Transmission-reflection array antenna

Abstract

The present invention relates to the field of wireless communication technologies, and discloses a transmissive and reflective array antenna, which includes a feed source, a dielectric substrate, M×N transmissive units and m×n reflective units thereon; the transmissive unit includes two transmissive layers and two metal vias, the transmissive layer includes a first metal sheet and second metal sheets on both sides thereof, and two ends of the metal via are connected to two first metal sheets; the reflective unit includes a first reflective layer and a second reflective layer, the first reflective layer includes a third metal sheet and fourth metal sheets on both sides thereof, and the second reflective layer is a fifth metal sheet; the feed source can radiate orthogonal first polarization signals and second polarization signals to the side of the dielectric substrate; by adjusting the sizes of the respective metal sheets, the transmissive unit can generate a preset phase shift value for the transmitted electromagnetic wave, and the reflective unit can generate a preset phase shift value for the reflected electromagnetic wave, so that the antenna can achieve two-way communication to expand the signal coverage range and simultaneously form a radiation beam with a desired shape.

Description

Technical Field

[0001] The present invention relates to the field of wireless communication technologies, and in particular, to a transmit-reflectarray antenna. Background Art

[0002] With the rapid development of wireless communication technologies, the demand for faster and more reliable communication poses a huge challenge. As a key part of the transceiver terminal, the antenna is crucial for improving the transmission quality of wireless systems. To obtain a larger communication capacity, the millimeter-wave 5G band is an important part of mobile communication systems and can support higher data transmission rates. However, due to its high-frequency characteristics, the signal transmission distance in the millimeter-wave band is relatively short, and it is vulnerable to the influence of obstacles and attenuation, resulting in a decline in communication quality. In the research of the millimeter-wave 5G band, the design of broadband antennas applied to large-capacity communication systems can overcome the limitation of short signal transmission distance and improve communication quality and reliability. To overcome the disadvantage that millimeter-wave signals are vulnerable to obstacles, a bidirectional antenna combining transmission and reflection can be designed. The bidirectional antenna has two opposite beam directions and can achieve better coverage. Designing an antenna that can generate multiple beams simultaneously can improve the system capacity and coverage. At the same time, using antenna arrays with different polarizations can improve the signal transmission efficiency and reduce the influence of multipath effects.

[0003] In some bidirectional antennas combining partial transmission and reflection, the polarization conversion is mainly achieved by rotating the feed horn at present, so as to realize the switching of transmission and reflection beams. However, the response time of rotating the feed horn mechanically is long and cannot adapt to a rapidly changing communication environment. Summary of the Invention

[0004] The present invention is made to solve the above technical problems. One of its purposes is to provide a transmit-reflectarray antenna that can achieve bidirectional communication to expand the signal coverage range.

[0005] Another purpose of the present invention is to provide a transmit-reflectarray antenna that can form different deflected beams for the transmitted and reflected signals to increase the signal strength in a specific area.

[0006] Still another purpose of the present invention is to provide a transmit-reflectarray antenna that can output signals with orthogonal polarization without rotating the feed horn.

[0007] To achieve the above object, the present invention provides a transmissive-reflective array antenna, which includes a feed source and a transmissive-reflective array. The transmissive-reflective array includes a dielectric substrate and M×N transmissive units and m×n reflective units arranged periodically thereon. Each of the reflective units and transmissive units is arranged alternately. Wherein the transmissive unit includes transmissive layers provided on both sides of the dielectric substrate and two metal vias connecting the two transmissive layers. The transmissive layer includes a first metal sheet and second metal sheets on both sides thereof. The two ends of the metal via are connected to the first metal sheet, and the length of the first metal sheet is L t , and the length of the second metal sheet is 0.72L t , and the distance between the metal vias is 0.2L t , adjusting the value of L t can make the transmissive unit generate a preset phase shift value for the transmitted electromagnetic wave; the reflective unit includes a first reflective layer and a second reflective layer provided on both sides of the dielectric substrate respectively. The first reflective layer is provided on the side of the dielectric substrate close to the feed source. The first reflective layer includes a third metal sheet and fourth metal sheets on both sides thereof. The second reflective layer is a fifth metal sheet. The length of the third metal sheet is L r , and the length of the fourth metal sheet is 0.72L r , adjusting the value of L r can make the reflective unit generate a preset phase shift value for the reflected electromagnetic wave; when the feed source radiates a first polarization signal to the side of the dielectric substrate, the transmissive unit deflects the first polarization signal by a preset phase to form a radiation beam with a preset shape; when the feed source radiates a second polarization signal orthogonal to the first polarization signal to the side of the dielectric substrate, the reflective unit deflects the second polarization signal by a preset phase to form a radiation beam with a preset shape.

