A 1-bit electrically controlled two-dimensional beam scanning circularly polarized antenna

Abstract

This invention discloses a 1-bit electrically controlled two-dimensional beam-scanning circularly polarized antenna, relating to the field of antenna technology. Firstly, phase compensation is used to suppress the symmetrical beam caused by 1-bit phase quantization using a 1-bit phase shifter, ensuring the singleness and directional clarity of the main beam during scanning, thereby reducing the array's sidelobe level and enhancing anti-interference capability. Then, four circularly polarized elements are sequentially rotated at 0°, 90°, 180°, and 270° to form a circularly polarized antenna subarray. During beamforming, the phase difference generated by the sequential rotation of the main polarized electromagnetic wave of the circularly polarized array is compensated by the 1-bit phase shifter and phase compensation structure. The phase difference of the cross-polarized electromagnetic waves cannot be effectively compensated, resulting in mutual cancellation, thus reducing the antenna's axial ratio. This effectively suppresses multipath interference and Faraday's electromagnetic rotation effect while enhancing anti-interference capability, significantly improving signal quality for high-quality communication.

Description

Technical Field

[0001] This invention relates to the field of antenna technology, and in particular to a 1-bit electrically controlled two-dimensional beam scanning circularly polarized antenna. Background Technology

[0002] With the increasing complexity of communication and monitoring systems, the demand for antennas with beam scanning capabilities is becoming more and more urgent. At present, the mainstream technologies for achieving beam scanning include mechanically scanned antennas, phased array antennas, reflective / transmittance array antennas, fixed-frequency beam-scanning leaky antennas, and linearly polarized N-bit phase quantization array antennas.

[0003] Mechanically rotating antennas, including reflector antennas and array antennas, achieve beam scanning by mechanically rotating the radiating aperture. However, their scanning speed is slow and their pointing accuracy is limited by the precision of mechanical control. Phased array antennas use electronic control to adjust the phase of the array elements to achieve beam scanning, but they require the integration of a large number of T / R (transmit / receive) components, resulting in high system cost, complex feeding network, high profile, and large overall size, weight, and power consumption. Reflector array and transmission array antennas can achieve beam scanning through reconfigurable elements, but they usually require horn for spatial feeding, resulting in a high antenna profile.

[0004] Based on the problems existing in mechanically scanned antennas, phased array antennas, and reflective / transmittance array antennas, fixed-frequency beam-scanning leaky-wave antennas can achieve scanning through N-bit amplitude or phase control, but their transmission structure has dispersion characteristics, which easily causes beam squinting. Linearly polarized N-bit phase quantization array antennas can solve the problems existing in fixed-frequency beam-scanning leaky-wave antennas by loading switching devices in the radiating element or feeding structure to provide multi-bit phase states. However, linearly polarized N-bit phase quantization array antennas rely on loading switching devices to achieve multi-bit phase states, and they are susceptible to multipath interference and Faraday rotation effects in complex channel environments, resulting in significant signal attenuation and difficulty in achieving high-quality communication. Summary of the Invention

[0005] This invention provides a 1-bit electrically controlled two-dimensional beam scanning circularly polarized antenna, which can solve the problems existing in the prior art.

[0006] This invention provides a 1-bit electrically controlled two-dimensional beam scanning circularly polarized antenna, including a circularly polarized antenna array, a phase compensation structure, a 1-bit phase shifter, and a power divider network; The power divider network is a two-dimensional planar power divider network composed of cascaded power divider structures, and includes multiple output terminals for receiving electromagnetic waves and distributing the electromagnetic waves into multiple outputs from the multiple output terminals. Multiple 1-bit phase shifters are disposed on the top surface of the power divider network, and each output of the power divider network is connected to the input of a 1-bit phase shifter. Each 1-bit phase shifter is used to switch the phase of an electromagnetic wave by 0° or 180°. The input terminals of the multiple phase compensation structures are sequentially connected to the output terminals of multiple 1-bit phase shifters for phase compensation of multiple electromagnetic waves after phase switching. The circularly polarized antenna array consists of multiple arrays of circularly polarized antenna subarrays arranged on the surfaces of multiple phase compensation structures. Each circularly polarized antenna subarray includes circularly polarized elements arranged in sequence at 0°, 90°, 180°, and 270°. The output of each phase compensation structure feeds electromagnetic waves into the circularly polarized elements one-to-one through the feed point of the circularly polarized elements. During beamforming, the phase difference generated by the sequential rotation of the main polarized electromagnetic wave through the four circularly polarized elements arranged in sequence at 0°, 90°, 180°, and 270° within the same circularly polarized antenna subarray is compensated by a 1-bit phase shifter and the phase compensation structure. The phase difference of cross-polarized elements is not compensated and cancels each other out, so as to synthesize a circularly polarized radiation field on the array aperture surface for scattering.

