Disclosure of Invention
The invention aims to: the high-isolation double-frequency dual-polarized array antenna for the millimeter wave frequency band is provided, and the millimeter wave array antenna is large in bandwidth, large in gain, good in phase scanning capacity and good in isolation effect in a small size.
The technical scheme of the invention is as follows: the utility model provides a high isolation dual-frenquency dual polarization array antenna for millimeter wave frequency channel from top to bottom includes in proper order: the antenna comprises a parasitic antenna layer, a first dielectric layer, a radiation antenna layer and a first metal stratum; the parasitic antenna layer comprises a parasitic antenna array consisting of at least one resonant parasitic antenna unit; the radiation antenna layer comprises a radiation antenna array consisting of at least one multi-frequency resonance antenna unit, and a decoupling structure is arranged between every two adjacent multi-frequency resonance antenna units; the first dielectric layer is a dielectric substrate between the resonant parasitic antenna unit and the multi-frequency resonant antenna unit; and a feed port is arranged on the first metal layer and is connected with the corresponding multi-frequency resonance antenna unit through a feed column.
The dual-frequency antenna has the advantages that the dual-layer antenna stacking structure is used for meeting the requirement of dual frequency and reducing the size of the antenna, and the decoupling structure is arranged between two adjacent multi-frequency resonant antenna units, so that the coupling of a multi-frequency multi-antenna system with limited space is reduced, and the working performance of the original antenna array is kept.
The further technical scheme is as follows: the decoupling structure comprises an I-shaped resonator arranged between two adjacent multi-frequency resonance antenna units on the radiation antenna layer and a C-shaped annular groove etched on the first metal ground layer.
The band-stop filter is formed by equivalently etching a C-shaped annular groove on the first metal stratum, the reactive resistance of the equivalent band-stop filter can be changed by adjusting the size and the position of the C-shaped annular groove, the isolation between the antenna units is improved, an I-shaped resonator is arranged between two adjacent multi-frequency resonance antenna units, and the coupling currents between the antenna units are mutually offset by changing the size and the position of the I-shaped resonator, so that the isolation between the antenna units is improved.
The further technical scheme is as follows: the multi-frequency resonance antenna unit adopts a low-frequency antenna and works at 26 GHz; the multi-frequency resonance antenna unit is a microstrip patch antenna and adopts a symmetrical structure that four corners are cut off by square antenna patches.
The radiation antenna layer of lower floor adopts the microstrip paster antenna of working in 26GHz, adopts the symmetrical formula structure of excision four angles, reduces the antenna paster area occupied, and the symmetrical formula structure is so that microstrip paster is with positive 45 polarization work.
The further technical scheme is as follows: the resonant parasitic antenna unit adopts a high-frequency antenna and works at 39 GHz; the resonance parasitic antenna unit comprises an antenna patch with a square groove dug in the middle and four parasitic patches surrounding the periphery of the antenna patch.
The parasitic antenna layer on the upper layer adopts a high-frequency antenna working at 39GHz, better matching and gain are realized by adopting an antenna patch with a square groove dug in the middle, four parasitic patches are designed around the antenna patch, the isolation can be effectively improved, and the high-frequency bandwidth is widened by a new resonant frequency brought by the parasitic patches.
The further technical scheme is as follows: the parasitic patch operates at 41 GHz.
The high frequency band can be widened by a parasitic patch operating at 41 GHz.
The further technical scheme is as follows: the second dielectric layer and the second metal stratum are also included; the second dielectric layer is arranged at the lower part of the first metal stratum, and the second metal stratum is arranged at the lower part of the second dielectric layer; a metalized through hole is formed in the second medium layer; the second metal stratum is used for welding a test joint, and the test joint is used for connecting test equipment; one end of the feed column is connected with the multi-frequency resonance antenna unit and sequentially penetrates through the first metal stratum and the second dielectric layer, and the other end of the feed column is connected with a welding position of the test joint on the second metal stratum.
The second dielectric layer and the second metal layer are added, so that the structure of the first metal layer is not affected when the array antenna is connected with the test equipment, the metallized through hole is formed in the second dielectric layer, the first metal layer is in good contact with the structure of the second metal layer, and the microstrip antenna can be guaranteed to have a complete radiation grounding plate.
Detailed Description
Example (b): the mutual coupling and interference among the antenna units in the dual-frequency dual-polarization millimeter wave array antenna system cause the performance reduction of the antenna array, and the design requirements for meeting the antennas of different frequency bands are specifically embodied as follows: (1) due to mutual interference among the antenna units, the signal-to-noise ratio is poor, and the data throughput rate is directly influenced; (2) the stronger coupling enables the energy capable of being effectively radiated to be less, thereby causing the gain of the antenna array to be reduced and the energy utilization efficiency to be low; (3) how to realize broadband operation of multiple frequency bands with a small volume; (4) how to implement wide-angle scanning in the case of multi-band dual polarization.