[0008] As an embodiment, the phase shift value of each transmissive unit for the electromagnetic wave in the N258 frequency band is , , where , mm, .

[0009] As an embodiment, the phase shift value of each reflective unit for the electromagnetic wave in the N258 frequency band is , , , mm, .

[0010] As an embodiment, the phase shift value of each transmissive unit and reflective unit and the angle of the single-beam electromagnetic wave radiated The relationship is as follows: ,

[0011] In the formula, is the actual radiation phase of the feed on the array, taking as the compensation phase, is the wavelength of the electromagnetic wave at the center frequency of the N258 band, x and y are the index coordinates of each transmission unit on the dielectric substrate respectively, represents the elevation angle of the beam, represents the azimuth angle of the beam.

[0012] As an implementation manner, the transmission unit generates a deflection of a preset phase for the first polarization signal, and transmits and forms a single-beam electromagnetic wave with a deflection of +20°.

[0013] As an implementation manner, the phase shift values of each of the transmission units and the reflection units and the angle of the multi-beam electromagnetic wave radiated The relationship is as follows:

[0014] ,

[0015] In the formula, i is the beam number, is the actual radiation phase of the feed on the array, taking as the compensation phase, is the wavelength of the electromagnetic wave at the center frequency of the N258 band, x and y are the index coordinates of each radiation unit on the dielectric substrate respectively, represents the elevation angle of each beam, represents the azimuth angle of each beam.

[0016] As an implementation manner, the reflection unit generates a deflection of a preset phase for the second polarization signal, and reflects and forms a dual-beam electromagnetic wave with a deflection of ±30°.

[0017] As an implementation manner, the fifth metal sheet is of a rectangular structure, and a preset part is cut off at four corners.

[0018] As an implementation manner, the feed includes a main radiation patch and a first SIW feeding structure and a second SIW feeding structure that are connected to and orthogonally arranged with the main radiation patch. The first SIW feeding structure is used to transmit a first polarization signal to the main radiation patch, and the second SIW feeding structure is used to transmit a second polarization signal to the main radiation patch.

[0019] As an embodiment, the main radiation patch includes two pairs of symmetrically split dipole structures, and four notched rings are arranged around the main radiation patch.

[0020] According to the above description and practice, the transmissive-reflective array antenna of the present invention can be targeted at signals of different polarizations, and can respectively produce transmissive and reflective effects, and then radiate signals in two directions, enabling two-way communication and expanding the signal coverage range. In addition, by setting the specific parameters of each transmissive unit and each reflective unit, the transmissive and reflective signals can be formed into different deflected beams to increase the signal strength in a specific area. Compared with the traditional transmissive or reflective array antenna that can only radiate on one side, the antenna in the present invention can radiate signals in two different directions only by controlling the feed source to input signals of different polarizations, can adapt to a more complex communication system, and is flexible and variable.

[0021] In addition, the transmissive-reflective array antenna of the present invention can change the polarization mode of the fed signal only by changing the feed port of the feed source, so as to achieve the switching between the transmissive beam and the reflective beam, and has the flexibility and simplicity of mode switching. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 and Figure 2 are schematic three-dimensional structure diagrams of the transmissive-reflective array antenna involved in an embodiment of the present invention from two different perspectives.

[0023] Figure 3 is a perspective view of a transmissive unit in the transmissive-reflective array antenna involved in an embodiment of the present invention.

[0024] Figure 4 is a perspective view of a reflective unit in the transmissive-reflective array antenna involved in an embodiment of the present invention.

[0025] Figure 5 is a schematic structural diagram of the top surface of the transmissive-reflective array in the transmissive-reflective array antenna involved in an embodiment of the present invention.

[0026] Figure 6 is a schematic structural diagram of the bottom surface of the transmissive-reflective array in the transmissive-reflective array antenna involved in an embodiment of the present invention.

[0027] Figure 7a and Figure 7b is a schematic structural diagram of the feed source in the transmissive-reflective array antenna involved in an embodiment of the present invention, where Figure 7b is a perspective view.

[0028] Figure 8a and Figure 8bSchematic diagram of the electric field on the top surface of the transmissive and reflective array of the transmissive and reflective array antenna involved in an embodiment of the present invention, where Figure 8a the end of the fifth metal sheet in Figure 8b has no chamfer,

[0029] Figure 9a Schematic diagram of the phase compensation of each transmissive unit when the transmissive and reflective array antenna involved in an embodiment of the present invention transmits a single beam with a deflection of +20°.

