision, real-time multi-antenna spacing measurement and position solution by integrating wired optical fiber transmission steady-time calibration technology and wireless multi-antenna spacing measurement technology.

[0006] The purpose of this application is achieved through the following technical solutions:

[0007] In a first aspect, the present application proposes a distributed microwave photon high-precision ranging device, the device comprising a distributed multi-antenna network, an optical fiber transmission delay control module, a broadband signal modulation and demodulation module, an analog-to-digital conversion module, and a digital signal processing module connected in sequence through an optical fiber link;

[0008] Distributed multi-antenna network, used to transmit and receive broadband ranging signals and build a multi-antenna collaborative measurement network;

[0009] Optical fiber transmission delay control module, used for broadband signal time and frequency calibration of multi-antenna channel optical fiber transmission;

[0010] The broadband signal modulation and demodulation module is located in the central station and is used for electro-optical modulation and photoelectric conversion of broadband ranging signals.

[0011] The analog-to-digital conversion module is used to convert the analog radio frequency ranging signals received by the multi-antenna channels into digital signals, and perform digital acquisition and processing;

[0012] Digital signal processing module for multi-antenna spacing measurement using pulse signal and broadband chirp signal ranging algorithms.

[0013] In one possible implementation, the distributed multi-antenna network is composed of distributed multi-antenna unit apertures, including electro-optical and opto-electronic conversion modules, microwave components, and omnidirectional antennas with dual transceiver functions;

[0014] Omnidirectional antenna, used for transmitting and receiving broadband ranging signals between multiple antennas;

[0015] The electro-optical and photoelectric conversion module is used to modulate the received broadband ranging signal into the optical signal, and convert the optical signal transmitted from the central end into the ranging radio frequency signal through photoelectric detection;

[0016] Microwave components that provide power transmission, noise reception, and equalization.

[0017] In one possible implementation, the optical fiber link is used for bidirectional transmission of broadband ranging signals.

[0018] In a possible implementation manner, a feedback loop is further provided between the broadband signal modulation and demodulation module and the optical fiber transmission delay control module to provide delay feedback for the time-frequency calibration of the optical fiber link.

[0019] In a possible implementation, the electro-optical modulation of the broadband signal modulation and demodulation module selects external modulation, including a continuous wave light source and a broadband electro-optical modulator;

[0020] A continuous wave light source for providing an optical carrier;

[0021] A broadband electro-optical modulator is used to load an electrical signal onto an optical carrier so that the amplitude, phase or frequency of the optical carrier changes with the electrical signal.

[0022] In a possible implementation, the broadband signal modulation and demodulation module further includes a broadband photodetector, which is used to convert the received optical signal into an electrical signal.

[0023] In a possible implementation manner, the device further includes a digital signal processor or a central processing unit, which is used to process data from each antenna node and execute an algorithm.

[0024] In a possible implementation, the device further includes a synchronization control module, which is used to perform time synchronization among all antenna nodes, phase alignment, and signal coordination.

[0025] The above-mentioned main scheme of the present application and its further options can be freely combined to form multiple schemes, all of which are schemes that can be adopted and claimed for protection in the present application; and in the present application, (non-conflicting options) options and other options can also be freely combined. After understanding the scheme of the present application, those skilled in the art can understand that there are multiple combinations based on the prior art and common knowledge, all of which are technical schemes to be protected by the present application, and they are not exhaustively listed here.

[0026] The present application discloses a distributed microwave photon high-precision ranging device, a distributed multi-antenna network transmits and receives broadband ranging signals, and constructs a multi-antenna collaborative measurement network, an optical fiber transmission delay control module performs time-frequency calibration of broadband signals transmitted by optical fibers of multi-antenna channels, a broadband signal modulation and demodulation module is located at a central station to perform electro-optical modulation and photoelectric conversion of broadband ranging signals, an analog-to-digital conversion module converts analog radio frequency ranging signals received by multi-antenna channels into digital signals, and performs digital acquisition and processing, and a digital signal processing module performs multi-antenna spacing measurement through pulse signals and broadband chirp signal ranging algorithms. By integrating the wired optical fiber transmission steady-time calibration technology and the wireless multi-antenna spacing measurement technology, high-precision, real-time multi-antenna spacing measurement and position solution are achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0028] Figure 1 A distributed microwave photon high-precision ranging device proposed in an embodiment of the present application is shown. DETAILED DESCRIPTION

[0029] The following describes the embodiments of the present application through specific examples, and those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. The present application can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict.

