CN103682678A - Dual-polarized base station antenna with Y-feed unit - Google Patents

Abstract

The invention discloses a dual-polarized base station antenna with a Y-shaped feed unit, which comprises a dielectric substrate, a metal reflecting plate, a first coaxial line and a second coaxial line, wherein metal flanges are arranged on two sides of the metal reflecting plate; the first coaxial line is respectively connected with the second annular radiation unit and the first Y-shaped feed unit, and the second coaxial line is respectively connected with the fourth annular radiation unit and the second Y-shaped feed unit. The dual-polarized base station antenna has the advantages of good performance, simple structure, convenient processing, low processing cost and convenient adjustment.

Description

Dual-polarized base station antenna with Y-feed unit

technical field

The invention relates to a base station antenna, in particular to a dual-polarization base station antenna with a Y-shaped feed unit, belonging to the technical field of mobile communication antennas.

Background technique

In the cellular mobile communication system, the base station antenna is the converter of the electrical signal of the communication equipment and the space radiated electromagnetic wave. It plays a pivotal role in the entire communication system, and its performance will directly affect the overall performance of the entire system. Through the intermediary function of the base station antenna, the coverage of the mobile communication network is wider, the communication capacity is larger, the rate is higher, and the service items are more abundant, and the existence of the base station antenna reduces the radiation power of the mobile station antenna, effectively protecting the The human body is protected from strong electromagnetic radiation.

With the continuous development of communication technology, mobile communication is about to enter the fourth generation mobile communication network (4G network). Under the new-generation mobile communication system, various communication standards require mobile communication antennas to be shared by multiple systems to save site installation resources for base stations and reduce network construction costs. At this stage, the market needs a base station antenna with a frequency coverage of 1710MHz-2690MHz, with a bandwidth of 44.5%, and requires stable broadband characteristics in various indicators, such as impedance matching broadband (VSWR<1.5), radiation pattern broadband (The half-power lobe width satisfies 65°±5°), gain, isolation, front-to-back ratio, cross-polarization ratio, etc., which pose new challenges to the design of base station antennas. At the same time, the cost control and simple structure of the base station antenna are also very important. Usually, the printed antenna is easy to process and its cost is relatively low. If it can be used in the design of the base station antenna, it will be a good choice.

According to the investigation and understanding, the currently disclosed prior art is as follows:

1) In 2009, Kwai-Man Luk et al. published an article titled "A Broadband Dual-Polarized Magneto-Electric Dipole Antenna With Simple Feeds" on IEEE ANTENNAS AND WIRELESSPROPAGATION LETTERS, which was realized by using a "Γ"-shaped feed structure Very wide impedance matching, and the introduction of the concept of magnetoelectric dipoles to achieve a broadband pattern.

2) In 2012, Zengdi Bao et al. published an article entitled "A Broadband Dual-Polarization Antena Element for Wireless Communication Base station" at the IEEE Asia-Pacific Conference on Antennas and Propagation, which introduced a balun to achieve a wide range of impedance matching.

3) In 2013, Qing-Xin Chu et al. published an article entitled "A Broadband Unidirectional Multi-dipole Antena with Very Stable Beamwidth" on IEEE TRANSACTIONS ON ANTENNAS ANDPROPAGATION. In this antenna, two different lengths at different heights The dipole antenna achieves a wide impedance broadband, and the E-plane and H-plane radiation patterns are very stable.

However, the above-mentioned prior art still has the problems of complex antenna structure, high processing difficulty and high processing cost, and it is troublesome to adjust, so it is difficult to meet people's needs.

Contents of the invention

The object of the present invention is to solve the above-mentioned defects of the prior art, and provide a dual-polarization base station antenna with a Y-shaped feed unit that is simple in structure, convenient in processing, low in processing cost, and easy to adjust.