[0030] Figure 9b Schematic diagram of the phase compensation of each reflective unit when the transmissive and reflective array antenna involved in an embodiment of the present invention reflects a double beam with a deflection of ±30°.

[0031] Figure 10 Bandwidth and gain performance diagram of the feed of the transmissive and reflective array antenna involved in an embodiment of the present invention.

[0032] Figures 11a to 11d EH-plane beam radiation pattern of the feed of the transmissive and reflective array antenna involved in an embodiment of the present invention at different frequency points, where Figure 11a is 24 GHz, Figure 11b is 26 GHz, Figure 11c is 28 GHz, Figure 11d is 30 GHz.

[0033] Figure 12a Length L of the third metal sheet in the transmissive and reflective array antenna involved in an embodiment of the present invention r Relationship diagram with the transmission amplitude of electromagnetic waves in the N258 frequency band.

[0034] Figure 12b Length L of the first metal sheet in the transmissive and reflective array antenna involved in an embodiment of the present invention t Relationship diagram with the reflection amplitude of electromagnetic waves in the N258 frequency band.

[0035] Figure 13a Length L of the first metal sheet in the transmissive and reflective array antenna involved in an embodiment of the present invention t Relationship diagram with the phase shift value of electromagnetic waves in the N258 frequency band.

[0036] Figure 13b Length L of the third metal sheet in the transmissive and reflective array antenna involved in an embodiment of the present invention r Relationship diagram with the phase shift value of electromagnetic waves in the N258 frequency band.

[0037] Figure 14 Gain diagram of the transmissive and reflective array antenna involved in an embodiment of the present invention in the N258 frequency band.

[0038] Figures 15a to 15c In an embodiment of the present invention, when the transmit-reflectarray antenna feeds a first polarization signal through the first SIW feeding structure and realizes the transmit deflection +20° single-beam effect, the radiation patterns at different frequency points are as follows, where, Figure 15a is 24 GHz, Figure 15b is 26 GHz, Figure 15c is 27.5 GHz.

[0039] Figures 16a to 16c In an embodiment of the present invention, when the transmit-reflectarray antenna feeds a second polarization signal through the second SIW feeding structure and realizes the reflect deflection ±30° dual-beam effect, the radiation patterns at different frequency points are as follows, where, Figure 16a is 24 GHz, Figure 16b is 26 GHz, Figure 16c is 27.5 GHz.

[0040] The reference numerals in the figure are:

[0041] 1, feedhorn; 2, transmit unit

[0042] 3, reflect unit; 4, dielectric substrate

[0043] 11, first SIW feeding structure; 12, second SIW feeding structure

[0044] 13, main radiation patch; 14, split ring

[0045] 51, first metal sheet; 52, second metal sheet

[0046] 53, third metal sheet; 54, fourth metal sheet

[0047] 55, fifth metal sheet; 56, metal via hole. Detailed implementation manners

[0048] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, the exemplary embodiments can be implemented in various forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the exemplary embodiments to those skilled in the art. The features, structures, or characteristics described may be combined in any suitable manner in one or more embodiments.

[0049] In addition, the accompanying drawings are only schematic illustrations of the present disclosure and are not necessarily drawn to scale. The same reference numerals in the drawings denote the same or similar parts, and thus repeated descriptions thereof will be omitted. It should be noted that in the present disclosure, the terms "comprising", "configured with", and "provided with" are used to mean an open inclusion, and it means that there may be additional elements, components, etc. in addition to the listed elements / components / etc.; the terms "first", "second", etc. are only used as labels and are not limitations on the quantity or order of their objects; the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be construed as a limitation on the present invention.

[0050] Unless otherwise clearly defined and limited, the terms "mounted", "connected", and "coupled" shall be construed broadly. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the internal communication of two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0051] In this embodiment, a transmissive-reflective array antenna is disclosed. Please refer to Figures 1 to 7b , the transmissive-reflective array antenna includes a feed source 1 and a transmissive-reflective array. The feed source 1 is used to radiate a signal to the transmissive-reflective array, and then the transmissive-reflective array transmits or reflects the signal. At the same time, during the transmission and reflection processes, a preset phase shift is generated for the signal, and finally a beam with a preset shape is radiated outward. The transmitted signal and the reflected signal are directed in different directions, thus constituting a bi-directional antenna.