[0030] Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making any creative work shall fall within the scope of protection of this application.

[0031] In the prior art, distributed multi-antenna systems are generally deployed in unmanned areas. When affected by extreme weather factors, the jitter and displacement of the antenna will cause non-negligible phase errors, which will directly affect the time-frequency synchronization of the transmission signal in the distributed multi-antenna system. Traditionally, one or more auxiliary antennas are usually set up to check the phase error caused by antenna jitter through irregular calibration. However, this method has the disadvantages of high cost, non-real-time, and low accuracy, which is very unfavorable for the dynamic access and real-time transmission of broadband signals in distributed multi-antenna systems.

[0032] Therefore, in order to address the shortcomings of the auxiliary antenna calibration method in a multi-antenna system, such as non-real-time and low accuracy, the embodiment of the present application proposes a distributed microwave photon high-precision ranging device, which is suitable for distributed multi-antenna high-precision ranging processing in radar, communication and other systems. It integrates the wired optical fiber transmission steady-time calibration technology with the wireless multi-antenna spacing measurement technology, and uses the wired optical fiber transmission steady-time calibration technology to achieve time-frequency calibration of long-distance, distributed multi-antenna broadband signals; uses the wireless multi-antenna spacing measurement technology to achieve spacing measurement and real-time position solution between distributed multi-antennas, which will be described in detail below.

[0033] Please refer to Figure 1 , Figure 1 A distributed microwave photon high-precision ranging device proposed in an embodiment of the present application is shown, which includes a distributed multi-antenna network, an optical fiber transmission delay control module, a broadband signal modulation and demodulation module, an analog-to-digital conversion module, and a digital signal processing module connected in sequence through an optical fiber link;

[0034] Distributed multi-antenna network, used to transmit and receive broadband ranging signals and build a multi-antenna collaborative measurement network;

[0035] Optical fiber transmission delay control module, used for broadband signal time and frequency calibration of multi-antenna channel optical fiber transmission;

[0036] The broadband signal modulation and demodulation module is located in the central station and is used for electro-optical modulation and photoelectric conversion of broadband ranging signals.

[0037] The analog-to-digital conversion module is used to convert the analog radio frequency ranging signals received by the multi-antenna channels into digital signals, and perform digital acquisition and processing;

[0038] Digital signal processing module for multi-antenna spacing measurement using pulse signal and broadband chirp signal ranging algorithms.

[0039] The distributed multi-antenna network can transmit and receive broadband ranging signals and build a multi-antenna collaborative measurement network. Each antenna aperture unit can transmit and receive signals independently or in coordination with other antennas, supporting the N-transmit-N-receive (N omnidirectional antennas) ranging mode. The optical fiber transmission delay control module can realize the time-frequency calibration of broadband signals for long-distance optical fiber transmission of multi-antenna channels. By accurately controlling the transmission delay of the optical fiber channel, the stable phase transmission of the broadband ranging signal is guaranteed, and the synchronization and coordination of the system are improved. The broadband signal modulation and demodulation module is located in the central station, corresponding to each antenna channel, to realize the electro-optical modulation and photoelectric conversion of the broadband ranging signal, ensuring the effective modulation and high-quality transmission of the signal. The analog-to-digital conversion module converts the analog RF ranging signal received by the multi-antenna channel into a digital signal, and completes digital acquisition and processing. The digital signal processing module realizes high-precision multi-antenna spacing measurement through pulse signals and broadband chirp signal ranging algorithms. It can not only perform pulse signal ranging, use short pulse signals to measure the relative distance between multiple antennas, but also perform broadband chirp signal ranging. Through the characteristics of broadband chirp signals, the resolution and accuracy of ranging are further improved.

[0040] The working process of the distributed microwave photon high-precision ranging device is as follows:

[0041] First, the central station generates a broadband ranging signal through a broadband signal modulation and demodulation module, and transmits it to each distributed antenna node through an optical fiber link.

[0042] Second, each antenna node receives the broadband ranging signal from the central station and broadcasts it through the omnidirectional antenna. Other antenna nodes receive these signals, forming an N-transmit-N-receive measurement network.

[0043] Third, the received ranging signal is transmitted back to the central station via the optical fiber link.

[0044] Fourth, the analog-to-digital conversion module converts the received analog radio frequency ranging signal into a digital signal.

[0045] Fifth, the digital signal processing module calculates and determines the precise distance between each antenna through the pulse signal and broadband chirp signal ranging algorithm.

