A navigation high-precision multi-beam antenna

Abstract

This application relates to a navigation high-precision multi-beam antenna. Specifically, it consists of a multi-beam antenna module, a multi-channel radio frequency module, and an anti-interference digital module. The multi-beam antenna module is composed of multiple fixed-pointing narrow-beam units. Each beam has a stable phase center and sidelobe suppression ability, and each narrow-beam unit can independently receive signals. The signals received by all beams enter the anti-interference digital module after being frequency-converted, filtered, and sampled by the multi-channel radio frequency module. The anti-interference digital module assigns the reception weight values of each signal according to the signal correlation results and flexibly switches between beams, thereby completing the stable reception of signals. The present invention can effectively solve the high-precision problem in an interference environment.

Description

Technical Field

[0001] This application relates to the technical field of navigation antennas, and particularly to a high-precision multi-beam navigation antenna. Background Art

[0002] The global satellite navigation system is a space-based radio navigation system that can provide three-dimensional position and time information for ground, air, and medium- and low-earth orbit satellite users. It has the advantages of wide coverage, high precision, and all-weather operation, and plays an increasingly important role in core fields such as military, aviation, and life safety.

[0003] As an important part of the ground segment of the satellite navigation system, the monitoring station plays a decisive role in satellite orbit and clock error resolution, and the performance of the monitoring receiving antenna is one of the main factors. However, since the signals of the global satellite navigation system are very weak when reaching the ground, the signals received by the monitoring receiving antenna are extremely vulnerable to external environmental interference. Therefore, anti-interference is an unavoidable issue in all navigation application scenarios, especially the anti-interference problem of high-precision antennas has no good solution. For traditional omnidirectional high-precision antennas, they do not have the ability to resist broadband suppression interference, and weak electromagnetic interference can cause the receiver to stop working; while using an antenna array for anti-interference cannot well solve the problems of phase center fluctuation and multipath suppression, resulting in a decline in high-precision performance. Therefore, the high-precision problem in the current interference environment cannot be effectively solved. Summary of the Invention

[0004] Based on this, it is necessary to provide a high-precision multi-beam navigation antenna for the above technical problems.

[0005] A high-precision multi-beam navigation antenna, the multi-beam antenna comprising: a multi-beam antenna module, a multi-channel radio frequency module, and an anti-interference digital module;

[0006] The multi-beam antenna module is composed of a plurality of narrow-beam antenna units with fixed directions. The narrow beams formed by each narrow-beam antenna unit are closely arranged, and the beam coverage ranges overlap with each other to jointly complete the coverage of the upper hemisphere, so as to equivalently realize an omnidirectional beam;

[0007] The multi-channel radio frequency module is composed of radio frequency channels with the same number as the narrow-beam antenna units. The radio frequency channels are used to perform frequency conversion, filtering, and sampling on the beam reception signals output by the multi-beam antenna module;

[0008] The anti-interference digital module is used to select the beam with the strongest signal relative to the interference for capture according to the power and spatial distribution of the signal and the interference, so as to realize the anti-interference function.

[0009] In one embodiment, the multi-beam antenna module is composed of multiple narrow-beam antenna units with fixed pointing directions. The narrow beams formed by each antenna unit are closely arranged, and the beam coverage ranges overlap with each other to jointly complete the beam coverage of the upper hemisphere, equivalently realizing an omnidirectional beam. The antenna unit realizes the reception of broadband signals in a fixed-pointing area, with its operating frequency covering all satellite navigation frequency points, a stable phase center within the beam range, and a low sidelobe level. Each single antenna unit integrates a filter, a limiter, and a low-noise amplifier module, and has the functions of limiting the received signal, low-noise amplification, and filtering. The limiting function is used to limit the output amplitude under the condition of extremely strong power in the band. The amplification function is used to amplify the input signal to the target level without distortion. The filtering function is used to filter out-of-band interference signals.