The purpose of the present invention can be achieved by taking the following technical solutions:

A dual-polarized base station antenna with a Y-shaped feed unit, including a dielectric substrate and a metal reflector disposed below the dielectric substrate, is characterized in that it also includes a first coaxial line and a second coaxial line for transmitting signals, so The lower surface of the dielectric substrate is provided with a first annular radiation unit, a second annular radiation unit, a third annular radiation unit and a fourth annular radiation unit, and the first annular radiation unit and the second annular radiation unit are symmetrical to each other to form a first In the antenna structure, the third ring-shaped radiation unit and the fourth ring-shaped radiation unit are symmetrical to each other to form a second antenna structure, and the first antenna structure and the second antenna structure are orthogonal to each other to form a dual-polarized antenna structure; the dielectric substrate The upper surface is provided with a first Y-shaped feed unit for feeding the first antenna structure and a second Y-shaped feed unit for feeding the second antenna structure; The radiation unit is connected to the first Y-shaped feed unit, and the second coaxial line is respectively connected to the fourth ring-shaped radiation unit and the second Y-shaped feed unit.

As a preferred solution, the first Y-shaped feed unit includes a first branch part, a first extension part and a second extension part connected in sequence, and the second Y-shaped feed unit includes a second branch part connected in sequence. A fork and a third extension; the first fork is used to couple and excite the first annular radiation unit, and the second fork is used to couple and excite the third annular radiation unit.

As a preferred solution, the dielectric substrate is provided with a first opening and a second opening, and the lower surface of the dielectric substrate is also provided with a fixing unit; one end of the fixing unit passes through the dielectric substrate through the first probe The first opening on the substrate is connected to the first extension part, and the other end is connected to the second extension part after passing through the second opening on the dielectric substrate through the second probe.

As a preferred solution, the dielectric substrate is provided with a third opening and a fourth opening, the outer conductor of the first coaxial line is welded to the second annular radiation unit, and the inner conductor passes through the third hole on the dielectric substrate. After opening the hole, it is welded with the second extension part; the outer conductor of the second coaxial line is welded with the fourth annular radiation unit, and the inner conductor is welded with the third extension part after passing through the fourth opening on the dielectric substrate .

As a preferred solution, both the first coaxial line and the second coaxial line use a coaxial line with an impedance of 50Ω.

As a preferred solution, both sides of the metal reflector are provided with metal flanges perpendicular to the metal reflector.

Compared with the prior art, the present invention has the following beneficial effects:

1. The dual-polarized base station antenna of the present invention has good performance, simple structure, convenient processing, and low processing cost. Two antenna structures are symmetrically formed by four ring-shaped radiation units on the lower surface of the dielectric substrate. When one antenna structure is working, Another antenna structure orthogonal to the antenna structure is used as the load of the antenna structure, thereby saving materials and reducing costs, without adding additional components as load to achieve impedance matching.

2. The dual-polarized base station antenna of the present invention can not only be used to adjust impedance matching (especially impedance matching at high frequencies) very conveniently through two Y-shaped feed units on the upper surface of the dielectric substrate, but also can be used with four loops The radiating elements work together to radiate electromagnetic waves synergistically, realizing a stable bandwidth of the antenna pattern.

3. The dual-polarized base station antenna of the present invention has two resonance points in the required frequency band, and the two resonance frequencies are determined by the lengths of four ring-shaped radiation units and two Y-shaped feed units respectively, so the two The resonance point can be adjusted independently, and a wide impedance bandwidth can be achieved by combining the two resonance points by rationally adjusting the size of the antenna.

4. The layout of the dual-polarized base station antenna of the present invention is reasonable, four annular radiation units are distributed on the lower surface of the dielectric substrate, and two Y-shaped feed units are distributed on the upper surface of the dielectric substrate, so that the two Y-shaped feed units are both It can adjust impedance matching and participate in radiation.

Description of drawings

FIG. 1 is a schematic diagram of a three-dimensional structure of a dual-polarized base station antenna according to Embodiment 1 of the present invention.

FIG. 2 is a three-dimensional structural schematic diagram of the welding of the loop radiation unit, the feed unit and the coaxial line in the dual-polarized base station antenna according to Embodiment 1 of the present invention.