[0052] Specifically, the transmissive-reflective array includes a dielectric substrate 4 and M×N periodically arranged transmissive units 2 and m×n periodically arranged reflective units ③ on it. The respective reflective units 3 and transmissive units 2 are alternately arranged. As Figure 1 and Figure 2 shown, in this embodiment, a total of 15×15 transmissive units 2 are provided, and a total of 14×14 reflective units 3 are provided to form better transmissive and reflective beams for the signal output by the feed source 1.

[0053] Please refer to Figure 3, the transmission unit 2 includes a transmission layer provided on both sides of the dielectric substrate 4 and two metal vias 56 connecting the two transmission layers. Each transmission layer includes a first metal sheet 51 and second metal sheets 52 on both sides thereof, and both ends of the two metal vias 56 are connected to the first metal sheet 51. The length of the first metal sheet 51 is L t , the length of the second metal sheet 52 is 0.72L t , the distance between the metal vias 56 is 0.2L t . Adjusting the value of L t can cause the transmission unit 2 to generate a preset phase shift value for the transmitted electromagnetic wave. As shown in Figure 13a , different values of L t can generate different phase shift values for the electromagnetic wave in the N258 frequency band. Therefore, by setting the values of L t in each of the 15×15 transmission units 2, each transmission unit 2 can generate a preset phase shift value for the transmitted signal, and finally transmit a radiation beam with a preset shape. In each transmission unit 2, the upper and lower transmission layers form a multi-resonant dipole, and there is a weak coupling between the upper and lower dipole layers. The metal vias 56 can transmit energy between the upper dipole and the lower dipole, increasing the coupling between the upper and lower dipole layers and improving the transmission efficiency. Thus, good transmission amplitude-phase characteristics can be achieved by simultaneously changing the length of the dipole arms and the distance between the metal vias.

[0054] Please refer to Figure 4 , the reflection unit 3 includes a first reflection layer and a second reflection layer respectively provided on both sides of the dielectric substrate 4. The first reflection layer is provided on the side of the dielectric substrate 4 close to the feed source 1, and the first reflection layer includes a third metal sheet 53 and fourth metal sheets 54 on both sides thereof. The second reflection layer is a fifth metal sheet 55. The length of the third metal sheet 53 is L r , the length of the fourth metal sheet 54 is 0.72L r . Adjusting the value of L r can cause the reflection unit 3 to generate a preset phase shift value for the reflected electromagnetic wave. As shown in Figure 13b , different values of L r can generate different phase shift values for the electromagnetic wave in the N258 frequency band. Therefore, by setting the values of L r in each of the 14×14 reflection units 3, each reflection unit 3 can generate a preset phase shift value for the reflected signal, and finally reflect a radiation beam with a preset shape. The metal sheets in the first reflection layer form a multi-resonant dipole, cooperate with the reflector formed by the fifth metal sheet 55, and good reflection amplitude-phase characteristics are achieved by changing the length of the dipole arms.

[0055] In this embodiment, the feed source 1 can radiate orthogonal first polarization signals or second polarization signals to the side of the dielectric substrate 4. When the feed source 1 radiates first polarization signals to the side of the dielectric substrate 4, the transmission unit 2 deflects the first polarization signals by a preset phase to form a radiation beam with a preset shape, and the reflection unit 3 cannot reflect the first polarization signals. When the feed source 1 radiates second polarization signals orthogonal to the first polarization signals to the side of the dielectric substrate 4, the reflection unit 3 deflects the second polarization signals by a preset phase to form a radiation beam with a preset shape, and the transmission unit 2 cannot transmit the second polarization signals.

[0056] This transmit-reflect array antenna can respectively produce transmission and reflection effects for signals of different polarizations, and then radiate signals in two directions, enabling two-way communication and expanding the signal coverage range. In addition, by setting the specific parameters of each transmission unit 2 and each reflection unit 3, the transmitted and reflected signals can be formed into different deflected beams to improve the signal strength in a specific area. Compared with traditional transmit or reflect array antennas that can only radiate on one side, the antenna in the present invention can radiate signals in two different directions only by controlling the feed source 1 to input signals of different polarizations, can adapt to more complex communication systems, and is flexible and variable.

