A fully polarized antenna with full coverage of the upper hemisphere

Abstract

The present invention relates to a fully polarized antenna for covering the upper hemisphere airspace, and belongs to the field of antenna technology. Its structure includes a microstrip antenna, a dipole loop antenna, a monopole antenna, a radome, a metal bottom plate and other parts. The microstrip antenna includes two layers of microstrip circuit boards placed orthogonally, two groups of signal connectors, and square metal patterns are etched on the upper surfaces of the two layers of microstrip circuit boards. The dipole loop antenna includes a microstrip circuit board with a "swastika"-shaped metal pattern etched on the front and back sides, a feeding coaxial line and a feeding signal connector. The monopole antenna includes a hollow copper column, a feeding microstrip circuit board and a feeding signal connector. It can achieve full polarization coverage in the zenith direction and the horizontal direction of the upper hemisphere space, which is of great significance to improving the channel capacity and transmission rate of the communication system.

Description

Technical Field

[0001] The invention relates to a fully polarized antenna for covering an upper hemisphere airspace, which is suitable for receiving multi-polarized channel information in the upper hemisphere airspace and belongs to the technical field of antennas. Background Art

[0002] With the rapid development of wireless communication technology, traditional channel diversity methods such as frequency domain, time domain and code domain have been widely used in mobile communications, satellite communications and other fields. In the environment of limited electromagnetic spectrum resources, polarization diversity technology is of great significance to further improve the channel capacity and transmission rate of communication systems. Dual-polarized antennas only support polarization coverage requirements within a limited direction and are difficult to apply to wide-angle polarization diversity communication applications. While providing signal coverage for airspace outside the limited direction, tri-polarized antennas fail to provide polarization coverage in the gain coverage area. Summary of the invention

[0003] In view of the fact that the current three-polarized antenna cannot achieve full polarization coverage in the gain coverage area, the present invention proposes a fully polarized antenna with full upper hemisphere coverage. The antenna divides the upper hemisphere into two parts, the zenith direction and the horizontal direction, and covers two orthogonal polarizations in the two airspaces to achieve full polarization coverage of the upper hemisphere.

[0004] To achieve the above object, the present invention adopts the following technical solutions:

[0005] The fully polarized antenna with full upper hemisphere coverage includes a microstrip antenna 1, a dipole loop antenna 2, a monopole antenna 3, a radome 4, and a metal base plate 5;

[0006] The microstrip antenna 1 comprises two layers of microstrip circuit boards placed orthogonally, and two groups of signal connectors. Square metal patterns are etched on the upper surfaces of the two layers of microstrip circuit boards. The signal connectors are connected to the square metal patterns on the bottom microstrip board, and the connectors are defined as X ports and Y ports respectively.

[0007] The dipole loop antenna 2 includes a top microstrip circuit board, a feeding coaxial line and a feeding signal connector. A swastika-shaped metal pattern is etched on the front and back of the microstrip circuit board. The coaxial line extending from the center of the monopole antenna is fed. The feeding position is located at the center of the metal pattern. The feeding signal connector is defined as an H port.

[0008] The monopole antenna 3 includes a hollow copper column, a feeding microstrip circuit board and a feeding signal connector. The hollow part is used to pass the feeding coaxial line of the dipole ring antenna 2. The feeding microstrip circuit board is located above the metal bottom plate 5. The monopole antenna 3 is fed through a one-to-two feeding network. The feeding signal connector is defined as a V port.

[0009] The radome 4 includes a nylon dielectric frame and threaded holes for fixing, and is fixedly connected to the dipole loop antenna 2 and the metal base plate 5 by screws, which is used to support the overall antenna and provide structural stability.

[0010] The metal base plate 5 is made of aluminum alloy material, and its outer surface is subjected to original color conductive oxidation treatment to play a better protective role. It is used to carry the feeding joints of the microstrip antenna 1, the monopole antenna 3, and the dipole loop antenna 2, and to realize the grounding of the antenna.

