Ray antenna array-based wireless communication system

Abstract

The invention discloses a wireless communication system based on a ray antenna array, which comprises the ray antenna array and a ray selection network, and is characterized in that the ray antenna array is formed by arranging a large number of low-cost antenna units according to a ray-shaped structure, and each ray corresponds to a'simple and uniform linear array 'and points to different orientations; all the antenna units are directly connected to the radio frequency combiner to serve as one path of signal output, so that each ray antenna array forms a wave beam matched with the orientation of the ray antenna array without depending on analog or digital wave beam forming. The ray selection network is composed of a radio frequency switch and is used for dynamically selecting a proper ray antenna array and connecting the ray antenna array to a radio frequency link for subsequent baseband processing. According to the invention, the hardware cost can be effectively reduced, the use of an expensive phase shifter is avoided, and the spatial resolution and the communication performance are improved at the same time, so that the problems of difficult realization and high cost of dynamic beams of millimeter wave, terahertz and other high-frequency wireless communication and sensing systems are solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of 6G and future wireless communication systems, and specifically relates to a low-cost, high-performance wireless communication system and method based on a ray antenna array. Background Art

[0002] The continuous advancement of MIMO (multiple-input multiple-output) technology has become the cornerstone of the evolution of wireless communication systems. To fully utilize spatial degrees of freedom, the size of antenna arrays continues to expand, significantly improving communication performance. The upcoming 6G mobile communication network is expected to provide high-performance communication, environmental perception, and positioning capabilities. Therefore, the further development of multi-antenna technology is crucial. Although the development paths of multi-antenna technology vary, the industry generally believes that the 6G era will adopt larger antenna arrays, higher frequency bands, and wider spectrums. However, simply increasing the system dimensions in the spatial and time / frequency domains will inevitably conflict with other 6G goals (such as improving energy efficiency and reducing costs). Therefore, it is crucial to develop advanced multi-antenna technology in a cost-effective manner without compromising or even improving performance.

[0003] RF links and front-end modules are typically the most expensive and energy-intensive components in wireless systems. Therefore, one effective way to reduce hardware and energy costs is to reduce the number of RF links or adopt more cost-effective RF components. To this end, analog beamforming and HBF (Hybrid Analog / Digital Beamforming) have been widely studied. In this approach, one or a few RF links are connected to a large number of antenna elements via a network of phase shifters. However, existing HBF architectures require a large number of expensive phase shifters, resulting in high system hardware costs. Designing high-precision phase shifters is particularly challenging in millimeter-wave and terahertz communications.

[0004] In order to reduce the hardware cost of the system, a variety of methods have been proposed, such as antenna subset selection methods, lens antennas, and new antenna architectures with reconfigurable antenna units (including fluid antennas and movable antennas). The antenna subset selection method replaces expensive phase shifters with RF switches, but this will result in performance degradation. The lens antenna array can focus the energy of the incident wave into a small area of the antenna array, thereby reducing hardware and energy costs. The new antenna architecture with reconfigurable antenna units is expected to significantly reduce the number of antenna units and their related RF components, but requires additional hardware costs, such as motors for controlling the movement of antenna units, which will result in additional energy consumption and longer response time. Therefore, a new multi-antenna architecture is needed that can reduce hardware costs while maintaining high communication performance. Summary of the Invention

[0005] The technical problem to be solved by the present invention is the difficulty and high cost in realizing dynamic beams in millimeter-wave and terahertz wireless communication and sensing systems. For this purpose, the present invention proposes a low-cost and high-performance wireless communication system based on a novel ray antenna array, including a novel ray antenna array and a ray selection network, which can effectively reduce the hardware cost, avoid the use of expensive phase shifters, and at the same time improve the spatial resolution and communication performance.

[0006] To solve the above technical problems, the present invention adopts the following technical solutions:

[0007] The present invention proposes a wireless communication system based on a ray antenna array, including: a ray antenna architecture formed by a plurality of ray antenna arrays arranged in a ray-like structure, and a ray selection network; wherein

[0008] Each ray antenna array is composed of a number of directional antenna units, and the spacing between adjacent antenna units is set to half wavelength; each ray antenna array is placed at an equal angular interval, and the angular interval between adjacent ray antenna arrays is set to the bandwidth from the peak point to the zero point of the main lobe of the beam pattern of the ray antenna array, so as to minimize the interference between adjacent ray antenna arrays and cover the required service range.