[0057] Specifically, in this embodiment, the transmission unit 2 and the reflection unit 3 are arranged perpendicular to each other and staggered, as Figure 1 、 Figure 2 、 Figure 5 and Figure 6 shown. The first metal sheet 51 is parallel to the second metal sheet 52, the third metal sheet 53, the fourth metal sheet 54 and the fifth metal sheet 55 are parallel, the first metal sheet 51 is perpendicular to the third metal sheet 53, and the first metal sheet 51 is perpendicular to the fifth metal sheet 55, which can reduce the coupling effect between the two radiation units, improve the isolation degree, and avoid mutual interference between the two radiation units during the array phase compensation calculation, so that the phase compensation of the two radiation units can be calculated separately, greatly simplifying the design process of each radiation unit. In addition, the second metal sheet 52 is shorter than the first metal sheet 51, and the fourth metal sheet 54 is shorter than the third metal sheet 53, which can increase the distance between the transmission layer and the first reflection layer to a certain extent and further reduce the coupling effect between the two radiation units.

[0058] Furthermore, in this embodiment, the fifth metal sheet 55 is of a rectangular structure, and a preset part is cut off at the four corners. As Figure 1 and Figure 5 shown, a triangular area is cut off at each of the four corners of the fifth metal sheet 55, increasing the distance from the adjacent transmission layer and further improving the isolation degree between the reflection unit 3 and the radiation unit. As Figure 8a and Figure 8bAs shown, when the radiation output from the feed 1 can excite the reflection unit 3, if the fifth metal sheet 55 has no chamfer, there is a strong coupling between the transmission layer and the fifth metal sheet 55, and the transmission layer also excites an induced electric field. After chamfering the fifth metal sheet 55, there is almost no electric field on the transmission layer. Therefore, chamfering the fifth metal sheet 55 significantly reduces the coupling between the two units and improves the isolation between the two structures. In other embodiments, arc-shaped, fan-shaped or other shaped regions can also be cut off at the four corners of the fifth metal sheet 55, and to a certain extent, the coupling effect between adjacent radiation units can be reduced.

[0059] In addition, in combination with Figure 12a and Figure 12b , Figure 12a shows the influence of changing the length L r of the third metal sheet 53 in the reflection unit 3 on the transmission amplitude of the transmission unit 2, Figure 12b and t shows the influence of changing the length L

[0060] of the first metal sheet 51 in the transmission unit 2 on the reflection amplitude of the reflection unit 3. It can be seen from the figure that in the corresponding frequency band, the transmission amplitude is > 0.7 and the reflection amplitude is > 0.9, indicating that the parameter changes between the two unit structures have little influence on the amplitude and the isolation is high.

[0060] In a specific embodiment, the phase shift value of the transmission unit 2 for electromagnetic waves in the N258 frequency band is , and this phase shift value has the following relationship with the L t value in the transmission layer:

[0061] (1)

[0062] where , mm, .

[0063] It should be noted that the N258 frequency band mainly includes 24 GHz - 28 GHz. As Figure 13a shown, when changing the L t value, the transmission unit 2 will generate different but close phase shift values for electromagnetic waves at 24 GHz, 25 GHz, 26 GHz, 27 GHz and 28 GHz frequency points, and the change trend of the phase shift values at each frequency point with the L t value is approximate. Since this antenna needs to be applicable to the entire N258 frequency band, the relationship between the phase shift value corresponding to the 26 GHz electromagnetic wave and the L t value is applied to the entire N258 frequency band. Correspondingly, the above is the phase shift value generated when the 26 GHz electromagnetic wave passes through the transmission unit 2 with a length of 4.6 mm.

[0064] Please combine with Figure 13a , by adjusting the value of L t , the transmission unit 2 can generate a phase shift in the range of nearly 340° for the electromagnetic wave in the N258 frequency band, which can meet the requirements of most beam adjustments.

[0065] Similarly, in this embodiment, the phase shift value of the reflection unit 3 for the electromagnetic wave in the N258 frequency band is , and this phase shift value has the following relationship with the value of L r in the first reflection layer:

[0066] (2)

[0067] , mm, .

[0068] It should be noted that the N258 frequency band mainly includes 24 GHz - 28 GHz. As Figure 13b shown, when changing the value of L r , the reflection unit 3 will generate different but close phase shift values for the electromagnetic waves at the 24 GHz, 25 GHz, 26 GHz, 27 GHz, and 28 GHz frequency points, and the change trend of the phase shift values at each frequency point with the value of L r is approximately the same. Since this antenna needs to be applicable to the entire N258 frequency band, the relationship between the phase shift value corresponding to the 26 GHz electromagnetic wave and the value of L r is applied to the entire N²⁵⁸ frequency band. Correspondingly, the above is the phase shift value generated when the electromagnetic wave with a frequency of 26 GHz passes through the reflection unit 3 with a length of 4.6 mm.

[0069] Please combine with Figure 13b , by adjusting the value of Lr, the reflection unit 3 can generate a phase shift in the range of nearly 360° for the electromagnetic wave in the N258 frequency band, which can meet the requirements of most beam adjustments.