[0046] Sixth, through the optical fiber transmission delay control module and feedback loop, the delay of multiple antenna channels is calibrated in real time to ensure signal synchronization and stability.

[0047] Seventh, based on the measured distributed multi-antenna spacing and positions, a real-time digital delay calibration algorithm is used to calibrate the phase inaccuracy caused by antenna jitter due to environmental factors, thereby improving the coherent synthesis accuracy of the distributed system.

[0048] By connecting the distributed multi-antenna network, optical fiber transmission delay control module, broadband signal modulation and demodulation module, analog-to-digital conversion module and digital signal processing module through optical fiber links, efficient transmission, stable phase modulation, precise measurement and real-time calibration of broadband ranging signals are achieved.

[0049] The distributed multi-antenna network consists of distributed multi-antenna unit apertures, including electro-optical and opto-electronic conversion modules, microwave components, and omnidirectional antennas with dual transmit and receive functions;

[0050] Omnidirectional antenna, used for transmitting and receiving broadband ranging signals between multiple antennas;

[0051] The electro-optical and photoelectric conversion module is used to modulate the received broadband ranging signal into the optical signal, and convert the optical signal transmitted from the central end into the ranging radio frequency signal through photoelectric detection;

[0052] Microwave components that provide power transmission, noise reception, and equalization.

[0053] The distributed multi-antenna network is mainly composed of multiple distributed antenna unit apertures. Each antenna unit can not only work independently, but also work in coordination with other units. The omnidirectional antenna has duplex transmission and reception capabilities, supporting the transmission and reception of broadband ranging signals between multiple antennas. It can capture signals from different directions in all directions, thereby ensuring the stability and reliability of signal transmission. The electro-optical and photoelectric conversion modules can perform electro-optical conversion, load the received broadband ranging signal onto the optical carrier through electro-optical modulation technology, and use optical fiber for long-distance lossless transmission. They can also perform photoelectric conversion, receive the optical signal transmitted through the optical fiber from the center end, and restore it to the original radio frequency (RF) ranging signal through the photoelectric detector, which can effectively reduce electromagnetic interference and improve the speed and quality of data transmission. The microwave component can provide high-power RF signal transmission capability to ensure that the signal strength is strong enough to reach the target location. It can also perform low-noise signal reception, reduce the impact of the external environment on the signal, improve the receiving sensitivity, and balance the signal to improve the channel characteristics and optimize the overall communication performance.

[0054] Optical fiber link for bidirectional transmission of broadband ranging signals.

[0055] The optical fiber link is mainly used for long-distance bidirectional transmission of broadband ranging signals to ensure stable phase transmission between multiple antenna channels. Specifically, it can achieve long-distance optical fiber stable phase transmission of broadband signals between multiple antenna channels and provide accurate wired time and frequency calibration. In each antenna channel, a feedback loop is established between the broadband signal modulation and demodulation module and the optical fiber transmission delay control module.

[0056] A feedback loop is also provided between the broadband signal modulation and demodulation module and the optical fiber transmission delay control module, for providing delay feedback for the time and frequency calibration of the optical fiber link.

[0057] The feedback loop connects the broadband signal modulation and demodulation module and the optical fiber transmission delay control module to provide delay feedback for the time and frequency calibration of the optical fiber link. By real-time monitoring and adjusting the transmission delay of the optical fiber channel, the stable phase transmission of the broadband ranging signal is ensured, thereby ensuring the synchronization and coordination of the system.

[0058] The electro-optical modulation of the broadband signal modulation and demodulation module selects external modulation, including a continuous wave light source and a broadband electro-optical modulator;

[0059] A continuous wave light source for providing an optical carrier;

[0060] A broadband electro-optical modulator is used to load an electrical signal onto an optical carrier so that the amplitude, phase or frequency of the optical carrier changes with the electrical signal.

[0061] The continuous wave light source provides a stable optical carrier, which can generate an optical signal with constant frequency and intensity. The broadband electro-optical modulator can load the electrical signal onto the optical carrier. By changing the amplitude, phase or frequency of the optical carrier, the optical signal carries the information of the electrical signal, ensuring high-quality transmission of the signal. It is also suitable for processing broadband ranging signals.

[0062] The broadband signal modulation and demodulation module also includes a broadband photodetector for converting the received optical signal into an electrical signal.