[0009] All the antenna units on each ray antenna array are respectively connected to a radio frequency combiner and then output as a single signal path, and this signal can coherently superpose in the direction of each ray antenna array to form a beam.

[0010] The ray selection network is composed of a plurality of radio frequency switches. The radio frequency combiner is connected to the radio frequency link through the radio frequency switch. During operation, based on the channel state information of the system, it dynamically selects the output signal of an appropriate ray antenna array and connects it to the radio frequency link for subsequent baseband signal processing. Specifically: the ray antenna architecture selects appropriate N signals from N signals through the ray selection network as the number of radio frequency links, where N < N; the selection matrix of the ray selection network is expressed as RF where N RF < N; the selection matrix of the ray selection network is expressed as which satisfies ||[S] i,: ||0 = 1 and ||[S] :,j ||0 ≤ 1, where 1 ≤ i ≤ N RF , 1 ≤ j ≤ N; then the selected N RF output ports are connected to the radio frequency link for further baseband signal processing.

[0011] Furthermore, in a wireless communication system based on a ray antenna array proposed in the present invention, the point where the extended lines of the rays of all ray antenna arrays intersect is assumed to be a reference origin. Then, the antenna unit of each ray antenna array closest to the reference origin must maintain a certain distance D from the reference origin to ensure that the minimum spacing between antenna units of adjacent ray antenna arrays is greater than half a wavelength, and M is the number of antenna units in the ray antenna array.

[0012] Furthermore, in the wireless communication system based on the ray antenna array proposed in the present invention, the steering vector on the n-th ray antenna array is modeled as:

[0013]

[0014] Among them, θ∈[-θ max ,θ max ] is the arrival angle, η n is the direction of the n-th ray antenna array, G(θ-η n ) is the radiation pattern of all antenna elements on the nth ray antenna array, characterized by peak radiation power and 3dB beamwidth, G(0) corresponds to the peak radiation power; λ is the signal wavelength, is the index set of the ray antenna array, n∈N; M is the number of antenna units in the ray antenna array.

[0015] According to the preset direction η of each ray antenna array n Place N ray antenna arrays, with the ray antenna array n=0 close to the central axis of the ray antenna structure as the reference ray antenna array, where the direction of the reference ray antenna array is the reference direction η n＝0 =0;

[0016] The combined output signal on the n-th ray antenna array is,

[0017]

[0018] in r(θ,η n ) is the beam pattern of the n-th ray antenna array, if and only if the ray antenna array is directed toward η n On the other hand, the signals can be coherently superimposed to form a beam.

[0019] The direction η of the n-th ray antenna array n for:

[0020]

[0021] The number N of ray antenna arrays is:

[0022]

[0023] The distance D between each ray antenna array needs to meet the following requirements:

[0024]

[0025] The radiation pattern of the antenna unit satisfies:

[0026]

[0027] Where ε is the preset threshold of the beam gain amplitude.

[0028] The present invention adopts the above technical solution, which has the following technical effects compared with the prior art:

[0029] This paper proposes a novel, cost-effective ray antenna array architecture for enhanced wireless communications that can form beams that match their orientation without relying on analog or digital beamforming. A ray selection network dynamically selects the appropriate ray antenna array and connects it to the RF link for subsequent baseband processing, offering the following advantages:

[0030] 1. Low hardware cost, eliminating the need for expensive phase shifters: Traditional HBF architectures rely on numerous expensive phase shifters. The ray antenna architecture of the present invention directly connects all antenna elements of each ray antenna array to an RF combiner as a single signal output. This allows each ray antenna array to form a beam that matches its orientation without relying on analog or digital beamforming, significantly reducing system cost. In millimeter-wave and terahertz communication and sensing systems, the cost of high-precision phase shifters is prohibitive. The ray antenna architecture significantly reduces hardware costs, making it suitable for massive MIMO systems.

[0031] 2. Higher spatial resolution and full spatial coverage: Due to its radial structure, the ray antenna architecture has uniform spatial resolution across all angular domains, providing even coverage across the entire space. Compared to the traditional uniform linear array beamforming based on the HBF architecture, the ray antenna architecture has higher spatial resolution at non-central angles (i.e., areas away from the main axis of the antenna array), effectively improving communication quality for edge users.

