A smart antenna system

Abstract

This utility model discloses an intelligent antenna system, including a multi-beam network, a power-division phase-shifting network, and a calibration network. The multi-beam network receives an RF signal at its input and its output is connected to the input of the power-division phase-shifting network. The output of the power-division phase-shifting network is connected to the input of the calibration network. The first output of the calibration network is connected to a radiation module, and its second output is connected to a controller. The controller can adjust the RF signal input to the multi-beam network based on the phase and / or amplitude of each channel fed back from the calibration network, so that the radiation module radiates an electromagnetic wave beam with a specific direction, shape, and gain. This structure allows for flexible extension from a one-dimensional multi-beam intelligent antenna system to a two-dimensional or even multi-dimensional multi-beam intelligent antenna system according to application requirements, not only increasing user capacity but also improving transmission efficiency and speed. It also enables real-time multi-beam control, better meeting the needs of different user scenarios.

Description

Technical Field

[0001] This utility model relates to the field of communication technology, and in particular to an intelligent antenna system. Background Technology

[0002] In the field of communication technology, smart antenna systems, as core devices for improving signal transmission efficiency and optimizing network coverage quality, are widely used in 5G / 6G mobile communication, satellite communication, and the Internet of Things (IoT). However, with the continuous growth in communication services' demands for bandwidth, speed, and multi-user access capabilities, traditional smart antenna systems are gradually revealing several technical bottlenecks, making it difficult to meet the performance requirements of complex application scenarios. Specific problems include: 1. Insufficient beam controllability and adaptability: Traditional smart antennas mostly rely on fixed beams or simple phase adjustment mechanisms, which can only cover signals in limited directions and cannot dynamically adjust the beam direction, shape, and gain according to user distribution and channel environment. For example, in dense urban mobile communication scenarios, user terminals are randomly distributed and there is multipath interference. Fixed beams are prone to signal coverage blind spots or overlapping areas, resulting in reduced communication speeds and increased packet loss rates for some users.

[0003] 2. Poor channel consistency and high risk of signal distortion: Smart antenna systems contain multiple signal transmission channels (such as feed networks and radiating elements), and traditional designs lack effective real-time calibration mechanisms. Affected by factors such as component fabrication errors, ambient temperature changes, and electromagnetic interference, the phase shift and amplitude attenuation of each channel vary significantly, leading to reduced beamforming accuracy and even beam shift and increased sidelobe levels, seriously affecting the stability and anti-interference capability of signal transmission.

[0004] 3. Limited System Integration and Scalability: Traditional smart antennas often implement multi-beam generation, power distribution, and phase adjustment functions through independent modules. The complex connections between modules not only increase system size and power consumption but also make it difficult to flexibly expand the number of beams or adjust radiation parameters according to application requirements. For example, in satellite communication, if it is necessary to increase the beam coverage area, multiple core modules need to be redesigned and replaced, which is costly and has a long adaptation period.

[0005] 4. Low energy efficiency and resource utilization: Due to the inability to precisely control the beam direction and coverage, traditional smart antennas waste a lot of energy during signal transmission (such as radiating signals into areas without users). At the same time, when multiple users share the same beam, resource competition is likely to occur, resulting in low overall system energy efficiency and resource utilization, making it difficult to meet the needs of the Internet of Things for low power consumption and wide connectivity of massive terminals.

[0006] In summary, there is an urgent need for a smart antenna system with real-time calibration capabilities, flexible beam control characteristics, and high integration to solve the aforementioned technical problems. Utility Model Content

[0007] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention proposes an intelligent antenna system.

[0008] The technical solution adopted by one embodiment of this utility model to solve its technical problem is: a smart antenna system, including a multi-beam network, a power-dividing phase-shifting network, and a calibration network; The input of the multi-beam network is fed with an RF signal, and the output is connected to the input of the power divider phase shifter network. The output of the power divider phase shifter network is connected to the input of the calibration network; The first output of the calibration network is connected to the radiation module, and the second output is connected to the controller. The controller can adjust the radio frequency signal input to the multi-beam network based on the phase and / or amplitude of each channel fed back by the calibration network, so that the radiation module radiates an electromagnetic wave beam with a specific direction, shape and gain.