[0063] The broadband photodetector completes the photoelectric conversion, receives the optical signal after being transmitted through the optical fiber link, and converts it into an electrical signal.

[0064] The working principle of the broadband signal modulation and demodulation module is as follows: the optical carrier generated by the continuous wave light source enters the broadband electro-optical modulator. In the modulator, the electrical signal is loaded onto the optical carrier so that its characteristics (such as amplitude, phase or frequency) change with the electrical signal. The modulated optical signal is transmitted to the receiving end through the optical fiber link, received by the broadband photodetector and converted back into an electrical signal, thus realizing the complete transmission of information.

[0065] The device also includes a digital signal processor or a central processing unit for processing data from each antenna node and performing algorithm execution.

[0066] The digital signal processor or central processing unit is used to process the data from each antenna node and perform complex algorithm calculations such as delay calibration, signal processing, and distance measurement.

[0067] The synchronization control module can ensure the time synchronization between all antenna nodes, achieve precise phase alignment and signal coordination, and thus ensure the accuracy of ranging.

[0068] Compared with the prior art, the embodiments of the present application have the following beneficial effects:

[0069] By integrating the wired optical fiber transmission steady-state calibration technology and the wireless multi-antenna spacing measurement technology, sub-millimeter high-precision ranging is achieved, significantly improving the broadband array signal processing performance of distributed electronic information systems.

[0070] The use of direct modulation electro-optical conversion and single antenna transceiver function greatly reduces system cost and improves efficiency.

[0071] The coordinated work of each antenna node and real-time delay calibration enhances the reliability and stability of the system.

[0072] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A distributed microwave photon high-precision ranging device, characterized in that: The device comprises a distributed multi-antenna network, an optical fiber transmission delay control module, a broadband signal modulation and demodulation module, an analog-to-digital conversion module, and a digital signal processing module, which are sequentially connected via an optical fiber link; Distributed multi-antenna network, used to transmit and receive broadband ranging signals and build a multi-antenna collaborative measurement network; Optical fiber transmission delay control module, used for broadband signal time and frequency calibration of multi-antenna channel optical fiber transmission; The broadband signal modulation and demodulation module is located in the central station and is used for electro-optical modulation and photoelectric conversion of broadband ranging signals. The analog-to-digital conversion module is used to convert the analog radio frequency ranging signals received by the multi-antenna channels into digital signals, and perform digital acquisition and processing; Digital signal processing module for multi-antenna spacing measurement using pulse signal and broadband chirp signal ranging algorithms.

2. The distributed microwave photon high-precision ranging device according to claim 1, characterized in that: The distributed multi-antenna network is composed of distributed multi-antenna unit apertures, including electro-optical and optoelectronic conversion modules, microwave components, and omnidirectional antennas with dual transceiver functions; Omnidirectional antenna, used for transmitting and receiving broadband ranging signals between multiple antennas; The electro-optical and photoelectric conversion module is used to modulate the received broadband ranging signal into the optical signal, and convert the optical signal transmitted from the central end into the ranging radio frequency signal through photoelectric detection; Microwave components that provide power transmission, noise reception, and equalization.

3. The distributed microwave photon high-precision ranging device according to claim 1, characterized in that: Optical fiber link for bidirectional transmission of broadband ranging signals.

4. The distributed microwave photon high-precision ranging device according to claim 1, characterized in that: A feedback loop is also provided between the broadband signal modulation and demodulation module and the optical fiber transmission delay control module, for providing delay feedback for the time and frequency calibration of the optical fiber link.

5. The distributed microwave photon high-precision ranging device according to claim 1, characterized in that: The electro-optical modulation of the broadband signal modulation and demodulation module selects external modulation, including a continuous wave light source and a broadband electro-optical modulator; A continuous wave light source for providing an optical carrier; A broadband electro-optical modulator is used to load an electrical signal onto an optical carrier so that the amplitude, phase or frequency of the optical carrier changes with the electrical signal.

6. The distributed microwave photon high-precision ranging device according to claim 5, characterized in that: The broadband signal modulation and demodulation module also includes a broadband photodetector for converting the received optical signal into an electrical signal.

7. The distributed microwave photon high-precision ranging device according to claim 5, characterized in that: The device also includes a digital signal processor or a central processing unit, which is used to process data from each antenna node and execute an algorithm.

8. The distributed microwave photon high-precision ranging device according to claim 5, characterized in that: The device also includes a synchronization control module, which is used to perform time synchronization among all antenna nodes, phase alignment and signal coordination.

Images