[0032] 3. Enhanced wireless communication performance: Because each ray antenna array only needs to cover a portion of the angular range, the antenna elements of a ray antenna array are more directional than traditional uniform linear arrays. This results in higher gain in specific directions, reduced beam sidelobe interference, and improved signal quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1This is a schematic diagram of the ray antenna array architecture proposed in the present invention. Explanation of the reference numbers in the figure: 1-ray antenna array; 2-antenna unit; 3-RF combiner; 4-ray selection network; 5-RF switch.

[0034] Figure 2 This is a schematic diagram of connecting the antenna units of a single-ray antenna array to a radio frequency combiner.

[0035] Figure 3 It is a schematic diagram of the radiation pattern of the antenna unit.

[0036] Figure 4 It is a schematic diagram of the beam pattern of the ray antenna array of the present invention and the traditional uniform linear array based on HBF. DETAILED DESCRIPTION

[0037] In order to better understand the purpose, structure and function of the present invention, the following is a further detailed description of a low-cost, high-performance wireless communication system and method based on a novel ray antenna array of the present invention in conjunction with the accompanying drawings.

[0038] The present invention provides a novel ray antenna array multi-antenna architecture, which includes multiple identical ray antenna arrays arranged in a ray-shaped structure and a ray selection network; all antenna units in each ray antenna array are directly connected to an RF combiner via RF lines to be combined into one signal output; the multi-channel combined output signal is connected to the ray selection network, and based on channel state information, the output signal of the appropriate ray antenna array is selected and connected to the RF link for baseband signal processing.

[0039] The ray antenna array is composed of multiple directional antenna units. Compared with traditional uniform linear array antenna units, the ray antenna array antenna units are more directional. The directional antenna units form a "simple uniform linear array" with a half-wavelength antenna spacing. The position of the first antenna unit on each ray antenna array is adjusted so that the spacing between the first antenna units of adjacent ray antenna arrays is greater than half a wavelength.

[0040] In the ray antenna architecture, ray antenna arrays are placed at equal angular intervals, and the angular intervals are set to the bandwidth from the peak point to the zero point of the main lobe of the beam pattern of the ray antenna array to minimize interference between adjacent ray antenna arrays.

[0041] All antenna units of each ray antenna array in the ray antenna architecture are directly connected to the RF combiner through RF lines, combined as one output signal, and connected to the ray selection network through RF lines.

[0042] The ray selection network consists of multiple RF switches, which dynamically select the appropriate ray antenna array output signal based on the system's channel state information and connect it to the RF link for baseband signal processing.

[0043] Figure 1 The schematic diagram of the ray antenna array architecture design is given. The ray antenna array architecture consists of NM directional antenna elements, and these antenna elements are arranged into N "simple uniform linear arrays". Each ray antenna array 1 contains M directional antenna elements 2, and the spacing between adjacent antenna elements is set to half wavelength, that is where λ is the signal wavelength. Assume that the intersection point of the extension lines of all rays is the reference origin, and the distance from the antenna element closest to the reference origin of each ray antenna array to the reference origin is D to ensure the minimum spacing between the antenna elements of adjacent ray antenna arrays.

[0044] Taking the ray antenna array near the central axis of the ray antenna architecture as the reference ray antenna array n = 0, the index set of all ray antenna arrays is thus Then the steering vector on the nth ray antenna array is modeled as

[0045]

[0046] where G(θ - η n ) is the radiation pattern of all antenna elements on the nth ray antenna array, characterized by the peak radiation power and 3dB beam width, and G(0) corresponds to the peak radiation power.

[0047] These N ray antenna arrays are arranged in a ray shape, and the N ray antenna arrays are placed according to the designed orientations η of each ray antenna array n where the orientation of the reference ray antenna array is taken as the reference direction η n＝0 = 0. All antenna elements of each ray antenna array are directly connected to the RF combiner 3 and output as one path of signal. Then the combined one-path output signal on the nth ray antenna array is

[0048]

[0049] r(θ, η n ) can be understood as the beam pattern of the nth ray antenna array. When and only when on the orientation η of the ray antenna array n , the signals can be coherently superimposed to form a beam without relying on analog or digital beamforming.