[0011] The installation process of the full-polarization antenna with the upper hemisphere fully covered is as follows:

[0012] Install the feeding network circuit board of the monopole antenna 3 on the metal floor 5, and fix the four corners with metal screws. Fix the feeding joints of the microstrip antennas 1 and the monopole antenna 3 to the bottom of the metal floor with metal screws. Weld the monopole antenna 3 to the feeding network. Then install the microstrip antenna 1 above the feeding network circuit board of the monopole antenna 3, and the central through hole passes through the monopole antenna 3. The two-layer microstrip antennas 1 are air-lifted by the dielectric columns at the four corners. The feeding coaxial cable of the dipole loop antenna 2 passes through the center of the hollow copper column of the monopole antenna 3. The inner conductor of the feeding coaxial cable is welded to the upper pattern of the dipole loop antenna 2, and the outer conductor is welded to the lower pattern of the dipole loop antenna 2. The radome 5 is connected to the metal floor 4 and the dipole antenna 2 with metal screws.

[0013] The microstrip antenna 1 radiates dual-polarized electromagnetic waves, which is used to realize the coverage of two orthogonal polarizations in the zenith direction.

[0014] The dipole loop antenna 2 radiates horizontally omnidirectional horizontally polarized electromagnetic waves, which is used to realize the coverage of horizontal polarization in the horizontal direction.

[0015] The monopole antenna 3 radiates horizontally omnidirectional vertically polarized electromagnetic waves, which is used to realize the coverage of vertical polarization in the horizontal direction.

[0016] The working process of the full-polarization antenna with the upper hemisphere fully covered in the present invention is as follows:

[0017] Connect the full-polarization antenna with the upper hemisphere fully covered in the present invention to the transmitting system, feed RF signals into the feeding ports of each antenna, and emit electromagnetic waves of different polarizations through the three antennas to realize the emission of any polarized electromagnetic wave signals in the upper hemisphere. Connect the full-polarization antenna with the upper hemisphere fully covered in the present invention to the receiving system, receive electromagnetic waves of different polarizations from the space of the upper hemisphere through the three antennas, and transmit signals to the receiving system through the feeding ports of each antenna to realize the reception of different polarized electromagnetic wave signals.

[0018] The operating frequency bands of the microstrip antenna 1, dipole loop antenna 2, and monopole antenna 3 are all located in the S band.

[0019] Beneficial effects

[0020] The all-polarization antenna with full coverage of the upper hemisphere according to the present invention has the following beneficial effects compared with the existing triple-polarization antenna;

[0021] 1. Large coverage angle, realizing full-polarization radiation at any angle in the upper hemisphere;

[0022] 2. Multiple ports, forming multi-port coverage in some airspaces, which can be used to reconstruct the antenna pattern;

[0023] 3. The function of reconstructing the pattern can be used to reduce the array side lobes at specific angles;

[0024] 4. It is possible to synthesize arbitrary-angle and arbitrary-polarization radiation on the upper hemisphere;

[0025] 5. It is possible to restore the polarization of electromagnetic waves with unknown polarization on the upper hemisphere. Description of the drawings

[0026] Figure 1 is the division of the upper half-space airspace of the all-polarization antenna in the embodiment of the present invention;

[0027] Figure 2 is the overall structural schematic diagram of the all-polarization antenna in the embodiment of the present invention;

[0028] Figure 3 is the schematic diagram of the composition structure of the all-polarization antenna in the embodiment of the present invention, where Figure 3 (a) is the schematic diagram of the dipole loop antenna, Figure 3 (b) is the schematic diagram of the microstrip antenna, Figure 3 (c) is the schematic diagram of the monopole antenna;

[0029] Figure 4 is the return loss curve of the all-polarization antenna in the embodiment of the present invention;

[0030] Figure 5 is the port isolation curve of the all-polarization antenna in the embodiment of the present invention;