To the above-mentioned demand, this application provides a high isolation dual-frenquency dual-polarization array antenna for millimeter wave frequency channel, combines to refer to fig. 1 to fig. 12, and this a high isolation dual-frenquency dual-polarization array antenna for millimeter wave frequency channel includes from top to bottom in proper order: parasitic antenna layer 1, first dielectric layer 2, radiation antenna layer 3, first metal stratum 4.
The parasitic antenna layer 1 comprises a parasitic antenna array formed by at least one resonant parasitic antenna unit 11.
Optionally, the resonant parasitic antenna unit 11 adopts a high-frequency antenna and works at 39 GHz; the resonant parasitic antenna unit 11 is a microstrip patch antenna, and as shown in fig. 2, the resonant parasitic antenna unit 11 includes an antenna patch 111 with a square slot cut in the middle and four parasitic patches 112 surrounding the antenna patch 111.
As shown in fig. 2, a smaller patch can generate a higher frequency band, the electrical length is 0.22 λ corresponding to 39GHz, and a square groove is dug in the middle of the antenna patch to load a reactance, so that better matching is realized, and the gain of the antenna is improved; the capacitive coupling feed contributes to the widening of the bandwidth, but affects the isolation effect of the dual-polarized port, so that the four parasitic patches 112 are designed around the antenna patch 111, which can effectively improve the isolation and widen the bandwidth.
Optionally, parasitic patch 112 operates at 41GHz, at which 41GHz, parasitic patch 112 has an electrical length of 0.26 λ. The new resonant frequency brought in by the parasitic patch 112 widens the high frequency bandwidth.
The radiation antenna layer 3 includes a radiation antenna array composed of at least one multi-frequency resonance antenna unit 31, and a decoupling structure is disposed between two adjacent multi-frequency resonance antenna units 31.
Optionally, the multi-frequency resonant antenna unit 31 is a low-frequency antenna, and operates at 26 GHz; as shown in fig. 3, the multi-frequency resonant antenna unit 31 is a microstrip patch antenna, and has a symmetric structure in which four corners are cut off by a square antenna patch.
As shown in fig. 3, the larger patch can generate a lower frequency band, the electrical length at 26GHz is 0.27 λ, the four corners of the square patch are cut off to reduce the area occupied by the antenna unit and change the resonant frequency, and the microstrip patch adopts a symmetrical structure so as to operate with positive and negative 45 ° polarization.
The upper layer antenna works at 39GHz, the lower layer antenna works at 26GHz, and the stacked structure of the double-layer antenna meets the requirement of double frequency and reduces the size of the antenna at the same time.
Alternatively, as shown in fig. 4, the decoupling structure includes an I-shaped resonator 32 disposed between two adjacent multi-frequency resonant antenna elements 31 on the radiation antenna layer 3 and a C-shaped circular groove 41 etched on the first metal layer 4.
The C-shaped annular groove 41 etched in the first metal ground layer 4 is equivalent to a band elimination filter, and can also be equivalent to an LC resonance loop shown in fig. 5, and the reactance of the equivalent band elimination filter can be changed and the isolation between the multi-frequency resonance antenna units 31 can be improved by adjusting the size, position and shape of the C-shaped annular groove 41; the I-shaped resonators 32 are disposed between the multi-frequency resonant antenna units 31, so that the isolation between the multi-frequency resonant antenna units 31 can be further improved, and the coupling currents between the multi-frequency resonant antenna units 31 are offset and approach to zero by changing the size and the position of the I-shaped resonators 32, thereby improving the isolation between the multi-frequency resonant antenna units 31. The two decoupling structures are not only suitable for low-frequency structures and specific array antennas, but also can achieve the decoupling effect of different antenna arrays in different frequency bands by adjusting the positions, sizes and shapes of the two decoupling structures, and the decoupling effect is remarkably improved through testing.
In addition, before the I-shaped resonator is not added, the two antenna units are coupled at the edge, after the I-shaped resonator 32 is introduced, the coupling current of the antenna unit is approximately in phase equality with the adjacent antenna unit, and the coupling current approaches zero due to the fact that the I-shaped resonator 32 introduces an additional coupling path with 180-degree phase shift, so that the coupling degree of the two antenna units is further improved, and the coupling between the two antenna units is eliminated.
The first dielectric layer 2 is a dielectric substrate between the resonant parasitic antenna element 11 and the multi-frequency resonant antenna element 31. The first dielectric layer 2 is used for simulating the bonding thickness of the dielectric substrate between the two layers of antennas in the manufacturing process.
The first metal layer 4 is provided with a feeding port 42, and the feeding port 42 is connected with the corresponding multi-frequency resonant antenna unit 31 through a feeding column 5.
Optionally, the multi-frequency resonant antenna unit 31 adopts capacitive feeding, and the feeding port 42 is disposed on a metal ground, and is used for canceling the inductance of the coaxial probe, and widening the bandwidth of the antenna in two frequency bands; illustratively, the multi-frequency resonant antenna unit 31 employs two capacitive feed ports for achieving plus and minus 45 ° polarization.