[0009] As one of the preferred embodiments of this utility model, the radiation module includes 12 antenna arrays, the multi-beam network is set as an 8×8 Butler matrix, the power divider phase shifter network includes 4 hybrid couplers, the input ends of the 4 hybrid couplers are connected to the 4 output ends of the 8×8 Butler matrix, and the input ends of the 4 hybrid couplers and the other 4 output ends of the 8×8 Butler matrix are connected to the 12 antenna arrays one by one.

[0010] As one of the preferred embodiments of this utility model, the 8×8 Butler matrix includes 12 90° directional couplers, 4 67.5° phase shifters and 4 45° phase shifters; The twelve 90° directional couplers are arranged in three levels, with each level consisting of four 90° directional couplers. Four 67.5° phase shifters are connected one-to-one between the first-stage 90° directional coupler and the second-stage 90° directional coupler; Four 45° phase shifters are connected one-to-one between the second-stage 90° directional coupler and the third-stage 90° directional coupler; The first-stage 90° directional coupler is fed with an RF signal at its input, and the output of the third-stage 90° directional coupler is connected to the input of the power divider phase shifter network.

[0011] As one of the preferred embodiments of this utility model, the hybrid coupler is composed of microstrip lines, and the phases of the two output terminals of the hybrid coupler are θ1=0° and θ2=180°, respectively.

[0012] As one of the preferred embodiments of this utility model, the calibration network includes 12 couplers, 6 first 2×1 combiners, 3 second 2×1 combiners, and 1 3×1 combiner; The input terminals of the 12 couplers and 4 hybrid couplers, as well as the other 4 output terminals of the 8×8 Butler matrix, are connected one-to-one. The input terminals of the six first 2×1 combiners are connected one-to-one with the output terminals of the twelve couplers; The input terminals of the three second 2×1 combiners are connected one-to-one with the output terminals of the six first 2×1 combiners; The input terminal of the 3×1 combiner is connected to the output terminals of the three second 2×1 combiners in a one-to-one correspondence, and the output terminal of the 3×1 combiner is connected to the controller.

[0013] As one of the preferred embodiments of this utility model, the antenna array includes multiple dipole radiating elements.

[0014] The beneficial effects of this utility model are as follows: A smart antenna system includes a multi-beam network, a power-division phase-shifting network, and a calibration network; the input end of the multi-beam network is fed with a radio frequency signal, and its output end is connected to the input end of the power-division phase-shifting network; the output end of the power-division phase-shifting network is connected to the input end of the calibration network; the first output end of the calibration network is connected to the radiation module, and the second output end is connected to the controller; the controller can adjust the radio frequency signal input to the multi-beam network according to the phase and / or amplitude of each channel fed back by the calibration network, so that the radiation module radiates an electromagnetic wave beam with a specific direction, shape, and gain; through the above structure, the system can be flexibly extended from a one-dimensional multi-beam smart antenna system to a two-dimensional or even multi-dimensional multi-beam smart antenna system according to application requirements, which not only increases user capacity but also improves transmission efficiency and rate; at the same time, it also realizes real-time multi-beam control, better meeting the needs of different user scenarios. Attached Figure Description

[0015] The above and / or additional aspects and advantages of this utility model will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a topology diagram of a smart antenna system; Figure 2 To calibrate the network topology; Figure 3 A calibration flowchart for a smart antenna system; Figure 4 This is a multi-beam pattern of a smart antenna system. Detailed Implementation

[0016] This section will describe in detail the specific embodiments of the present utility model. The preferred embodiments of the present utility model are shown in the accompanying drawings. The purpose of the drawings is to supplement the textual description with graphics, so that people can intuitively and vividly understand each technical feature and the overall technical solution of the present utility model, but they should not be construed as limiting the scope of protection of the present utility model.

[0017] In the description of this utility model, "multiple" means two or more; "greater than," "less than," and "exceeding" are understood to exclude the stated number; "above," "below," and "within" are understood to include the stated number. The use of "first" and "second" in the description is merely for distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly specifying the number of indicated technical features or their sequential relationship.

[0018] In the description of this utility model, it should be understood that the directional descriptions, such as up, down, front, back, left, right, etc., indicate the directional or positional relationship based on the directional or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0019] In this utility model, unless otherwise explicitly defined, the terms "setting," "installing," and "connecting" should be interpreted broadly. For example, they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to a fixed connection, a detachable connection, or an integral molding; they can refer to a mechanical connection; they can refer to the internal connection of two components or the interaction between two components. Those skilled in the art can reasonably determine the specific meaning of the above terms in this utility model in conjunction with the specific content of the technical solution.