FIG. 3 is a schematic diagram of the structure of the lower surface of the dielectric substrate in the dual-polarized base station antenna according to Embodiment 1 of the present invention.

FIG. 4 is a schematic diagram of the upper surface structure of the dielectric substrate in the dual-polarized base station antenna according to Embodiment 1 of the present invention.

FIG. 5 is an electromagnetic simulation curve diagram of S parameters when the dual-polarized base station antenna according to Embodiment 1 of the present invention works in the 1.71GHz-2.69GHz frequency band.

FIG. 6 is an electromagnetic simulation graph of S parameters when the dual-polarized base station antenna according to Embodiment 1 of the present invention works in the 790MHz-960MHz frequency band.

FIG. 7 is an electromagnetic simulation graph of the standing wave ratio when the dual-polarized base station antenna according to Embodiment 1 of the present invention works in the 1.71GHz-2.69GHz frequency band.

FIG. 8 is an electromagnetic simulation graph of the standing wave ratio when the dual-polarization base station antenna according to Embodiment 1 of the present invention works in the 790MHz-960MHz frequency band.

FIG. 9 is an electromagnetic simulation graph of the half-power lobe width in the horizontal plane when the dual-polarized base station antenna according to Embodiment 1 of the present invention works in the 1.71 GHz-2.69 GHz frequency band.

FIG. 10 is an electromagnetic simulation graph of the half-power lobe width in the horizontal plane when the dual-polarized base station antenna according to Embodiment 1 of the present invention works in the 790MHz-960MHz frequency band.

FIG. 11 is an electromagnetic simulation curve diagram of gain when the dual-polarization base station antenna of Embodiment 1 of the present invention works in the 1.71GHz-2.69GHz frequency band.

FIG. 12 is an electromagnetic simulation curve diagram of gain when the dual-polarized base station antenna according to Embodiment 1 of the present invention works in the 790MHz-960MHz frequency band.

Fig. 13 is a three-dimensional schematic diagram of the welding of the loop radiation unit, the feed unit and the coaxial line in the dual-polarized base station antenna according to Embodiment 2 of the present invention.

Among them, 1-dielectric substrate, 2-metal reflector, 3-first coaxial line, 4-second coaxial line, 5-metal flange, 6-first annular radiation unit, 7-second annular radiation unit, 71-the first circular part, 8-the third circular radiation unit, 9-the fourth circular radiation unit, 91-the second circular part, 10-fixed unit, 11-the first Y-shaped feed unit, 111-the first A bifurcation part, 112-the first extension part, 113-the second extension part, 12-the second Y-shaped feed unit, 121-the second bifurcation part, 122-the third extension part, 13-the first opening , 14-second opening, 15-third opening, 16-fourth opening, 17-first probe, 18-second probe.

Detailed ways

Example 1:

As shown in Figures 1-4, the dual-polarized base station antenna of this embodiment includes a dielectric substrate 1, a metal reflector 2, a first coaxial line 3, and a second coaxial line 4, and the metal reflector 2 is arranged on a medium Below the substrate 1, metal flanges 5 perpendicular to the metal reflector 2 are provided on both sides thereof. The metal reflector 2 and the metal flange 5 can be made of different materials such as copper, aluminum, silver, etc. The first coaxial line 3 and the impedance of the second coaxial line 4 are both 50Ω; the lower surface of the dielectric substrate 1 is provided with a first annular radiation unit 6, a second annular radiation unit 7, a third annular radiation unit 8, and a fourth annular radiation unit 9 And the fixing unit 10, the upper surface of the dielectric substrate 1 is provided with a first Y-shaped feed unit 11 and a second Y-shaped feed unit 12, and the dielectric substrate 1 is provided with a first opening 13, a second opening 14. The third opening 15 and the fourth opening 16, wherein:

The first annular radiation unit 6, the second annular radiation unit 7, the third annular radiation unit 8, and the fourth annular radiation unit 9 are all adjusted to a hexagonal structure, and the first annular radiation unit 6 and the second annular radiation unit The radiating units 7 are symmetrical to each other to form a first antenna structure, the third annular radiating unit 8 and the fourth annular radiating unit 9 are symmetrical to each other to form a second antenna structure, and the first antenna structure and the second antenna structure are orthogonal to each other to form a double antenna structure. Polarized antenna structure, due to feeding needs, the second circular radiation unit 7 digs out the first circular part 71, and the first circular part 71 makes the second circular radiation unit 7 and the outer conductor of the first coaxial line 3 phase welding; the fourth annular radiation unit 9 cuts out the second circular portion 91 , and the second circular portion 91 makes the fourth annular radiation unit 9 and the outer conductor of the second coaxial line 4 welded.

The first Y-shaped feed unit 11 is used to feed the first antenna structure, including a first bifurcated portion 111, a first extension portion 112 and a second extension portion 113, and the inner conductor of the first coaxial line 3 After passing through the third opening 15 on the dielectric substrate 1, it is welded to the second extension part 113; one end of the fixing unit 10 passes through the first opening 13 on the dielectric substrate 1 through the first probe 17 and is connected to the second extension part 113. One extension part 112 is connected, and the other end is connected to the second extension part 113 after passing through the second opening 14 on the dielectric substrate 1 through the second probe 18, so that the first Y-shaped feed unit 11 is not connected to the second Y-shaped feed unit 11. The feeding units 12 are overlapped; the first bifurcated part 111 is connected to the first extending part 112 , and the first ring-shaped radiation unit 6 is coupled and excited through the first bifurcated part 111 .

The second Y-shaped feed unit 12 is used to feed the second antenna structure, including a second bifurcated portion 121 and a third extension portion 122, and the inner conductor of the second coaxial line 4 passes through the dielectric substrate 1 The fourth opening 16 on the top is welded with the third extension part 122 , the second branch part 121 is connected with the third extension part 122 , and the third annular radiation unit 8 is coupled and excited through the second branch part 121 .

As shown in Figure 5, it is the S-parameter electromagnetic simulation curve (S11 refers to the return loss of input port 1, and S22 refers to the return loss of output port 2) of the dual-polarized base station antenna of the present embodiment working in the 1.71GHz-2.69GHz frequency band , S12 refers to the reverse transmission coefficient, that is, isolation), and a resonance point appears at the frequency of 1.8GHz and 2.55GHz respectively. The resonance frequency at the low frequency is determined by the length of the four ring-shaped radiation units. The longer it is, the more it moves to the low frequency direction. ; while the resonant frequency at the high frequency is determined by the length of the two Y-shaped feed units, the longer it is, the more it moves towards the low-frequency direction; by reasonably adjusting the lengths of the four ring-shaped radiation units and the lengths of the two Y-shaped feed units , so that the low frequency and high frequency have achieved a good match, so as to achieve a wide impedance bandwidth, and the isolation has reached more than 27dB.

As shown in Figure 6, it is the S-parameter electromagnetic simulation curve (S11 refers to the return loss of the input port 1, S22 refers to the return loss of the output port 2, when the dual-polarized base station antenna of the present embodiment works in the 790MHz-960MHz frequency band, S12 refers to the reverse transmission coefficient, that is, isolation), and there is a resonance point at 800MHz and 1060MHz respectively. By reasonably adjusting the lengths of the four ring-shaped radiation units and the lengths of the two Y-shaped feed units, the low-frequency and The high frequency has achieved a good match, so as to achieve a wide impedance bandwidth, and the isolation has reached more than 30dB.

As shown in Fig. 7 and Fig. 8, it is respectively the standing wave ratio electromagnetic simulation curve (Port1 refers to the standing wave of input port 1) when the dual-polarized base station antenna of the present embodiment works in the 1.71GHz-2.69GHz frequency band and the 790MHz-960MHz frequency band Ratio, Port2 refers to the standing wave ratio of the output port 2), it can be seen that in the two frequency bands, the standing wave ratio is less than 1.5 and less than 1.4 respectively. In addition, through the synergy of four ring radiation units and two Y-shaped feed units, The antenna radiation pattern is also very stable.