[0010] In one embodiment, the anti-jamming digital module selects the beam with the strongest signal relative to the interference according to the power and spatial distribution of the signal and the interference, and allocates it to the navigation receiver for tracking processing. For the incident signal of a single satellite, the sampled signals of all N beams of the receiving antenna are first weighted by w. Then, the signals of each beam are correlated and accumulated in two paths, I and Q, with the local reference signal. Next, the correlation accumulation values of each beam are compared, and the beam with the largest accumulation value is selected as the beam for receiving the satellite signal, and the weight value of this beam is set to 1, while the weight values of other beams are set to 0, thus realizing the selection of the optimal anti-jamming beam. Finally, the weighted acquisition information is transmitted to the navigation receiver for signal tracking and positioning solution processing.

[0011] In one embodiment, the multi-beam antenna module consists of a multi-beam Luneburg lens antenna and a low-noise amplifier module group. The multi-beam Luneburg lens antenna is composed of a spherical Luneburg lens and a feed array. The feed array is composed of multiple identical broadband right-hand circularly polarized antenna units, which are placed at the surface focal position of the spherical Luneburg lens to realize the characteristics of multiple narrow beams with fixed pointing directions.

[0012] In one embodiment, the spherical Luneburg lens is composed of 4 discrete dielectric spheres with different radii and dielectric constants. The first layer is a homogeneous dielectric sphere, and the ratio of its radius to the maximum radius is 0.53. The last three layers are designed according to the approximate equal-thickness layering method. The feed array is composed of 34 broadband right-hand circularly polarized antenna units, which are evenly distributed around the Luneburg lens and are divided into four layers in total. There is 1 antenna unit in the first layer, 6 antenna units in the second layer, 12 antenna units in the third layer, and 15 antenna units in the fourth layer. The included angle between the antenna units between layers is the 3dB beam width after beam focusing. The broadband right-hand circularly polarized antenna units within the layer are evenly distributed at the same rotation angle according to the antenna unit size and the circumference of the circle. The feed array adjusts the distance from the outer surface of the Luneburg lens to ensure that the feed spacing is greater than 0.5 wavelengths.

[0013] In one embodiment, the multi-beam antenna module further includes: a low-noise amplifier module group; the low-noise amplifier module group includes a plurality of independent low-noise amplifier modules, which are connected to the output ports of the multi-beam Luneburg lens antenna; each low-noise amplifier module has a signal input port, a signal output port, and a power supply and monitoring interface. The internal of the low-noise amplifier module is composed of a limiting circuit, a pre-filtering circuit, a low-noise amplification circuit, a post-filtering circuit, and a power supply and monitoring circuit. The pre-filtering circuit, the limiting circuit, the low-noise amplification circuit, and the post-filtering circuit are connected in sequence. The pre-filtering circuit is connected to the signal input port, the post-filtering circuit is connected to the signal output port, and the power supply and monitoring circuit is connected to the power supply and monitoring interface.

[0014] In one embodiment, the multi-channel radio frequency module is composed of a plurality of independent radio frequency channels; each of the radio frequency channels includes: a frequency converter and a sampler.

[0015] In one embodiment, the frequency converter includes an input signal filtering module, a power adjustment module, a local oscillator module, a frequency conversion module, an output signal filtering module, a comprehensive control module, and a power supply module, and is composed of a signal input port, a signal output port, a local oscillator input interface, a power supply interface, and a communication interface.

[0016] In one embodiment, the sampler includes a filtering module, a digital-to-analog conversion module, a clock module, a power supply module, and a monitoring module sampler, and is composed of a radio frequency signal input port, an optical signal output port, a local oscillator input interface, a power supply interface, and a communication interface.