[0020] Reference Figures 1-4 A smart antenna system includes a multi-beam network 10, a power-dividing phase-shifting network 20, and a calibration network 30; The input of the multi-beam network 10 is fed with an RF signal, and its output is connected to the input of the power divider phase shifter network 20. The output of the power divider phase shifter network 20 is connected to the input of the calibration network 30; The first output terminal of the calibration network 30 is connected to the radiation module 40, and the second output terminal is connected to the controller. The controller can adjust the radio frequency signal input to the multi-beam network 10 according to the phase and / or amplitude of each channel fed back by the calibration network 30, so that the radiation module 40 radiates an electromagnetic wave beam with a specific direction, shape and gain.

[0021] Reference Figure 1-3In this invention, the multi-beam network 10 is implemented by cascading multiple stages of couplers and phase shifters. By adjusting the phase characteristics of the phase shifters, the phase distribution of a set of outputs corresponding to each input can be achieved, and the phase difference of each set of outputs among multiple inputs is symmetrically and equally distributed. The input of the power-dividing phase-shifting network 20 is electrically connected to the output of the multi-beam network 10. By adjusting the amplitude distribution of the power-dividing phase-shifting network 20, N-end input and M-end output can be achieved, where M>N. The amplitude distribution of the output can meet the requirements of uniform distribution, normal distribution, Chebyshev distribution, or Taylor distribution, etc. The output of the power-dividing phase-shifting network 20 is electrically connected to the radiation module 40. The calibration network 30 is composed of a multi-stage cascaded coupling network, wherein the output of each power-dividing phase-shifting network 20 is connected to the radiation module 40. All branches electrically connected to module 40 need to be coupled to the corresponding couplers of calibration network 40, and the couplers corresponding to each branch need to be aggregated to the total port of calibration network through multi-stage combiners. Furthermore, the specific implementation structures of multi-beam network 10, power divider phase shifter network 20, and calibration network 30 can be any one of microstrip line, substrate integrated waveguide (SIW), stripline, coplanar waveguide (CPW), polygonal waveguide, or curved frame waveguide. The amplitude and phase characteristics fed to radiation module 40 can be monitored in real time through calibration network 40, and real-time calibration can be achieved by adjusting the phase of phase shifter of multi-beam network 10 to meet the needs of different application scenarios. It can be flexibly extended from one-dimensional multi-beam smart antenna system to two-dimensional or even multi-dimensional multi-beam smart antenna system according to application requirements.

[0022] Reference Figure 3 This invention utilizes a calibration network 40 to initialize and calibrate the smart antenna system, ensuring that the performance parameters of each channel, such as phase and amplitude, are in a reference and accurate state in the initial state. Through relevant detection and calculation methods, the differences in phase, amplitude, etc., between each channel are determined. During this process, the signal distribution and phase shift characteristics of each channel of the power divider / phase shifter network 20 are detected to obtain specific data on channel differences. Based on the calculated channel difference data, beamforming is optimized and improved. The power divider / phase shifter network 20 adjusts the power distribution and phase shift of the signal according to the difference, so that the radiation module 40 can radiate an electromagnetic wave beam with a specific direction, shape, and gain according to the optimized parameters, thereby realizing the functions of directional and efficient signal coverage or reception of the smart antenna. The antenna system is periodically monitored to continuously detect the working status of the smart antenna and the performance changes of each channel. When new changes are found in the channel differences, the system returns to the channel difference calculation stage and repeats the above calculation and beamforming improvement process to ensure that the smart antenna always maintains good working performance and adapts to the constantly changing working environment and requirements.