[0007] Preferably, it also includes a beam control module; The beam control module is connected to the bias circuit of the 1-bit phase shifter, and controls the bias state of the bias circuit to switch the phase of the electromagnetic wave signal between 0° and 180°.

[0008] Preferably, the circularly polarized antenna subarray comprises 2×2 circularly polarized elements; The 2×2 circularly polarized elements in the circularly polarized antenna subarray are arranged in a clockwise rotation of 0°, 90°, 180°, and 270°, or in a counterclockwise rotation of 0°, 90°, 180°, and 270°, respectively. The circularly polarized antenna array can also be composed of M×N circularly polarized units arranged in a sequential rotation, wherein the rotation angle of the circularly polarized unit located in the Mth row and Nth column of the circularly polarized antenna array is (M+N)×90°, where M and N are positive integers.

[0009] Preferably, the circular polarization unit adopts a single-feed, dual-feed, or multi-feed single-layer or multi-layer radiating patch structure.

[0010] Preferably, the power divider network is any number of cascaded 1-power dividers or 2-power dividers; The power divider network is a transmission line structure, employing rectangular waveguides, ridge waveguides, circular waveguides, parallel plate waveguides, gap waveguides, substrate integrated waveguides, dielectric waveguides, microstrip transmission lines, striplines, coplanar waveguides, or slot lines. The power divider network is fed using parallel feeding, series feeding, reflector feeding, lens feeding, or multi-channel independent signal feeding structures. Substrate-integrated coaxial lines, printed ridge gap waveguides, substrate-integrated waveguides, dielectric waveguides, microstrip transmission lines, striplines, coplanar waveguides, or slot lines are also used.

[0011] Preferably, the phase compensation structure adopts a substrate integrated coaxial line, a printed ridge gap waveguide, a substrate integrated waveguide, a dielectric waveguide, a microstrip transmission line, a stripline, a coplanar waveguide, or a slot line.

[0012] Preferably, the 1-bit phase shifter includes a phase shifting structure and a bias circuit; The phase-shifting structure adopts a self-switching line structure, a loaded line structure, a high-pass-low-pass structure, or a reflective phase-shifting structure; The bias circuit includes a metal patch, metal vias, and active electronic components for adjusting the operating state of the 1-bit phase shifter; the active electronic components are PIN diodes, varactor diodes, or MEMS switches.

[0013] Preferably, the circularly polarized antenna array is arranged by sequentially rotating the circularly polarized elements or by sequentially rotating the circularly polarized antenna subarrays.

[0014] This invention provides a 1-bit electrically controlled two-dimensional beam-scanning circularly polarized antenna, which has the following advantages compared with the prior art: The power divider network in this invention distributes electromagnetic waves into multiple outputs. Each output electromagnetic wave signal undergoes a 1-bit phase shifter for 0° or 180° phase switching. Simultaneously, the phase-switched electromagnetic wave signal is phase-compensated by a phase compensation structure. This process suppresses the symmetrical beam caused by 1-bit phase quantization by the 1-bit phase shifter, ensuring the singleness and directional accuracy of the main beam during scanning, thereby reducing the array's sidelobe level and enhancing anti-interference capabilities. Then, the four circular polarization units are... A circularly polarized antenna subarray is formed by rotating the subarrays at 0°, 90°, 180°, and 270°. When multiple circularly polarized antenna subarrays are arranged, the phase difference generated by the sequential rotation of the main polarized electromagnetic wave through the 2×2 circularly polarized units during beamforming is compensated by a 1-bit phase shifter and a phase compensation structure. However, the phase difference of the cross-polarized subarrays cannot be effectively compensated, resulting in mutual cancellation. This reduces the axial ratio of the antenna, thereby effectively suppressing multipath interference and Faraday's electromagnetic rotation effect while enhancing anti-interference capability, and significantly improving signal quality for high-quality communication. Attached Figure Description