[0017] The above-mentioned high-precision multi-beam antenna for navigation is composed of a multi-beam antenna module, a multi-channel radio frequency module, and an anti-jamming digital module. The multi-beam antenna module is composed of a plurality of fixed-pointing narrow-beam units. Each beam has a stable phase center and sidelobe suppression ability, and each narrow-beam unit can independently receive signals. The signals received by all beams enter the anti-jamming digital module after being frequency-converted, filtered, and sampled by the multi-channel radio frequency module. The anti-jamming digital module assigns the reception weight of each signal according to the signal correlation result and flexibly switches between the beams, thereby completing the stable reception of the signals. This application comprehensively utilizes the characteristics of the antenna such as beam focusing, high phase stability, and low sidelobes, transforms the omnidirectional high-precision antenna into a multi-narrow-beam high-precision antenna, and realizes the anti-jamming function through beam switching based on the correlator, and finally realizes a high-precision monitoring receiving antenna with anti-jamming function, which can effectively solve the high-precision problem in the interference environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the principle of the high-precision multi-beam antenna for navigation in one embodiment;

[0019] Figure 2Schematic diagram of the structure of a multi-beam Luneburg lens antenna in an embodiment;

[0020] Figure 3 Schematic diagram of a low-noise amplifier module group in an embodiment;

[0021] Figure 4 Schematic diagram of a frequency converter in an embodiment;

[0022] Figure 5 Schematic diagram of a sampler in an embodiment;

[0023] Figure 6 Schematic diagram of an anti-interference digital module in an embodiment. Detailed implementation manners

[0024] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0025] In one embodiment, as Figure 1 shown, a navigation high-precision multi-beam antenna is provided, including:

[0026] A multi-beam antenna module, a multi-channel radio frequency module, and an anti-interference digital module; the multi-beam antenna module is composed of multiple narrow-beam antenna units with fixed directions, the narrow beams formed by each narrow-beam antenna unit are closely arranged, the beam coverage ranges overlap with each other, and jointly complete the beam coverage of the upper hemisphere, equivalently realizing an omnidirectional beam. Each single narrow-beam antenna unit integrates a filter, a limiter, and a low-noise amplifier, and has the functions of receiving signal limiting, low-noise amplification, and filtering; the multi-channel radio frequency module is composed of radio frequency channels with the same number as the narrow-beam antenna units, and the radio frequency channels are used to perform frequency conversion, filtering, and sampling on the beam reception signals output by the multi-beam antenna module; the anti-interference digital module is used to select the beam with the strongest signal relative to the interference according to the power and spatial distribution of the signal and the interference, so as to achieve the anti-interference function.

[0027] The above-mentioned navigation high-precision multi-beam antenna is composed of a multi-beam antenna module, a multi-channel radio frequency module, and an anti-jamming digital module. The multi-beam antenna module consists of multiple fixed-pointing narrow-beam units. Each beam has a stable phase center and sidelobe suppression ability, and each narrow-beam unit can receive signals independently. The signals received by all beams enter the anti-jamming digital module after being frequency-converted, filtered, and sampled by the multi-channel radio frequency module. The anti-jamming digital module assigns the reception weight of each signal according to the signal correlation result and flexibly switches between beams, thereby completing the stable reception of signals. This application comprehensively utilizes the characteristics of the antenna such as beam focusing, high phase stability, and low sidelobes, transforms the omnidirectional high-precision antenna into a multi-narrow-beam high-precision antenna, and realizes the anti-jamming function through beam switching based on a correlator, and finally realizes a high-precision monitoring receiving antenna with anti-jamming function, which can effectively solve the high-precision problem in an interference environment.

[0028] In one embodiment, the multi-beam antenna module is composed of multiple fixed-pointing narrow-beam antenna units. The narrow beams formed by each antenna unit are closely arranged, and the beam coverage ranges overlap with each other to jointly complete the beam coverage of the upper hemisphere, equivalently realizing an omnidirectional beam. The antenna unit realizes the reception of broadband signals in a fixed-pointing area, the operating frequency covers all satellite navigation frequency points, and the phase center is stable within the beam range, and the sidelobe level is low. A single antenna unit integrates a filter, a limiter, and a low-noise amplifier module, and has the functions of signal amplitude limiting, low-noise amplification, and filtering. The amplitude limiting function is used to limit the output amplitude under the condition that there is extremely strong power in the band. The amplification function is used to amplify the input signal to the target level without distortion. The filtering function is used to filter out-of-band interference signals.