[0023] Reference Figures 1-3In a preferred embodiment of the smart antenna system provided by this utility model, the radiation module 40 includes 12 antenna arrays 41, the multi-beam network 10 is configured as an 8×8 Butler matrix, and the power-dividing phase-shifting network 20 includes 4 hybrid couplers 21. The input ends of the 4 hybrid couplers 21 are connected to the 4 output ends of the 8×8 Butler matrix, and the input ends of the 4 hybrid couplers 21 and the other 4 output ends of the 8×8 Butler matrix are connected one-to-one with the 12 antenna arrays 41. Specifically, the multi-beam network 10 is composed of one 8×8 Butler matrix, that is, the multi-beam network 10 has 8 input ends and 8 output ends. The hybrid couplers 21 have 1 input end and 2 output ends. The input ends of the 4 hybrid couplers 21 are connected one-to-one with the 4 output ends of the 8×8 Butler matrix, thereby expanding the 8 output ends of the 8×8 Butler matrix into 12 output ends, which are then connected one-to-one with the 12 antenna arrays 41 of the radiation module 40.

[0024] Reference Figure 1 In some embodiments, the 8×8 Butler matrix includes 12 90° directional couplers 31, 4 67.5° phase shifters 12, and 4 45° phase shifters 13; the 12 90° directional couplers 31 are arranged in 3 stages, with each stage including 4 90° directional couplers 31; the 4 67.5° phase shifters 12 are connected one-to-one between the first-stage 90° directional couplers 31 and the second-stage 90° directional couplers 31; the 4 45° phase shifters 13 are connected one-to-one between the second-stage 90° directional couplers 31 and the third-stage 90° directional couplers 31; the input terminal of the first-stage 90° directional coupler 31 is fed with an RF signal, and the output terminal of the third-stage 90° directional coupler 31 is connected to the input terminal of the power divider phase shifter network 20.

[0025] In a further embodiment, the hybrid coupler 21 is composed of microstrip lines, and the power-dividing phase-shifting network 20 uses an unbalanced hybrid coupler. The power output to ports A1-A12 of the radiating module 40 is shown in the table below:

[0026] Reference Figures 1-2In some embodiments, the calibration network 30 includes 12 couplers 31, 6 first 2×1 combiners 32, 3 second 2×1 combiners 33, and 1 3×1 combiner 34; the 12 couplers 31 are connected one-to-one with the inputs of the 4 hybrid couplers 21 and the other 4 outputs of the 8×8 Butler matrix; the inputs of the 6 first 2×1 combiners 32 are connected one-to-one with the outputs of the 12 couplers 31; the inputs of the 3 second 2×1 combiners 33 are connected one-to-one with the outputs of the 6 first 2×1 combiners 32; the inputs of the 3×1 combiner 34 are connected one-to-one with the outputs of the 3 second 2×1 combiners 33, and the output of the 3×1 combiner 34 is connected to the controller.

[0027] Specifically, antenna array 41 includes multiple dipole radiating elements, and radio frequency signals are input from the input terminals P1-P8 of the 8×8 Butler matrix, respectively. The phases of the 12 antenna arrays 41 (A1-A12) are shown in the table below:

[0028] The specific working principle of this utility model is as follows: The Butler matrix, as a passive feed network, typically manifests as an N-port input, N-port output analog beamforming network. Each input port is impedance matched and isolated. When excitation is applied to one port, the signals at the N output ports have equal amplitude and a constant phase difference Δφ. For the k-th input port (k=1, 2, ..., N) being excited, the phase difference Δφk between the output ports is given by:

[0029] Therefore, by switching different input ports, different phase differences Δφk can be generated at the output ports, and the number of input ports N is the number of output port phase differences Δφk. For an N×N Butler matrix, the phases of its output ports are 0, Δφk, 2Δφk, ..., (N-1)Δφk, respectively. To expand the number of N output ports of the Butler matrix and achieve arbitrary output power ratios, a power-dividing phase-shifting network is introduced. For a hybrid coupler, phases θ1 and θ2 are introduced at its two output ports, respectively, which can divide the signals with different outputs after passing through the hybrid coupler into two categories, represented by φ. z1 and φ z2 express:

[0030] Here is a set of solutions for the phases θ1 and θ2 obtained from solving the equation: θ1 = 0° and θ2 = 180°. Through the well-designed power divider phase shifter network 20, the phase difference Δφk at the input port of the radiation module 40 can change with different input ports, thereby affecting the beam deflection angle of the radiation element and achieving multi-beamforming. The final scanning angle θ of the radiation module 40 is... A The following conditions must be met:

[0031] Where d is the spacing between radiating elements.

[0032] The technical effects of this utility model will be further explained below with reference to simulation experiments: 1. Experimental conditions and contents The unequal power distribution multibeam network 10 was simulated using the simulation software HFSS, with the simulation element conditions set as radiation boundary conditions.