[0015] Figure 1 A side view schematic diagram of the principle architecture of a 1-bit electrically controlled two-dimensional beam scanning circularly polarized antenna provided in an embodiment of the present invention; Figure 2 A top view schematic diagram of the principle architecture of a 1-bit electrically controlled two-dimensional beam scanning circularly polarized antenna provided in an embodiment of the present invention; Figure 3 A schematic diagram of a uniformly arranged circularly polarized antenna array that feeds two circularly polarized antenna elements using a 1-bit electronically controlled two-dimensional beam scanning circularly polarized antenna, provided as an embodiment of the present invention; Figure 4 A schematic diagram of a uniformly arranged circularly polarized antenna array that feeds two circularly polarized antenna elements using another 1-bit phase shifter and phase compensation structure for a 1-bit electrically controlled two-dimensional beam scanning circularly polarized antenna provided in an embodiment of the present invention. Figure 5 This is a schematic diagram of the first form of a 1-bit circularly polarized antenna array for a 1-bit electrically controlled two-dimensional beam scanning circularly polarized antenna provided in an embodiment of the present invention, wherein 2×2 elements are rotated clockwise by 0°, 90°, 180° and 270° in sequence to form a sequential rotating array; Figure 6 This is a schematic diagram of a second form of a 1-bit circularly polarized antenna array for a 1-bit electrically controlled two-dimensional beam scanning circularly polarized antenna provided in an embodiment of the present invention, wherein 2×2 elements are rotated counterclockwise by 0°, 90°, 180° and 270° in sequence to form a sequential rotating array; Figure 7 This is a schematic diagram of the third form of a 1-bit circularly polarized antenna array for a 1-bit electrically controlled two-dimensional beam scanning circularly polarized antenna provided in an embodiment of the present invention. In this array, all elements are rotated sequentially by (m+n)×90° to form a sequential rotating array, where m and n represent the positions of the elements in the M×N array. Figure 8 The schematic diagram of a 44-scale 1-bit circularly polarized antenna array for a 1-bit electrically controlled two-dimensional beam scanning circularly polarized antenna provided in an embodiment of the present invention is shown, wherein 2×2 elements are rotated clockwise by 0°, 90°, 180° and 270° in sequence to form a sequential rotating array; Figure 9 The schematic diagram of a 1-bit circularly polarized antenna array with a scale of 1616 is provided for an embodiment of the present invention, wherein 2×2 elements are rotated clockwise by 0°, 90°, 180° and 270° in sequence to form a sequential rotating array. Figure 10 This is a schematic diagram of the first type of 1-bit circularly polarized antenna unit structure for a 1-bit electrically controlled two-dimensional beam scanning circularly polarized antenna provided in an embodiment of the present invention, including a 1-bit phase shifter, a phase compensation structure and a circularly polarized antenna unit; Figure 11 This invention provides a second 1-bit circularly polarized antenna element structure for a 1-bit electrically controlled two-dimensional beam scanning circularly polarized antenna, and a schematic diagram showing the types of circularly polarized antenna elements that can be selected. Figure 12 This invention provides a phase compensation structure for a 1-bit electrically controlled two-dimensional beam scanning circularly polarized antenna, and a schematic diagram showing the types of phase compensation structures that can be selected. Figure 13 This invention provides a 1-bit electrically controlled two-dimensional beam scanning circularly polarized antenna with a 1-bit circularly polarized antenna selection phase shifter structure, and a schematic diagram of the types of phase shifters that can be selected. Figure 14 This is a schematic diagram of a power divider network in parallel feeding form for a 1-bit electrically controlled two-dimensional beam scanning circularly polarized antenna, provided as an embodiment of the present invention. Figure 15 This is a schematic diagram of a power divider network in the series feeding form of a 1-bit electrically controlled two-dimensional beam scanning circularly polarized antenna provided in an embodiment of the present invention; Figure 16 This is a schematic diagram of a power divider network for the reflector feeding form of a 1-bit electrically controlled two-dimensional beam scanning circularly polarized antenna, provided in an embodiment of the present invention. Figure 17 This is a schematic diagram of a lens-feed power divider network for a 1-bit electrically controlled two-dimensional beam scanning circularly polarized antenna, provided in an embodiment of the present invention. Figure 18 This invention provides a schematic diagram of a power divider network for a multi-channel independent signal feeding configuration of a 1-bit electrically controlled two-dimensional beam scanning circularly polarized antenna. Figure 19 This is a schematic diagram of the beam scanning result of a 1-bit electrically controlled two-dimensional beam scanning circularly polarized antenna provided in an embodiment of the present invention; The components include: 1. Circularly polarized antenna array, 2. Phase compensation structure, 3. 1-bit phase shifter, 4. Power divider network, and 5. Beam control module. Detailed Implementation