[0029] In one embodiment, as Figure 2 shown, the multi-beam Luneburg lens antenna is composed of a spherical Luneburg lens and a feed array. The Luneburg lens has beam focusing ability, can realize narrow-beam high gain and sidelobe suppression performance, and at the same time, the highly rotationally symmetric spherical shape can ensure that the radiation characteristics are basically the same at all angles in the space domain. The feed array is composed of multiple identical broadband right-handed circularly polarized antenna units, which are placed at the surface focal position of the spherical Luneburg lens to realize multiple fixed-pointing narrow beams.

[0030] In another embodiment, the spherical Luneburg lens is composed of 4 layers of discrete dielectric spheres with different radii and dielectric constants. The first layer is a homogeneous dielectric sphere, and the ratio of its radius to the maximum radius is 0.53. The last three layers are designed according to the approximate equal-thickness layering method; and the dielectric constants of each layer are calculated according to the theoretical formula of the dielectric constant and radius of the Luneburg lens. The discrete dielectric lens is easy to implement in engineering, and by optimizing the radius and dielectric constant of each layer, the performance of the Luneburg lens similar to the continuous dielectric distribution can be realized.

[0031] In addition, the feed array consists of 34 broadband right-hand circularly polarized antenna elements, which are evenly distributed around the outside of the Luneburg lens and are divided into four layers in total. There is 1 antenna element in the first layer, 6 antenna elements in the second layer, 12 antenna elements in the third layer, and 15 antenna elements in the fourth layer. The included angle between the antenna elements of adjacent layers is the 3dB beam width after beam focusing, so as to ensure that the overlapping gain of adjacent beams only decreases by 3dB compared to the maximum gain, thereby ensuring that the antenna has stable and excellent gain performance within the required elevation angle range. The antenna elements within the layer are evenly distributed at the same rotation angle according to the antenna element size and the circumference, so as to ensure that the antenna beam can cover the entire azimuth angle. The feed array adjusts the distance from the outer surface of the Luneburg lens to ensure that the feed spacing is greater than 0.5 wavelengths, avoiding the influence of feed coupling on the radiation performance.

[0032] In one embodiment, the multi-beam antenna module further includes: a low-noise amplifier module group; the low-noise amplifier module group includes a plurality of independent low-noise amplifier modules, which are connected to the output ports of the multi-beam Luneburg lens antenna; the low-noise amplifier module includes a signal input port, a signal output port, and a power supply and monitoring interface. The low-noise amplifier module is internally composed of a limiting circuit, a pre-filtering circuit, a low-noise amplification circuit, a post-filtering circuit, and a power supply and monitoring circuit. The pre-filtering circuit, the limiting circuit, the low-noise amplification circuit, and the post-filtering circuit are connected in sequence. The pre-filtering circuit is connected to the signal input port, the post-filtering circuit is connected to the signal output port, and the power supply and monitoring circuit is connected to the power supply and monitoring interface.

[0033] In this embodiment, as Figure 3 shown, the low-noise amplifier module group includes a plurality of independent low-noise amplifier modules, which are connected to the output ports of the multi-beam Luneburg lens antenna. The signals received by the multi-beam Luneburg lens antenna first enter the limiting circuit inside the low-noise amplifier. The limiting circuit is mainly used to limit the signal amplitude output when there are strong interference signals in the received signal band, avoiding damage to the subsequent circuits by strong signals. After the signal passes through the limiting circuit, it is output to the pre-filtering circuit. The main function of this circuit is to filter out out-of-band interference signals with as low insertion loss as possible to ensure that the low-noise amplifier can work properly under interference conditions. After the signal passes through the pre-filtering circuit, it is output to the low-noise amplification circuit, which mainly amplifies the input signal with low noise to the target power. After the signal passes through the low-noise amplification circuit, it is output to the final filtering circuit, which mainly suppresses the out-of-band interference signals to below the target value. The inside of the low-noise amplifier module includes a power supply and monitoring circuit, which mainly converts the external power supply into the voltages required for the operation of each internal chip, and at the same time monitors the operating states of the low-noise amplifier such as voltage, current, and temperature. The modules communicate with each other using bus communication.