[0033] 2. Analysis of Experimental Results Reference Figure 4 L1, L2, L3, R1, R2, and R3 are the beams generated by the multi-beam network 10 when it is excited at ports P1-P6, respectively. Figure 4 In the diagram, the radial length represents the antenna gain (in dBi), and the polar angle Φ represents the antenna azimuth angle, ranging from 0 to 360°. Simulation results show that the designed unequal power distribution multi-beam network 10 can achieve the goal of multi-beaming, and due to the adjusted port power distribution, it achieves a suppression level of more than 20dB for sidelobe levels. The above simulation examples illustrate that the unequal power distribution multi-beam network 10 of this invention can make the amplitude of the output port present an arbitrary proportional distribution, and the phase present an equal arithmetic distribution, thus achieving the goal of multi-beamforming.

[0034] Of course, this utility model is not limited to the above-described embodiments. Those skilled in the art can make equivalent modifications or substitutions without departing from the spirit of this utility model. All such equivalent modifications and substitutions are included within the scope defined by the claims of this application.

Claims

1. A smart antenna system, characterized in that: It includes a multi-beam network (10), a power-dividing phase-shifting network (20), and a calibration network (30); The input end of the multi-beam network (10) is fed with a radio frequency signal, and the output end is connected to the input end of the power divider phase shifter network (20). The output of the power divider phase shifter network (20) is connected to the input of the calibration network (30); The first output of the calibration network (30) is connected to the radiation module (40), and the second output is connected to the controller; The controller can adjust the radio frequency signal input to the multi-beam network (10) according to the phase and / or amplitude of each channel fed back by the calibration network (30) so that the radiation module (40) radiates an electromagnetic wave beam with a specific direction, shape and gain.

2. The smart antenna system according to claim 1, characterized in that: The radiation module (40) includes 12 antenna arrays (41), the multi-beam network (10) is configured as an 8×8 Butler matrix, the power-division phase-shifting network (20) includes 4 hybrid couplers (21), the input terminals of the 4 hybrid couplers (21) are connected to the 4 output terminals of the 8×8 Butler matrix, and the input terminals of the 4 hybrid couplers (21) and the other 4 output terminals of the 8×8 Butler matrix are connected to the 12 antenna arrays (41) one by one.

3. The smart antenna system according to claim 2, characterized in that: The 8×8 Butler matrix includes 12 90° directional couplers (11), 4 67.5° phase shifters (12) and 4 45° phase shifters (13). The 12 90° directional couplers (11) are arranged in 3 levels, with each level including 4 of the 90° directional couplers (11). The four 67.5° phase shifters (12) are connected one-to-one between the first-stage 90° directional coupler (11) and the second-stage 90° directional coupler (11); The four 45° phase shifters (13) are connected one-to-one between the second-stage 90° directional coupler (11) and the third-stage 90° directional coupler (11); The first-stage 90° directional coupler (11) is fed with an RF signal at its input terminal, and the third-stage 90° directional coupler (11) is connected to the input terminal of the power divider phase shifter network (20).

4. The smart antenna system according to claim 2, characterized in that: The hybrid coupler (21) is composed of microstrip lines, and the phases of the two output terminals of the hybrid coupler (21) are θ1=0° and θ2=180°, respectively.

5. The smart antenna system according to claim 2, characterized in that: The calibration network (30) includes 12 couplers (31), 6 first 2×1 combiners (32), 3 second 2×1 combiners (33) and 1 3×1 combiner (34). The input terminals of the 12 couplers (31) and the 4 hybrid couplers (21) are connected one-to-one with the other 4 output terminals of the 8×8 Butler matrix; The input terminals of the six first 2×1 combiners (32) are connected one-to-one with the output terminals of the twelve couplers (31); The input terminals of the three second 2×1 combiners (33) are connected one-to-one with the output terminals of the six first 2×1 combiners (32); The input terminal of the 3×1 combiner (34) is connected to the output terminals of the three second 2×1 combiners (33) in a one-to-one correspondence, and the output terminal of the 3×1 combiner (34) is connected to the controller.

6. The smart antenna system according to claim 2, characterized in that: The antenna array (41) includes multiple dipole radiating elements.

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