[0016] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0017] With the increasing complexity of communication and monitoring systems, the demand for antennas with beam scanning capabilities is becoming more urgent; however, existing beam scanning antenna technologies all have limitations to varying degrees, making it difficult to achieve a good balance between cost, performance, size, and power consumption. (1) Mechanical rotating antenna (including reflector antenna and array antenna): beam scanning is achieved by mechanically rotating the radiating aperture. However, it has the problems of slow scanning speed and pointing accuracy being limited by mechanical control precision.

[0018] (2) Phased array antenna: The phase of the array unit is adjusted by electronic control to achieve beam scanning, but a large number of T / R (transmit / receive) components need to be integrated, resulting in high system cost, complex power supply network, high profile, and large overall size, weight and power consumption.

[0019] (3) Reflection array and transmission array antennas: Although beam scanning can be achieved through reconfigurable elements, they usually require horn for spatial feeding, resulting in a high antenna profile; in addition, both have edge overflow loss, which affects the overall efficiency.

[0020] (4) Fixed-frequency beam scanning leaky antenna: scanning can be achieved through N-bit amplitude or phase control, but its transmission structure has dispersion characteristics, which can easily cause beam squint.

[0021] (5) Linearly polarized N-bit phase quantization array: Switching devices are loaded in the radiating unit or feeding structure to provide multi-bit phase states, but its linear polarization characteristics are not strong enough to resist multipath interference and Faraday rotation effect.

[0022] In summary, existing beam-scanning antennas often have significant shortcomings in terms of cost, profile, loss, beam quality, or polarization performance when implementing electronically controlled scanning. There is an urgent need for an antenna solution that combines low complexity, low cost, low profile, low power consumption, and good circularly polarized beam-scanning performance. Based on this, the present invention provides a 1-bit electronically controlled two-dimensional beam-scanning circularly polarized antenna. The power divider network transmits electromagnetic power to a 1-bit phase shifter, which is connected to a phase compensation device. The electromagnetic power, after 1-bit phase switching and specific phase compensation, radiates a circularly polarized electromagnetic beam into free space through a circularly polarized antenna array. The 1-bit phase shifter incorporates electronic switching elements, whose bias state is controlled by a bias voltage signal provided by the beam control module, thereby achieving electronically controlled two-dimensional beam scanning of the antenna. Electronically controlled beam scanning can be achieved by loading tunable electronic components (such as PIN diodes, varactor diodes, MEMS switches, etc.) or tunable materials (ferroelectric material barium strontium titanate, optoelectronic material graphene, thermochromic material vanadium dioxide and water, liquid crystal, etc.), which has advantages such as simple structure, low cost, fast beam response speed and large beam scanning range.

[0023] like Figure 1 The diagram shows a side view of the schematic architecture of a 1-bit electrically controlled two-dimensional beam scanning antenna, which includes a circularly polarized antenna array 1, a phase compensation structure 2, a 1-bit phase shifter 3, a power divider network 4, and a beam control module 5 for controlling the scanning, connected in sequence.

