High-isolation multi-frequency antenna circuit board and system

Abstract

The utility model discloses a high-isolation multi-frequency antenna circuit board, which comprises a PCB substrate, two LTE antennas and a GNSS antenna are distributed on the PCB substrate, the GNSS antenna is located in the middle of the substrate, the two LTE antennas are respectively arranged at two ends of the substrate, each LTE antenna comprises an antenna radiation network, an antenna resistor and an antenna feed network, and the antenna feed networks are arranged on the back surface of the PCB substrate; and a microstrip radiation isolation sheet for increasing isolation is arranged between the two antennas. And the communication in the frequency band of 698 to 960 MHz and the frequency band of 1710 to 2700 MHz is realized. By adding the resistors in the antennas and changing the radiation unit structure in the radiation network, the electromagnetic coupling between the antennas is changed, the resistance value of the resistors is changed, the isolation between the antennas is adjusted, and the anti-interference intensity between the antennas is enhanced.

Description

Technical Field

[0001] The utility model belongs to the technical field of isolation antennas, and particularly relates to a high-isolation multi-frequency antenna circuit board and system. Background Technique

[0002] Isolation antenna technology means that in a communication system, antennas need to maintain a high degree of isolation to prevent signal interference. In traditional antenna designs, the isolation between antennas is usually low, which can lead to signal interference and a decline in system performance.

[0003] Existing methods for improving the isolation between antennas include spatial isolation, polarization orthogonal isolation, adding obstacles between antennas for isolation, isolator / balun isolation, neutralization network, decoupling network isolation, etc. These methods for improving the isolation between antennas can be implemented based on a sufficient antenna layout structure and the absence of other antennas between the two antennas. In the current environment, the requirement for the integrated distribution of the antenna system is integrated, and the structure is miniaturized, which undoubtedly increases the difficulty of improving the isolation between antennas. Summary of the Invention

[0004] The technical problem to be solved by the utility model is to provide a high-isolation multi-frequency antenna circuit board and system, which solves the problem of the difficulty in improving the isolation between miniaturized antennas in the prior art.

[0005] The utility model adopts the following technical solutions to solve the above technical problems:

[0006] A high-isolation multi-frequency antenna circuit board includes a PCB substrate. Two LTE antennas and a GNSS antenna are distributed on the PCB substrate. The GNSS antenna is located in the middle of the substrate, and the two LTE antennas are respectively arranged at both ends of the substrate. Both of the two LTE antennas include an antenna radiation network, an antenna resistor, and an antenna feeding network. Among them, the antenna feeding network is arranged on the back of the PCB substrate; a microstrip radiation isolation sheet for increasing isolation is provided between the two antennas.

[0007] The two LTE antennas are respectively a main antenna and a sub-antenna; among them, the sub-antenna includes a low-frequency radiation branch, a medium-high frequency radiation branch, and a coupling radiation branch. The coupling radiation branch is arranged at the middle position between the low-frequency and medium-high frequency radiation networks; the main antenna includes a low-frequency and medium-frequency radiation branch, a high-frequency radiation branch, and a coupling radiation branch. The coupling radiation branch is arranged on the back of the PCB substrate.

[0008] The coupling radiation branch of the main antenna is located directly below the low-frequency and medium-frequency radiation branches.

[0009] The sizes of the LTE main antenna and the sub-antenna are both less than 40x30mm.

[0010] The microstrip radiation isolation sheet is arranged on one side of the main antenna and is located between the main antenna and the GNSS antenna.

[0011] The microstrip radiation isolation sheet is arranged at a position close to the edge of the PCB substrate.

[0012] The positions and resistances of the two antenna resistors are changed according to the isolation index between the two antennas.

[0013] The antenna resistor selects a corresponding type according to different application scenarios.

[0014] The antenna resistor selects a chip resistor or a surface mount resistor.

[0015] The covered frequency bands of the LTE antenna include 698 - 960 MHz and 1710 - 2700 MHz.

[0016] The high - isolation multi - frequency antenna system includes the high - isolation multi - frequency antenna circuit board described above.