[0031] Figure 6 is the normalized pattern of the main polarization and cross polarization of the X port of the all-polarization antenna in the embodiment of the present invention;

[0032] Figure 7 is the normalized pattern of the main polarization and cross polarization of the Y port of the all-polarization antenna in the embodiment of the present invention;

[0033] Figure 8 is the normalized pattern of the independent radiation of the H port of the all-polarization antenna in the embodiment of the present invention, whereFigure 8 (a) Yes The normalized radiation pattern of Figure 8 (b) is the normalized radiation pattern when θ = 90°;

[0034] Figure 9 is the normalized radiation pattern of the independent V-port of the fully polarized antenna of the embodiment of the present invention, wherein Figure 9 (a) Yes The normalized radiation pattern of Figure 9 (b) is the normalized radiation pattern when θ = 90°; DETAILED DESCRIPTION

[0035] In order to better illustrate the purpose and advantages of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments.

[0036] Example

[0037] The structure of this embodiment is as follows Figure 2 This example includes a microstrip antenna 1, a dipole loop antenna 2, a monopole antenna 3, a radome 4, and a metal base plate 5;

[0038] The microstrip antenna 1 includes two layers of microstrip circuit boards placed orthogonally, two groups of signal connectors, and square metal patterns are etched on the upper surface of the two layers of microstrip circuit boards. The two layers of microstrip circuit boards are elevated by air using dielectric columns at the four corners, and the thickness of the air layer is 2mm. The dimensions of the two layers of dielectric substrates are 50mm×50mm×2mm, the side length of the lower square patch is 32mm, and the side length of the upper square patch is 36mm. The signal connector is connected to the square metal pattern on the bottom microstrip board, and the connectors are defined as X port and Y port respectively;

[0039] The dipole loop antenna 2 includes a top microstrip circuit board, a feeding coaxial line and a feeding signal connector. The size of the microstrip circuit board is 62mm×62mm×1mm, and a swastika-shaped metal pattern is etched on the front and back sides. The feeding position is located at the center of the metal pattern. The inner conductor of the coaxial line extending from the center of the monopole antenna 3 is welded to the center of the upper surface of the pattern, and the outer conductor of the coaxial line is welded to the center of the lower surface of the pattern for feeding. It is connected to the radiation arm of the dipole loop antenna 2 through a cross-shaped metal feed line divided into four with a width of 0.8mm, and the end of the feed line is widened to adjust the impedance;

[0040] The monopole antenna 3 includes a hollow copper column, a feeding microstrip circuit board and a feeding signal connector. The outer diameter of the hollow copper column is 7 mm and the height is 32 mm. The hollow part is used to pass the feeding coaxial line of the dipole ring antenna 2. The feeding microstrip circuit board is located above the metal bottom plate 5 and feeds the monopole antenna 3 through a one-to-two feeding network;

[0041] In the all-polarization antenna with the upper hemisphere surface fully covered, the radome 4 includes a nylon dielectric frame and threaded holes required for fixing, and is connected to the dipole loop antenna 2 and the metal base plate 5 by screws to support the overall antenna;

[0042] The metal base plate 5 is made of aluminum alloy material, and its outer surface is subjected to primary color conductive oxidation treatment to play a better protective role. It is used to carry the feed joints of the microstrip antenna 1, the monopole antenna 3, and the dipole loop antenna 2, and to realize the grounding of the antenna;

[0043] The overall size of this embodiment is 62mm×62mm×42mm.

[0044] Figure 4 This is the test result of the return loss of this embodiment. The working frequency band of the X port covers 2.33 - 2.50GHz, and the relative bandwidth is 7.1%. The working frequency band of the Y port covers 2.34 - 2.51GHz, and the relative bandwidth is 7.1%. The working frequency band of the H port covers 2.35 - 2.54GHz, and the relative bandwidth is 7.9%. The working frequency band of the V port covers 2.36 - 2.46GHz, and the relative bandwidth is 4.2%.