[0024] The power divider network 4 is used to distribute the input electromagnetic wave signal into multiple equal-amplitude and in-phase electromagnetic power channels; the input terminal of the 1-bit phase shifter 3 is connected to the output terminal of the power divider network 4, and is used to perform 0° or 180° phase switching on the multiple signals; the phase compensation structure 2 is connected between the 1-bit phase shifter 3 and the circularly polarized antenna array 1, and is used to perform specific phase compensation on the phase-switched signal to suppress the symmetrical beam and sidelobes caused by 1-bit phase quantization; the circularly polarized antenna array 1 is used to radiate the phase-modulated and compensated signal into free space to form a circularly polarized beam.

[0025] The 1-bit phase shifter 3 includes a phase shifting structure and a bias circuit. The beam control module 5 is connected to the bias circuit. By controlling the bias state of the bias circuit, the phase state of the phase shifter is adjusted, thereby realizing the electronically controlled beam scanning of the antenna in a two-dimensional direction.

[0026] like Figure 2 , Figure 3 and Figure 4 This is a top view of the antenna's schematic diagram. The power divider network 4 can be constructed into a two-dimensional planar power divider network by cascading any number of 1-to-2 structures. The 1-bit phase shifter 3 and the phase compensation structure 2 can simultaneously power one circularly polarized antenna element and two circularly polarized elements (such as...). Figure 3 ) or four circularly polarized antenna elements (such as Figure 4 ) Feeding electromagnetic waves 6.

[0027] like Figure 5 The image shows a top view of an 8×8 circularly polarized antenna array arranged in a sequentially rotating manner. Each 2×2 element is a subarray, and the elements within the subarray are arranged in a clockwise rotation of 0°, 90°, 180°, and 270°.

[0028] like Figure 6 Another optional form of the 8×8 circularly polarized antenna array is arranged in a sequentially rotating manner, wherein each 2×2 element is a subarray, and the elements within the subarray are arranged in a counterclockwise rotation of 0°, 90°, 180°, and 270° in sequence.

[0029] like Figure 7 Another option for an 8×8 circularly polarized antenna array arranged in a sequential rotation, wherein the rotation angle of the element located in the m-th row and n-th column of the entire array is (m+n)×90°.

[0030] like Figure 8 and Figure 9 The images show top views of 4×4 and 16×16 1-bit circularly polarized antenna arrays, in which each array uses 2×2 elements as a subarray, and the elements within the subarray are arranged in a clockwise rotation of 0°, 90°, 180°, and 270°.

[0031] like Figure 10 This is a side view schematic diagram of a 1-bit circularly polarized antenna, including a 1-bit phase shifter 3, a phase compensation structure 2, and a circularly polarized antenna element connected in sequence. The 1-bit phase shifter 3 is used to achieve phase switching of 0° or 180°. The phase compensation structure 2 is used to provide specific phase compensation determined by an optimization algorithm to suppress symmetrical beams and reduce sidelobe levels. The circularly polarized antenna element is used to radiate electromagnetic waves into free space to form a circularly polarized beam. The 1-bit phase shifter 3 is also connected to a bias circuit to control its operating state.

[0032] like Figure 11 This is a side view of another 1-bit circularly polarized antenna, which shows the optional types of circularly polarized antenna elements. The circularly polarized antenna elements can adopt a single-feed, dual-feed, or multi-feed single-layer or multi-layer radiating patch structure, such as a single-feed dual-layer stacked radiating patch structure.

[0033] like Figure 12 A schematic diagram of the optional phase compensation structure is shown. The phase compensation structure can be selected from any one of the following: substrate integrated coaxial line, printed ridge gap waveguide, substrate integrated waveguide, dielectric waveguide, microstrip transmission line, stripline, coplanar waveguide, or slot line. By combining sequential rotation technology and introducing optimization algorithms to optimize the phase delay value, the symmetrical beam caused by 1-bit phase quantization can be effectively suppressed and the sidelobe level can be further reduced. The optimization algorithms include particle swarm optimization algorithm, genetic algorithm, simulated annealing algorithm, invasive weed optimization algorithm, or convex optimization algorithm, etc.

[0034] like Figure 13 This is a side view schematic diagram of a 1-bit phase shifter and its optional types. The 1-bit phase shifter includes a phase shifting structure and a bias circuit. The phase shifting structure can be selected from switch-line, load-line, high-pass-low-pass, or reflective phase shifting structures. The bias circuit is used to adjust the operating state of the phase shifter and includes a metal patch, metal vias, and active electronic components. The active electronic components are one or more of PIN diodes, varactor diodes, or MEMS switches, and are fixed on the metal patch. A DC bias line connects the metal patch to the beam control module 5 to provide bias voltage to the active electronic components.