Optionally, in consideration of various factors in processing, since the SMPM connector used in the test may affect the structure of the metal ground, a layer of dielectric substrate and a metal ground are added on the basis of the array antenna shown in fig. 1, as shown in fig. 6, the high-isolation dual-frequency dual-polarization array antenna for the millimeter wave frequency band further includes a second dielectric layer 6 and a second metal ground layer 7.
The second dielectric layer 6 is arranged at the lower part of the first metal ground layer 4, and the second metal ground layer 7 is arranged at the lower part of the second dielectric layer 6.
The second dielectric layer 6 is provided with a metalized through hole 61. To ensure that the microstrip antenna has a complete radiating ground plane, a double-layer ground structure with metallized vias 61 is designed.
The second metal ground layer 7 is used for welding test joints for connecting test equipment.
One end of the feed column 5 is connected with the multi-frequency resonance antenna unit 31, sequentially penetrates through the first metal stratum 4 and the second dielectric layer 6, and the other end of the feed column is connected with a welding position of the test joint on the second metal stratum 7.
Illustratively, an adhesive layer 8 is disposed between the radiation antenna layer 3 and the first metal ground layer 4 for bonding the upper and lower layers together, although not shown in the figure, in practical application, the first dielectric layer 2 is formed by bonding a dielectric substrate supporting the parasitic antenna layer 1 and a dielectric substrate supporting the radiation antenna layer 3; correspondingly, an adhesive layer is arranged between the first metal ground layer 4 and the second medium layer 6 for adhesion, and an adhesive layer is arranged between the second medium layer 6 and the second metal ground layer 7 for adhesion.
Through tests, the simulation result of the simulated matching and isolation of the array antenna shown in fig. 6 is shown in fig. 7 and fig. 8, the result of the actual measurement of the matching and isolation is shown in fig. 9 and fig. 10, the matching and isolation of the antenna array both meet the basic use requirements, and the shape, size, dimension and position of the multi-frequency resonant antenna unit and the position, shape and dimension of the parasitic antenna structure are adjusted according to the working state of each antenna in the original multi-frequency multi-antenna system, so that the working frequency band and the working bandwidth of each antenna can be changed. Fig. 11 and 12 are beam scanning diagrams of the dual-frequency dual-polarization millimeter wave array antenna shown in the present application at 26GHz and 39GHz, respectively, and it can be seen that the antenna array can achieve ± 60 ° beam scanning at 26GHz and ± 45 ° beam scanning at 39 GHz.
Therefore, the high-isolation dual-frequency dual-polarized array antenna for the millimeter wave frequency band obtains a dual-frequency effect in a stacking mode, the wide bandwidth is widened through the parasitic structure and the capacitive feed structure, and the dual-frequency dual-polarized array antenna can be used for manufacturing products and systems such as intelligent mobile terminals and wireless routers.
To sum up, the high isolation dual-frequency dual-polarized array antenna for the millimeter wave frequency band provided by the application meets the requirement of dual-frequency and reduces the size of the antenna through the stacked structure of the dual-layer antenna, and a decoupling structure is arranged between two adjacent multi-frequency resonant antenna units, so that the coupling of a multi-frequency multi-antenna system with limited space is reduced, and the working performance of the original antenna array is kept.
In addition, a C-shaped annular groove is etched on the first metal ground layer to form the equivalent band elimination filter, the reactive resistance of the equivalent band elimination filter can be changed by adjusting the size and the position of the C-shaped annular groove, the isolation degree between the antenna units is improved, an I-shaped resonator is arranged between two adjacent multi-frequency resonance antenna units, the coupling currents between the antenna units are mutually offset by changing the size and the position of the I-shaped resonator, and therefore the isolation degree between the antenna units is improved.
In addition, the radiation antenna layer of the lower layer adopts a microstrip patch antenna working at 26GHz, and a symmetrical structure with four corners cut off is adopted, so that the occupied area of the antenna patch is reduced, and the microstrip patch can conveniently work in positive and negative 45-degree polarization by the symmetrical structure.
In addition, the parasitic antenna layer on the upper layer adopts a high-frequency antenna working at 39GHz, better matching and gain are realized by adopting an antenna patch with a square groove dug in the middle, four parasitic patches are designed around the antenna patch, the isolation can be effectively improved, and the high-frequency bandwidth is widened by the new resonance frequency brought by the parasitic patches.
In addition, the high frequency band can be widened by the parasitic patch operating at 41 GHz.
In addition, the second dielectric layer and the second metal layer are added, so that the structure of the first metal layer is not affected when the array antenna is connected with the test equipment, the second dielectric layer is provided with the metalized through hole, the first metal layer is in good contact with the structure of the second metal layer, and the microstrip antenna can be guaranteed to have a complete radiation grounding plate.
The terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implying a number of the indicated technical features. Thus, a defined feature of "first", "second", may explicitly or implicitly include one or more of that feature. In the description of the present application, "a plurality" means two or more unless otherwise specified.
The above-mentioned serial numbers of the embodiments of the present application are merely for description and do not represent the merits of the embodiments.
The above description is only exemplary of the present application and should not be taken as limiting the present application, as any modification, equivalent replacement, or improvement made within the spirit and principle of the present application should be included in the protection scope of the present application.