[0045] Figure 5 This is the test result of the port isolation of this embodiment. In the frequency band of 2.2 - 2.6GHz, the mutual coupling between each port is less than -23dB.

[0046] The antenna made in this embodiment is tested in an anechoic chamber, and the measured results are as Figures 6 to 9 shown. It can be seen from this that when the X port is excited, the cross polarization is lower than -20.8dB. When the Y port is excited, the cross polarization is lower than -21.5dB. When the H port is excited, the cross polarization is lower than -22.8dB. When the V port is excited, the cross polarization is lower than -14.3dB.

[0047] The above is only the preferred embodiment of the present invention. Any equivalent changes and modifications made within the scope of the claims of the present invention shall fall within the scope covered by the claims of the present invention.

Claims

1. A full-polarization antenna with full coverage of the upper hemisphere, characterized in that: The fully polarized antenna comprises a microstrip antenna 1, a dipole loop antenna 2, a monopole antenna 3, a radome 4 and a metal base plate 5; The microstrip antenna 1 comprises two layers of microstrip circuit boards placed orthogonally, and two groups of signal connectors. Square metal patterns are etched on the upper surfaces of the two layers of microstrip circuit boards. The signal connectors are connected to the square metal patterns on the bottom microstrip board, and the connectors are defined as X ports and Y ports respectively. The dipole loop antenna 2 includes a top microstrip circuit board, a feeding coaxial line and a feeding signal connector. A swastika-shaped metal pattern is etched on the front and back of the microstrip circuit board. The coaxial line extending from the center of the monopole antenna is fed. The feeding position is located at the center of the metal pattern. The feeding signal connector is defined as an H port. The monopole antenna 3 includes a hollow copper column, a feeding microstrip circuit board and a feeding signal connector. The hollow part is used to pass the feeding coaxial line of the dipole ring antenna 2. The feeding microstrip circuit board is located above the metal bottom plate 5. The monopole antenna 3 is fed through a one-to-two feeding network. The feeding signal connector is defined as a V port. The antenna cover 4 includes a nylon dielectric frame and threaded holes required for fixing, and is connected and fixed to the dipole ring antenna 2 and the metal base plate 5 by screws, so as to support the antenna as a whole and provide structural stability; The metal base plate 5 is made of aluminum alloy, and its outer surface is treated with primary color conductive oxidation to provide better protection. It is used to carry the feeding connectors of the microstrip antenna 1, the monopole antenna 3, and the dipole loop antenna 2, and to achieve antenna grounding.

2. The all-polarization antenna with full coverage of the upper hemisphere according to claim 1, wherein: The microstrip antenna 1 radiates dual-polarized electromagnetic waves, and is used to achieve coverage of two orthogonal polarizations in the zenith direction.

3. The all-polarization antenna with full coverage of the upper hemisphere according to claim 1, wherein: The dipole ring antenna 2 radiates horizontal omnidirectional horizontally polarized electromagnetic waves, and is used to achieve horizontal polarization coverage in the horizontal direction.

4. The all-polarization antenna with full coverage of the upper hemisphere surface according to claim 1, characterized in that: The monopole antenna 3 radiates horizontal omnidirectional vertically polarized electromagnetic waves, so as to achieve horizontal vertically polarized coverage.

5. The all-polarization antenna with full coverage of the upper hemisphere according to claim 1, characterized in that: The operating frequency bands of the microstrip antenna 1 , the dipole loop antenna 2 , and the monopole antenna 3 are all in the S band.

6. The all-polarization antenna with full coverage of the upper hemisphere according to claim 1, wherein: The fully polarized antenna with full coverage of the upper hemisphere realizes the transmission and reception of electromagnetic wave signals with arbitrary polarization on the upper hemisphere through the cooperation of the microstrip antenna 1, the dipole ring antenna 2 and the monopole antenna 3.

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