[0034] In one embodiment, the multi-channel radio frequency module consists of a plurality of independent radio frequency channels; each radio frequency channel includes: a frequency converter and a sampler.

[0035] Specifically, the isolation between channels is greater than 60 dB, and the group delay consistency is better than 0.2 ns. Considering the requirement of long-distance lossless signal transmission, the multi-channel RF module can also be configured with an optoelectronic converter, which has a flexible optoelectronic conversion function and can convert the sampled digital signal into an optical signal. The sampled signal can be transmitted over a long distance to the anti-interference digital module at the back end using an optical fiber.

[0036] In one embodiment, as Figure 4 shown, the frequency converter includes an input signal filtering module, a power adjustment module, a local oscillator module, a frequency conversion module, an output signal filtering module, a comprehensive control module, and a power supply module, and is composed of a signal input port, a signal output port, a local oscillator input interface, a power supply interface, and a communication interface.

[0037] Specifically, the frequency converter has frequency conversion and filtering functions. The frequency conversion function can select the application scenario to convert the received signal to a high frequency or an intermediate frequency, and the filtering function can select to switch different frequency point signals according to requirements to complete out-of-band interference suppression, local oscillator suppression, and image suppression.

[0038] Functionally, the externally input signal first passes through the input signal filtering module. The filtering module is composed of a radio frequency switch and a filter bank (composed of an A1 filter bank, an A2 filter bank, an A3 filter bank... an An filter bank). The filtering module switches different types of filtering modules under the control instruction to realize the filtering function of the input signal, filter out the out-of-band interference of the input signal, and realize the image suppression function to prevent the interference signal from affecting the normal operation of the subsequent circuit. After the signal passes through the input signal filtering module, it enters the power adjustment module. The power adjustment module is composed of an amplifier, a variable attenuator, and a power detection chip. The power adjustment module detects the power of the input signal, reports the detected power information, and adjusts the power of the input signal according to the external control instruction. After the signal passes through the power adjustment module, it enters the frequency conversion module. The frequency conversion module is mainly composed of a frequency converter and an external matching module. The frequency conversion module receives the local oscillator signal output by the local oscillator module and completes the frequency conversion function of the input signal in the frequency conversion module. After the signal passes through the frequency conversion module, it enters the output signal filtering module to realize the filtering function of the clutter signal of the frequency-converted signal, and the signal is output externally after filtering. The local oscillator module receives the externally input reference signal and generates the local oscillator signal required by the system according to the control information. The power supply module converts the external power supply into the voltages required for the operation of each internal chip. The comprehensive control module reports information such as the frequency conversion working state, such as the input signal power, the module attenuation value, the local oscillator frequency, and the filter module selection, to the outside, and converts the received external control information into the control parameters of each module inside the frequency converter.

[0039] In one embodiment, as Figure 5As shown, the sampler includes a filtering module, a digital-to-analog conversion module, a clock module, a power supply module, and an optoelectronic conversion module, and is composed of a radio frequency signal input port, an optical signal output port, a local oscillator input interface, a power supply interface, and a communication interface.

[0040] Specifically, the sampler includes filtering and sampling functions. The filtering function can select different frequency point signals as needed. The sampling function, with the assistance of a high-quality clock signal and a stable power supply, samples the radio frequency signal without distortion or aliasing by the digital-to-analog conversion module, and also has the function of detecting the current and temperature of the entire system to ensure the normal operation of the heat dissipation system. If the output of the frequency conversion module is a high-frequency signal, the sampler adopts a radio frequency sampling scheme; if the output of the frequency conversion module is an intermediate-frequency signal, the sampler adopts an intermediate-frequency sampling scheme.