[0070] When designing the parameters of the structures of each transmission unit 2 and reflection unit 3, the distance between the feed source 1 and the transmission - reflection array is known, and the initial phase of the electromagnetic wave reaching the transmission - reflection array is also known. If a specific - shaped reflected beam and transmitted beam are required, each reflection unit 3 and transmission unit 2 needs to generate a specific phase shift value for the electromagnetic wave at its location.

[0071] In one embodiment, taking the electromagnetic wave of the externally transmitted and reflected single beam as an example, the phase shift values of each transmission unit 2 and reflection unit 3 and the angle of the radiated single - beam electromagnetic wave There is the following relationship:

[0072] (3)

[0073] In the formula, is the actual radiation phase of the feed source 1 on the array, taking as the compensation phase, is the wavelength of the electromagnetic wave at the center frequency of the N258 band, x and y are the index coordinates of each radiation unit on the dielectric substrate respectively, represents the elevation angle of the beam radiated by the array, represents the azimuth angle of the beam radiated by the array.

[0074] Therefore, according to the elevation angle and azimuth angle of the electromagnetic wave beam with the required shape, the phase shift values required for each transmission unit 2 and reflection unit 3 can be calculated using formula (3), and then the L t value in each transmission unit 2 and the L r value in each reflection unit 3 can be calculated using formulas (1) and (2).

[0075] In another embodiment, taking the electromagnetic wave of external transmission and reflection of multiple beams as an example, the phase shift values of each transmission unit 2 and reflection unit 3 have the following relationship with the angle (4)

[0076] (5)

[0077] In the formula, i is the beam number. For example, when radiating an electromagnetic wave of dual beams, i are 1 and 2 respectively. j is the imaginary unit. is the actual radiation phase of the feed source 1 on the array, taking as the compensation phase, is the wavelength of the electromagnetic wave at the center frequency of the N258 band, x and y are the index coordinates of each radiation unit on the dielectric substrate 4 respectively, represents the elevation angle of each beam radiated by the array, represents the azimuth angle of each beam radiated by the array.

[0078] Therefore, according to the elevation angle and azimuth angle of each beam in the multi-beam electromagnetic wave of the required shape, the phase shift values required for each transmission unit 2 and reflection unit 3 to form the corresponding single beam can be calculated using formula (4). Then, using formula (5) and through vector superposition, the phase shift values required for each transmission unit 2 and reflection unit 3 for the corresponding multi-beam electromagnetic wave can be calculated. Finally, the L values in each transmission unit 2 can be calculated using formulas (1) and (2). t values and the L r values in each reflection unit 3.

[0079] In the above manner, a transmission-reflection array antenna with corresponding specifications can be designed according to the beam shape required in practice. This antenna can exhibit good amplitude and phase characteristics in the N258 frequency band, and has the characteristics of wide frequency band, wide phase coverage, and good transmission and reflection amplitudes.

[0080] Next, taking the transmission unit 2 deflecting the first polarization signal transmitted by the feed source 1 to generate a preset phase and transmitting to form a single-beam electromagnetic wave with a deflection of +20° as an example, and taking the reflection unit 3 deflecting the second polarization signal transmitted by the feed source 1 to generate a preset phase and reflecting to form a dual-beam electromagnetic wave with a deflection of ±30° as an example, the antenna will be further described.

[0081] Specifically, in this embodiment, a total of 15×15 transmission units 2 are set, and a total of 14×14 reflection units 3 are set. The outer dimensions of each radiation unit are 5.8×5.8×1 mm, the substrate is a Rogers 5880 board with a thickness of 1 mm, and the dielectric constant is 2.2. The length and width of the transmission-reflection array are 90×90 mm, and the selected focal ratio F / D = 0.7.

[0082] In this embodiment, the widths of the first metal sheet 51 and the second metal sheet 52 in the transmission layer are the same, both being 0.037 , and the distance between the first metal sheet 51 and the second metal sheet 52 is 0.016 . The widths of the third metal sheet 53 and the fourth metal sheet 54 in the reflection layer are the same, both being 0.037 , and the distance between the third metal sheet 53 and the fourth metal sheet 54 is 0.016 . The length of the fifth metal sheet 55 is 0.399 and the width is 0.191 , and the chamfered area is an isosceles right triangle with a width of 0.052 . is the wavelength of the electromagnetic wave at the center frequency of the N258 frequency band.