[0050] Then, based on the channel state information, the ray antenna architecture selects appropriate N RF signals from N signals through the ray selection network 4, where N RF is the number of RF links, and N RF < N. The selection matrix of the ray selection network is expressed as S ∈ which satisfies ||[S] i,:||0=1 and ||[S] :,j ||0≤1, where 1≤i≤N RF , 1≤j≤N. Then select N RF The output ports are connected to the RF link for subsequent baseband signal processing.

[0051] Figure 2 A specific schematic diagram of connecting all antenna units of each ray antenna array to the RF combiner is given, wherein all antenna units of each ray antenna array are connected to the RF combiner through RF lines as one output.

[0052] Based on the above definitions, the specific design steps for the orientation and distance D of each ray antenna array can be summarized as follows:

[0053] It can be observed that for the n-th ray antenna array, the maximum beam pattern is In order to obtain |r(θ,η n )| is maximum if and only if the angle θ = η n Can satisfy.

[0054] It can be observed that for the n-th ray antenna array, the minimum beam pattern is In order to obtain |r(θ,η n )|=0, if and only if the angle θ satisfies the following conditions

[0055]

[0056] From this, we can get any strip antenna array, the beam width from the peak to the zero point of the main lobe is

[0057]

[0058] Due to the nonlinear characteristics of the arcsin(·) function, it can be observed that |r(θ,η n )| is not evenly spaced, i.e. Therefore, for any n'≠n, the null point of the n'th ray antenna array cannot be perfectly aligned with the null point of the nth ray antenna array. To minimize interference between adjacent ray antenna arrays, the null point of the main lobe of a ray antenna array is aligned with the peak point of the main lobe of the adjacent ray antenna array.

[0059] Therefore, the orientation of each ray antenna array is designed to be

[0060]

[0061] The number of ray antenna arrays is designed to be

[0062]

[0063] In addition, to ensure that the distance between the first antenna elements of adjacent ray antenna arrays is greater than half a wavelength, the distance D needs to satisfy:

[0064]

[0065] The radiation pattern G(·) of the antenna element is designed to provide reliable beamforming performance over the entire arrival angle range. First, the effective beam gain at the arrival angle θ is defined as

[0066]

[0067] Therefore, the design principle of G(·) is to ensure that the effective gain is not lower than the preset threshold ε within the entire angle range, that is:

[0068]

[0069] Therefore, the radiation pattern G(·) of the antenna unit needs to satisfy

[0070]

[0071] The technical solution of the present invention is further described in detail below with reference to the accompanying drawings and embodiments:

[0072] The relevant parameters of this embodiment are: the number of antenna units in each ray antenna array is set to M=8, the maximum arrival angle is set to θ max = 0.5π, the number of ray antenna arrays is N = 13. The antenna unit radiation pattern adopts the 3GPP antenna model. Each antenna unit in the ray antenna architecture has a 3dB beamwidth of 0.3π to cover a narrow angular range, while the antenna units in the traditional uniform linear array based on the HBF architecture have a 3dB beamwidth of π to serve the entire angular range of arrival. Furthermore, the peak radiated power of the antenna units in the ray antenna architecture is set to 5.1335dB, while the peak radiated power of the traditional uniform linear array is set to 0dB to ensure the same radiated power.

[0073] Figure 3 It is a schematic diagram of the radiation pattern of the antenna unit of the new ray antenna array and the traditional uniform linear array based on HBF.

[0074] Figure 4 Figure 1 is a schematic diagram of the beam pattern of the proposed ray antenna array and the traditional uniform linear array based on HBF. Figure 4It can be observed that the ray antenna architecture can achieve efficient beamforming without relying on analog or digital beamforming, and the beam gain is significantly higher than that of the traditional uniform linear array based on HBF. In addition, the ray antenna architecture performs uniform sampling in the angular domain space and has a narrower main lobe beamwidth at non-center angles, which improves the spatial resolution and can achieve full spatial coverage.

[0075] Throughout this specification, references to terms such as "one embodiment," "example," or "specific example" indicate that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, schematic representations of these terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0076] The basic principles, main features, and advantages of the present invention are shown and described above. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are merely illustrative of the principles of the present invention. Various changes and modifications may be made to the present invention without departing from the spirit and scope of the present invention, and such changes and modifications fall within the scope of the invention as claimed.