As shown in Fig. 9 and Fig. 10, it is the horizontal plane half-power lobe width electromagnetic simulation curve (Port1 refers to the input port 1 The horizontal plane half power lobe width of , Port2 refers to the horizontal plane half power lobe width of output port 2), it can be seen that in the two frequency bands, the horizontal plane half power lobe width is within the range of 65°±5°.

As shown in Fig. 11 and Fig. 12, it is the electromagnetic simulation curve (Port1 refers to the gain of input port 1, Port2 refers to output The gain of port 2), it can be seen that in the two frequency bands, the gain can reach more than 8dBi.

Example 2:

As shown in Figure 13, the main features of the dual-polarized base station antenna of this embodiment are: the first annular radiation unit 6, the second annular radiation unit 7, the third annular radiation unit 8, and the fourth annular radiation unit 9 are all adjustable It is an octagonal structure, and the first branch portion 111 of the first Y-shaped feed unit 11 and the second branch portion 121 of the second Y-shaped feed unit 12 are shorter than those of the first embodiment. All the other are with embodiment 1.

The above is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto, any person familiar with the technical field within the scope disclosed in the present invention, according to the technical scheme of the present invention and its Any equivalent replacement or change of the inventive concept falls within the protection scope of the present invention.

Claims (6)

1. the Bipolarization antenna for base station with Y shape feed element, comprise medium substrate and the metallic reflection plate that is arranged on medium substrate below, it is characterized in that: also comprise the first coaxial line and the second coaxial line for signal transmission, the lower surface of described medium substrate is provided with the first annular radiating element, the second ring radiation unit, the 3rd ring radiation unit and Fourth Ring shape radiating element, described the first annular radiating element and the second ring radiation unit form first day line structure symmetrically, described the 3rd ring radiation unit and Fourth Ring shape radiating element form second day line structure symmetrically, the mutually orthogonal formation dual-polarized antenna structure of described first day line structure and second day line structure, the upper surface of described medium substrate is provided with for the first Y shape feed element to first day line structure feed and for the second Y shape feed element to second day line structure feed, described the first coaxial line is connected with the first Y shape feed element with the second ring radiation unit respectively, and described the second coaxial line is connected with the second Y shape feed element with Fourth Ring shape radiating element respectively.

2. the Bipolarization antenna for base station with Y shape feed element according to claim 1, it is characterized in that: described the first Y shape feed element comprises the first forked section, the first extension and the second extension being connected successively, and described the second Y shape feed element comprises the second connected forked section and the 3rd extension; Described the first forked section is for the annular radiating element of coupling excitation first, and described the second forked section is for coupling excitation the 3rd ring radiation unit.

3. the Bipolarization antenna for base station with Y shape feed element according to claim 2, is characterized in that: described medium substrate offers the first perforate and the second perforate, and the lower surface of described medium substrate is also provided with fixed cell; One end of described fixed cell is connected with the first extension after passing the first perforate on medium substrate by the first probe, and the other end is connected with the second extension after passing the second perforate on medium substrate by the second probe.

4. the Bipolarization antenna for base station with Y shape feed element according to claim 2, it is characterized in that: described medium substrate offers the 3rd perforate and the 4th perforate, the outer conductor of described the first coaxial line welds mutually with the second ring radiation unit, and inner wire welds with the second extension phase-splitting after passing the 3rd perforate on medium substrate; The outer conductor of described the second coaxial line welds mutually with Fourth Ring shape radiating element, and inner wire welds with the 3rd extension phase-splitting after passing the 4th perforate on medium substrate.

5. the Bipolarization antenna for base station with Y shape feed element according to claim 4, is characterized in that: it is the coaxial line of 50 Ω that described the first coaxial line and the second coaxial line all adopt impedance.

6. the Bipolarization antenna for base station with Y shape feed element according to claim 1, is characterized in that: the both sides of described metallic reflection plate are provided with the metal flange vertical with metallic reflection plate.

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