[0083] Through the calculation of the above formulas, the phase shift values required for each transmission unit 2 and reflection unit 3 can be obtained. For details, seeFigure 9a and Figure 9b , and then the specific parameters of the corresponding structures of each transmission unit 2 and reflection unit 3 can be calculated accordingly.

[0084] In order to conveniently and quickly radiate the above-mentioned first polarization signal and second polarization signal to the transmission-reflection array, the feed source 1 in this embodiment is set in a structural form of a main radiation patch 13 and two orthogonally arranged SIW feed structures. During actual use, without mechanically rotating the feed source 1, it is possible to switch between outputting the first polarization signal and outputting the second polarization signal.

[0085] Specifically, please refer to Figure 1 , Figure 2 , Figure 7a and Figure 7b , the feed source 1 includes a main radiation patch 13 and a first SIW feed structure 11 and a second SIW feed structure 12 which are orthogonally arranged and communicated with it.

[0086] One end of the first SIW feed structure 11 is provided with a first port to access the first polarization signal, and the other end is connected to the main radiation patch 13 through a cross slot to transmit the first polarization signal to the main radiation patch 13, and then radiated from the main radiation patch 13 to the transmission-reflection array. After the signal is phase-compensated by each transmission unit 2, a single-beam electromagnetic wave deflected by +20° is formed.

[0087] One end of the second SIW feed structure 12 is provided with a second port to access the second polarization signal, and the other end is connected to the main radiation patch 13 through a cross slot to transmit the second polarization signal to the main radiation patch 13, and then radiated from the main radiation patch 13 to the transmission-reflection array. After the signal is phase-compensated by each reflection unit 3, a double-beam electromagnetic wave deflected by ±30° is formed. Among them, the single-beam electromagnetic wave formed by transmission and the double-beam electromagnetic wave formed by reflection are in opposite directions, so that the antenna can realize bidirectional signal transmission by only switching the feed port without mechanical rotation.

[0088] Furthermore, in this embodiment, the main radiation patch 13 includes two pairs of symmetric split dipole structures, and four notch rings 14 are arranged around it. There is also a patch in the shape of a square frame in the middle of the notch rings 14. By cooperating with two orthogonally arranged SIW feed structures, orthogonal dual polarization is realized. Among them, the notch rings 14 and the patch in the shape of a square frame are both parasitic patches, and the two can be regarded as parasitic ring structures. For the current of each polarization, it can be regarded as the current in the main polarization direction of the driving dipole, and the energy is coupled to the parasitic ring. In the direction of cross polarization, the currents will cancel each other out, thus achieving a good cross-polarization effect. By adding notch rings 14 around the split dipole, the direction of the current is changed, and stable gain and radiation pattern are achieved within the entire bandwidth.

[0089] As shown Figure 10 , Figures 11a to 11d in the figure, the bandwidth of the feed 1 covers 23.8 - 30.5 GHz (<-10 dB), and the gain is 8 ± 1.5 dBi. A stable radiation pattern can be achieved within the entire bandwidth. The 3dB beamwidth in the E-plane is 67°, the 3dB beamwidth in the H-plane is 75°, and the cross-polarization level is <-22 dB, which can meet the index requirements of the feed 1 for the transmissive array and the reflective array.

[0090] As shown Figure 14 in the figure, which shows the gain performance diagram of the transmissive-reflective array antenna in this embodiment at the N258 frequency band when fed through different ports, achieving the transmissive single-beam effect and the reflective double-beam effect. It can be seen from the figure that the highest gain of the single beam can reach 22.3 dBi, and the 1dB gain bandwidth is 7% (24.7 - 26.5 GHz). The highest gain of the double beam can reach 20.55 dBi, and the 1dB gain bandwidth is 9.5% (25.0 - 27.5 GHz). It shows that the antenna has good gain in both directions.

[0091] As shown Figures 15a to 15c in the figure, which shows the radiation pattern of the transmissive-reflective array antenna in this embodiment at the N258 frequency band when the first polarization signal is fed through the first SIW feeding structure 11 and the transmissive deflection +20° single-beam effect is achieved. It can be seen from the figure that the single-beam deflection effect is stable within the target frequency band, and the sidelobe suppression is <-12.5 dB.

[0092] As shown Figures 16a to 16c in the figure, which shows the radiation pattern of the transmissive-reflective array antenna in this embodiment at the N258 frequency band when the first polarization signal is fed through the first SIW feeding structure 11 and the transmissive deflection +20° single-beam effect is achieved. It can be seen from the figure that the symmetric double-beam effect is stable within the target frequency band, and the sidelobe suppression is <-12.2 dB.