[0041] Functionally, after the external input signal enters the sampler, it first passes through the filtering module. The filtering module consists of a radio frequency switch and a filter bank (B1 filter bank, B2 filter bank, B3 filter bank... Bn filter bank). The filtering module switches different types of filter modules under the control instruction to achieve the filtering function of the input signal and avoid the out-of-band clutter of the input signal causing distortion or aliasing of the sampling signal. The signal is output to the digital-to-analog conversion module after passing through the filter module. The digital-to-analog conversion module consists of a digital-to-analog conversion chip and its matching circuit. The module completes the sampling function of the input signal under the drive of an external sampling clock. After the radio frequency signal is sampled, it becomes a digital signal and is converted into an optical signal for external output after being processed in the optoelectronic conversion module. The clock generation module receives the external input reference signal and generates the sampling clock signal required by the system according to the control information. The power supply module converts the external power supply into the voltages required for the operation of each internal chip. The comprehensive control module reports the frequency conversion working state such as the input signal frequency, filter module selection information, sampling clock, current, and temperature to the outside, and converts the received external control information into the control parameters of each module inside the sampler.

[0042] As Figure 6 shown, the anti-jamming digital module selects the beam with the strongest signal relative to the interference according to the power and spatial distribution of the signal and the interference, captures it, and assigns it to the navigation receiver for tracking processing.

[0043] Specifically, the anti-jamming digital module mainly selects the beam with the strongest signal relative to the interference according to the power and spatial distribution of the signal and the interference, and assigns it to the navigation receiver for tracking processing. For the incident signal of a single satellite, the sampled signals of all N beams of the receiving antenna are first weighted by w. The signals of each beam are then correlated and accumulated in two paths, I and Q, with the local reference signal. Then, the correlation accumulation values of each beam are compared, and the beam with the largest accumulation value is selected as the beam for receiving the satellite signal. The weight value of this beam is set to 1, and the weight values of other beams are set to 0, so as to realize the selection of the optimal anti-jamming beam. The weighted acquisition information is finally transmitted to the navigation receiver for signal tracking and positioning solution processing.

[0044] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope recorded in this specification.

[0045] The above-described embodiments merely represent several implementation manners of the present application. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the invention. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several modifications and improvements can still be made, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the appended claims.

Claims

1. A navigation high-precision multi-beam antenna, characterized in that The multi-beam antenna includes: a multi-beam antenna module, a multi-channel radio frequency module, and an anti-jamming digital module; The multi-beam antenna module is composed of multiple narrow-beam antenna units with fixed pointing directions. The narrow beams formed by each narrow-beam antenna unit are closely arranged, and the beam coverage ranges overlap with each other to jointly complete the beam coverage of the upper hemisphere, equivalently realizing an omnidirectional beam. Each single narrow-beam antenna unit integrates a filter, a limiter, and a low-noise amplifier, and has the functions of limiting the received signal amplitude, low-noise amplification, and filtering; The multi-channel radio frequency module is composed of radio frequency channels with the same number as the narrow-beam antenna units. The radio frequency channels are used for frequency conversion, filtering, and sampling of the beam reception signals output by the multi-beam antenna module; The anti-jamming digital module is used to select the beam with the strongest signal relative to the interference for capture according to the power and spatial distribution of the signal and the interference, so as to realize the anti-jamming function; The multi-beam antenna module is implemented by a multi-beam Luneburg lens antenna and a low-noise amplifier module group; The multi-beam Luneburg lens antenna is composed of a spherical Luneburg lens and a feed array. The feed array is composed of multiple identical broadband right-hand circularly polarized antenna units, which are placed at the surface focal position of the spherical Luneburg lens to realize the characteristics of multiple narrow beams with fixed pointing directions.