[0035] like Figure 14 , Figure 15 , Figure 16 , Figure 17 and Figure 18 This diagram illustrates several possible feeding structures for the power divider network 4 in a 1-bit electrically controlled two-dimensional beam-scanning circularly polarized antenna. Figure 14 It is a parallel power supply structure. Figure 15 It is a series-fed structure. Figure 16 It is a reflector-fed structure. Figure 17 It is a lens-fed structure. Figure 18 As a multi-channel independent signal feeding structure, the power divider network 4 can be implemented using any of the above feeding methods.

[0036] like Figure 19 The diagram shows the beam scanning results. The power divider network 4 of the antenna uses a microstrip transmission line. Four T-junctions are cascaded to form a two-dimensional planar power divider network. Each output of the power divider network is fed by a 1-bit phase shifter 3. Each 1-bit phase shifter is then fed by a single phase compensation structure 3. The phase compensation structure is fed by a single circularly polarized antenna element, thus constructing a two-dimensional antenna. The circularly polarized antenna elements are arranged in a uniform manner. Figure 19 The given beam scanning results are normalized radiation patterns, corresponding to a scanning plane with an azimuth angle of 0° and a frequency of 24.5 GHz. Only 11 representative beams are given. In practice, more beam pointing can be generated through the beam control module.

[0037] Compared with mechanically rotating reflector antennas or array antennas, this invention has the advantages of fast beam response speed and no need for mechanical servo systems. Compared with traditional active phased arrays, this invention avoids the use of T / R components, thereby significantly reducing antenna costs. Compared with reconfigurable transmission / reflection arrays, this invention avoids the use of space-fed horns, avoids edge spillover losses, and effectively reduces profile. Compared with fixed-frequency beam-scanning leaky antennas, this invention avoids beam squinting problems caused by dispersion. Compared with linearly polarized planar discrete phase antenna arrays, this invention uses circularly polarized units, which can effectively suppress multipath effects and Faraday electromagnetic rotation effects. At the same time, this invention uses sequential rotation technology to effectively reduce the axial ratio of the antenna, and combined with phase compensation obtained by optimization algorithms, successfully suppresses the symmetrical beam caused by 1-bit quantization, effectively reducing the sidelobe level of the antenna.

[0038] The waveguide structure, phase shifter, and phase compensation structure of this invention all have the advantages of low transmission loss, low profile, easy processing, and easy integration, enabling the antenna to have advantages such as high gain, high efficiency, low profile, and lightweight. The radiation beam of this invention has wide-angle beam scanning, low axial ratio, high gain, and electronically controlled two-dimensional scanning characteristics. The radiating elements adopt a dense arrangement, and the beam has good continuity. The beam control module of this invention provides beam control coded signals for the antenna, controls the bias state of electronic components, and has fast response and high stability.

[0039] The circularly polarized antenna array in this invention reduces the axial ratio by employing sequential rotation technology. A phase compensation structure is connected between the output of the 1-bit phase shifter and the circularly polarized antenna array. This structure performs additional phase compensation on the signals of each channel to suppress the symmetrical beam caused by 1-bit phase quantization. Combined with an optimization algorithm, it reduces the sidelobe level of the array, enabling the antenna array to form the desired circularly polarized single beam in space and achieve two-dimensional scanning. The 1-bit phase shifter is located at the output of the power divider network to receive the power-divided electromagnetic wave signal and achieves 0° or 180° phase switching through its internal phase shifting structure and bias circuit. The beam control module is connected to the 1-bit phase shifter and regulates the phase state of each phase shifter by controlling the voltage state of the bias circuit. Through this structure, while ensuring high gain and two-dimensional electrically controlled beam scanning capability, it has advantages such as simple structure, low cost, thin profile, low power consumption, and ease of processing and integration, making it suitable for various wireless communication systems.