Claims

1. A wireless communication system based on a ray antenna array, characterized in that: include: A ray antenna architecture formed by an array of multiple ray antennas arranged in a ray-like structure, and a ray selection network; in Each ray antenna array is composed of several antenna units. All antenna units on each ray antenna array are directly connected to the RF combiner and output as one signal. This signal can be coherently superimposed in the direction of each ray antenna array to form a beam. The ray selection network dynamically selects the output signal of the appropriate ray antenna array based on the system's channel state information and connects it to the RF link for subsequent baseband signal processing.

2. A wireless communication system based on a ray antenna array according to claim 1, characterized in that: The antenna unit is a directional antenna unit, and the spacing between adjacent antenna units in each ray antenna array is set to half a wavelength.

3. A wireless communication system based on a ray antenna array according to claim 1, characterized in that: Assume that the point where the extended lines of all ray antenna arrays intersect is the reference origin. Then, the antenna element closest to the reference origin in each ray antenna array must maintain a certain distance D from the reference origin to ensure that the minimum spacing between antenna elements of adjacent ray antenna arrays is not less than half a wavelength, where: Where λ is the signal wavelength and M is the number of antenna elements in the strip antenna array.

4. A wireless communication system based on a ray antenna array according to claim 1, characterized in that: Each ray antenna array is placed at equal angular intervals, and the angular interval between adjacent ray antenna arrays is set to the bandwidth from the peak point to the null point of the main lobe of the beam pattern of the ray antenna array to minimize interference between adjacent ray antenna arrays and cover the required service range.

5. A wireless communication system based on a ray antenna array according to claim 1, characterized in that: The number of rays N in the ray antenna array depends on the arrival angle range that needs to be covered, specifically: Among them, θ max represents the maximum range of the arrival angle, and M is the number of antenna elements in the ray antenna array.

6. A wireless communication system based on a ray antenna array according to claim 1, characterized in that: The ray selection network is composed of a multi-channel radio frequency switch, and the radio frequency combiner is connected to the radio frequency link through the radio frequency switch.

7. A wireless communication system based on a ray antenna array according to claim 1, characterized in that: The steering vector on the n-th ray antenna array is modeled as: Among them, θ∈[-θ max ,θ max ] is the arrival angle, η n is the direction of the n-th ray antenna array, G(θ-η n ) is the radiation pattern of all antenna elements on the nth ray antenna array, characterized by peak radiation power and 3dB beamwidth, G(0) corresponds to the peak radiation power; λ is the signal wavelength, is the index set of the ray antenna array, M is the number of antenna elements in the ray antenna array, and D is the distance from the first antenna element in each ray antenna array to the reference origin; According to the preset direction η of each ray antenna array n Place N ray antenna arrays, with the ray antenna array n=0 close to the central axis of the ray antenna structure as the reference ray antenna array, where the direction of the reference ray antenna array is the reference direction η n =0; The combined output signal on the n-th ray antenna array is, in r(θ,η n ) is the beam pattern of the n-th ray antenna array, if and only if the ray antenna array is directed toward η n On the other hand, the signals can be coherently superimposed to form a beam.

8. The wireless communication system based on a ray antenna array according to claim 1, characterized in that: Based on the channel state information, the ray antenna architecture selects appropriate N signals from N signals through the ray selection network. RF signals, the selection matrix of the ray selection network is expressed as: It satisfies ||[S] i,: ||0=1 and ||[S] :,j ||0≤1, Among them, N RF is the number of RF links, N RF <N;1≤i≤N RF , 1≤j≤N; Then select N RF The output ports are connected to the RF link for subsequent baseband signal processing.

9. A wireless communication system based on a ray antenna array according to any one of claims 1 or 7, characterized in that: The direction η of the n-th ray antenna array n for: in, represents the index set of the ray antenna array, N is the number of ray antenna arrays, and M is the number of antenna units in the ray antenna array.

10. A wireless communication system based on a ray antenna array according to any one of claims 1 or 2, characterized in that: The radiation pattern of the antenna unit satisfies: Where ε is the preset threshold of the beam gain amplitude.

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