[0093] In other embodiments, according to actual requirements, the number of transmissive units 2 and reflective units 3 in the transmissive-reflective array can also be changed, that is, the values of M, N, m, and n are changed. When the required beam shape and focal diameter ratio are known, the specific parameters of the structures in each transmissive unit 2 and reflective unit 3 can also be calculated according to the above formula.

[0094] It is obvious to those skilled in the art that the present invention is not limited to the details of the above-described exemplary embodiments, and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be embraced within the present invention. Any reference signs in the claims should not be construed as limiting the claims concerned.

Claims

1. A transmissive and reflective array antenna, characterized in that, Comprising a feed source and a transmissive-reflective array, the transmissive-reflective array includes a dielectric substrate and M×N periodically arranged transmissive elements and m×n periodically arranged reflective elements thereon, and each of the reflective elements and transmissive elements are alternately arranged; wherein The transmission unit includes a transmission layer provided on both sides of the dielectric substrate and two metal vias connecting the two transmission layers. The transmission layer includes a first metal sheet and second metal sheets on both sides thereof. Both ends of the metal via are connected to the first metal sheet, and the length of the first metal sheet is L t , the length of the second metal sheet is 0.72L t , the distance between the metal vias is 0.2L t , adjusting the value of L t can cause the transmission unit to generate a preset phase shift value for the transmitted electromagnetic wave; The reflection unit includes a first reflection layer and a second reflection layer respectively disposed on two sides of the dielectric substrate. The first reflection layer is disposed on one side of the dielectric substrate close to the feed source. The first reflection layer includes a third metal sheet and fourth metal sheets on both sides thereof. The second reflection layer is a fifth metal sheet, and the length of the third metal sheet is L r , and the length of the fourth metal sheet is 0.72L r , adjusting the value of L r can cause the reflection unit to generate a preset phase shift value for the reflected electromagnetic wave; The feed source includes a main radiation patch and a first SIW feeding structure and a second SIW feeding structure which are orthogonally arranged and communicated with the main radiation patch. The first SIW feeding structure is used to transmit a first polarization signal to the main radiation patch, and the second SIW feeding structure is used to transmit a second polarization signal to the main radiation patch. When the feed source radiates the first polarization signal to the dielectric substrate side, a deflection with a preset phase of the first polarization signal is generated by the transmission unit to form a radiation beam with a preset shape. When the feed source radiates a second polarization signal orthogonal to the first polarization signal to the dielectric substrate side, a deflection with a preset phase of the second polarization signal is generated by the reflection unit to form a radiation beam with a preset shape. The phase shift values of each of the transmission units and the reflection units and the angles of the multi-beam electromagnetic waves radiated have the following relationship: In the formula, i is the beam number, is the actual radiation phase of the feed source on the array, taking as the compensation phase, is the wavelength of the electromagnetic wave at the center frequency of the N258 frequency band, x and y are the index coordinates of each radiation unit on the dielectric substrate respectively, represents the elevation angle of each beam, represents the azimuth angle of each beam.

2. The transmissive-reflective array antenna according to claim 1, characterized in that The phase shift value of each of the transmission units for electromagnetic waves in the N258 frequency band is , 3. The transmissive-reflective array antenna according to claim 1, characterized in that The phase shift value of each of the reflection units for electromagnetic waves in the N258 frequency band is , 4. The transmissive-reflective array antenna according to claim 1, characterized in that Phase shift values of each of the transmission units and reflection units and the angle of the single-beam electromagnetic wave radiated are related as follows: In the formula, is the actual radiation phase of the feed on the array, taking as the compensation phase, is the wavelength of the electromagnetic wave at the center frequency of the N258 band, x and y are the index coordinates of each transmission unit on the dielectric substrate respectively, represents the elevation angle of the beam, represents the azimuth angle of the beam.

5. The transmissive-reflective array antenna according to claim 4, characterized in that The transmissive element deflects the first polarization signal by a preset phase, and transmits and forms a single-beam electromagnetic wave with a deflection of +20°.

6. The transmissive-reflective array antenna according to claim 1, characterized in that The reflective element deflects the second polarization signal by a preset phase, and reflects and forms a dual-beam electromagnetic wave with a deflection of ±30°.

7. The transmissive-reflective array antenna according to claim 1, characterized in that The fifth metal sheet is of a rectangular structure, and a preset part is cut off at four corners thereof.

8. The transmissive-reflective array antenna according to claim 1, characterized in that The main radiation patch includes two pairs of symmetric split dipole structures, and four notched rings are arranged around the main radiation patch.

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