[0040] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A 1-bit electronically steerable two-dimensional beam scanning circularly polarized antenna, characterized in that, include: Circularly polarized antenna array (1), phase compensation structure (2), 1-bit phase shifter (3) and power divider network (4); The power divider network (4) is a two-dimensional planar power divider network composed of cascaded power divider structures, and includes multiple output terminals for receiving electromagnetic waves and distributing the electromagnetic waves into multiple outputs for output from multiple output terminals. Multiple 1-bit phase shifters (3) are disposed on the top surface of the power divider network (4), and each output terminal of the power divider network (4) is connected to the input terminal of a 1-bit phase shifter (3). Each 1-bit phase shifter (3) is used to switch the phase of an electromagnetic wave by 0° or 180°. The input terminals of the multiple phase compensation structures (2) are sequentially connected to the output terminals of multiple 1-bit phase shifters (3) for phase compensation of the multiple electromagnetic waves after phase switching; The circularly polarized antenna array (1) includes multiple arrays arranged on the surface of multiple phase compensation structures (2). Each circularly polarized antenna subarray includes circularly polarized units arranged in sequence at 0°, 90°, 180°, and 270°. The output of each phase compensation structure (2) feeds electromagnetic waves into the circularly polarized unit one-to-one through the feed point of the circularly polarized unit. The phase difference generated by the sequential rotation of the main polarized electromagnetic wave through the four circularly polarized units arranged in sequence at 0°, 90°, 180°, and 270° in the same circularly polarized antenna subarray is compensated by a 1-bit phase shifter (3) and the phase compensation structure (2) during beamforming. The phase difference of cross-polarization is not compensated and the cross-polarization cancels each other out, so as to synthesize a circularly polarized radiation field on the array aperture surface for scattering. It also includes a beam control module (5), which is connected to the bias circuit of the 1-bit phase shifter (3) and controls the bias state of the bias circuit to switch the phase of the electromagnetic wave signal to 0° or 180°. The circularly polarized antenna subarray comprises 2×2 circularly polarized elements; The 2×2 circularly polarized elements in the circularly polarized antenna subarray are arranged in a clockwise rotation of 0°, 90°, 180°, and 270°, or in a counterclockwise rotation of 0°, 90°, 180°, and 270°, respectively. The circularly polarized antenna array (1) can also be arranged by rotating M×N circularly polarized units in sequence, wherein the rotation angle of the circularly polarized unit located in the Mth row and Nth column of the circularly polarized antenna array (1) is (M+N)×90°, where M and N are positive integers; The 1-bit phase shifter (3) includes a phase shifting structure and a bias circuit; The phase-shifting structure adopts a self-switching line structure, a loaded line structure, a high-pass-low-pass structure, or a reflective phase-shifting structure; The bias circuit includes a metal patch, a metal via, and active electronic components, used to adjust the working state of the 1-bit phase shifter (3); the active electronic components are PIN diodes, varactor diodes, or MEMS switches. The circularly polarized antenna array (1) is arranged by rotating the circularly polarized elements in sequence or by rotating the circularly polarized antenna subarray in sequence.

2. The 1-bit electronically-controlled two-dimensional beam scanning circularly-polarized antenna according to claim 1, wherein, The circular polarization unit adopts a single-feed, dual-feed, or multi-feed single-layer or multi-layer radiating patch structure.

3. The 1-bit electronically-controlled two-dimensional beam scanning circularly-polarized antenna according to claim 1, wherein, The power splitting network (4) is a cascaded structure of 1 or 2 power splitting; The power distribution network (4) is a transmission line structure, employing rectangular waveguides, ridge waveguides, circular waveguides, parallel plate waveguides, gap waveguides, substrate integrated waveguides, dielectric waveguides, microstrip transmission lines, striplines, coplanar waveguides, or slot lines. The power distribution network (4) is fed in the form of parallel feeding, series feeding, reflective surface feeding, lens feeding or multi-channel independent signal feeding structure.

4. The 1-bit electronically-controlled two-dimensional beam scanning circularly-polarized antenna according to claim 1, wherein, The phase compensation structure (2) adopts substrate integrated coaxial line, printed ridge gap waveguide, substrate integrated waveguide, dielectric waveguide, microstrip transmission line, stripline, coplanar waveguide or slot line.

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