2. The navigation high-precision multi-beam antenna according to claim 1, wherein The narrow-beam antenna unit realizes the reception of broadband signals in a fixed pointing area, and the operating frequency covers all satellite navigation frequency points. Moreover, the phase center is stable within the beam range, and the side lobe level is low. The limiter is used to limit the output amplitude under the condition of extremely strong power in the band; the low-noise amplifier is used to amplify the input signal to the target level without distortion; The filter is used to filter out-of-band interference signals.

3. The navigation high-precision multi-beam antenna according to claim 1, characterized in that The anti-jamming digital module selects the beam with the strongest signal relative to the interference for capture according to the power and spatial distribution of the signal and the interference, and assigns it to the navigation receiver for tracking processing; for the incident signal of a single satellite, the sampled signals of all N beams of the receiving antenna are first weighted by w. Then, the signals of each beam are correlated and accumulated in two paths, I and Q, with the local reference signal. Next, the correlation accumulation values of each beam are compared, and the beam with the largest accumulation value is selected as the beam for receiving the satellite signal, and the weight value of this beam is set to 1, and the weight values of other beams are set to 0, so as to realize the selection of the optimal anti-jamming beam. Finally, the weighted capture information is transmitted to the navigation receiver for signal tracking and positioning solution processing.

4. The navigation high-precision multi-beam antenna according to claim 1, characterized in that The spherical Luneburg lens is composed of 4 layers of discrete dielectric spheres with different radii and dielectric constants. The first layer is a homogeneous dielectric sphere, and the ratio of its radius to the maximum radius is 0.

53. The latter three layers are designed according to the approximate equal-thickness layering method; The feed array is composed of 34 broadband right-hand circularly polarized antenna units. The feed array is evenly distributed around the Luneburg lens and is divided into four layers in total. There is 1 antenna unit in the first layer, 6 antenna units in the second layer, 12 antenna units in the third layer, and 15 antenna units in the fourth layer; The included angle between the antenna units between layers is the 3dB beam width after beam focusing. The antenna units within a layer are evenly distributed at the same rotation angle according to the unit size and the circumference of the circle. The feed array adjusts the distance from the outer surface of the Luneburg lens to ensure that the feed spacing is greater than 0.5 wavelengths.

5. The navigation high-precision multi-beam antenna according to claim 1, characterized in that, The low-noise amplifier module group includes multiple independent low-noise amplifier modules, which are connected to the output ports of the multi-beam Luneburg lens antenna; each low-noise amplifier module includes a signal input port, a signal output port, and a power supply and monitoring interface. The interior of the low-noise amplifier module consists of a limiting circuit, a pre-filtering circuit, a low-noise amplification circuit, a post-filtering circuit, and a power supply and monitoring circuit. The pre-filtering circuit, the limiting circuit, the low-noise amplification circuit, and the post-filtering circuit are connected in sequence. The pre-filtering circuit is connected to the signal input port, the post-filtering circuit is connected to the signal output port, and the power supply and monitoring circuit is connected to the power supply and monitoring interface.

6. The navigation high-precision multi-beam antenna according to claim 1, characterized in that The multi-channel radio frequency module is composed of multiple independent radio frequency channels; Each of the radio frequency channels includes: a frequency converter and a sampler.

7. The navigation high-precision multi-beam antenna according to claim 6, characterized in that, The frequency converter includes an input signal filtering module, a power adjustment module, a local oscillator module, a frequency conversion module, an output signal filtering module, an integrated control module, and a power supply module, and is composed of a signal input port, a signal output port, a local oscillator input interface, a power supply interface, and a communication interface.

8. The navigation high-precision multi-beam antenna according to claim 6, characterized in that, The sampler includes a filtering module, a digital-to-analog conversion module, a clock module, a power supply module, and a monitoring module sampler, and is composed of a radio frequency signal input port, an optical signal output port, a local oscillator input interface, a power supply interface, and a communication interface.

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