[0017] Compared with the prior art, the utility model has the following beneficial effects:

[0018] 1. Two LTE antennas and one GNSS antenna are distributed on the PCB substrate, realizing communication within the frequency bands of 698 - 960 MHz and 1710 - 2700 MHz.

[0019] 2. By adding resistors in the antenna, the radiation unit structure (quantity, shape, etc.) in the radiation network is changed, thereby changing the electromagnetic coupling between the antennas. By changing the resistance value of the resistor, the isolation degree between the antennas is adjusted, and the anti - interference strength between the antennas is enhanced.

[0020] 3. By adopting a special antenna design and structure, the isolation degree between the antennas is effectively improved, thus ensuring the normal operation and performance of the communication system. Description of the Drawings

[0021] Figure 1 It is a schematic structural diagram of the high - isolation multi - frequency antenna circuit board of the utility model.

[0022] Figure 2 It is a schematic diagram of the dimensional specifications of an embodiment of the high - isolation multi - frequency antenna circuit board of the utility model.

[0023] Among them, the markings in the figure are: 1. LTE secondary antenna; 2. LTE main antenna; 3. GNSS antenna system; 101, 102, 103, and 104 are the radiation networks of the LTE secondary antenna, where 101 and 103 are both low - frequency radiation branches, 102 is a medium - high - frequency radiation branch, and 104 is the coupling radiation branch of the secondary antenna; 105. LTE secondary antenna resistor; 106. LTE secondary antenna feeding network;

[0024] 201, 202, 203, 204, and 205 are LTE main antenna radiation networks. Among them, 201 and 202 are low-frequency and medium-frequency radiation branches, 203 is a high-frequency radiation branch, 204 is a microstrip radiation isolation sheet of the antenna; 205 is a coupled radiation branch of the main antenna; 206 is the LTE main antenna resistance; 207 is the LTE main antenna feeding network. Detailed implementation manners

[0025] In order to enable those skilled in the art to better understand the solution of this application, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of this application. Obviously, the described embodiments are only a part of the embodiments of this application, rather than all the embodiments.

[0026] Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the scope of protection of this application.

[0027] A high-isolation multi-band antenna circuit board includes a PCB substrate. Two LTE antennas and a GNSS antenna are distributed on the PCB substrate. The GNSS antenna is located in the middle of the substrate, and the two LTE antennas are respectively arranged at both ends of the substrate. Both LTE antennas include an antenna radiation network, an antenna resistance, and an antenna feeding network. Among them, the antenna feeding network is arranged on the back of the PCB substrate; a microstrip radiation isolation sheet for increasing the isolation degree is provided between the two antennas.

[0028] Specific embodiments are as Figure 1 、 Figure 2 shown

[0029] A high-isolation multi-band antenna circuit board includes a PCB substrate. Two LTE antennas and a GNSS antenna 3 are distributed on the PCB substrate. The GNSS antenna is located in the middle of the substrate. The two LTE antennas are respectively the LTE main antenna 2 and the LTE sub-antenna 1, which are arranged at both ends of the substrate. The sub-antenna radiation network includes a low-frequency radiation branch 101, a low-frequency radiation branch 103, a medium-high-frequency radiation branch 102, a coupled radiation branch 104, an LTE sub-antenna resistance 105, and an LTE sub-antenna feeding network 106; the coupled radiation branch 104 is placed in the middle position between the low-frequency (698 - 960 MHz) and medium-high-frequency (1710 - 2700 MHz) radiation networks, interacts with the two frequency bands, and has a coupled influence, playing a role in optimizing the LTE sub-antenna; the LTE sub-antenna feeding network 106 is distributed on the back of the PCB substrate;

[0030] The main antenna radiation network includes a low-frequency radiation branch 201, a medium-frequency radiation branch 202, a high-frequency radiation branch 203, a microstrip radiation isolation sheet 204 of the antenna, a coupled radiation branch 205 of the main antenna, an LTE main antenna resistor 206, and an LTE main antenna feeding network 207; the microstrip radiation isolation sheet 204 is placed below the LTE main antenna 2, affecting the electromagnetic energy field between the two antennas and increasing the isolation degree between the two antennas; the coupled radiation branch 205 of the main antenna is distributed on the back of the PCB substrate, directly below the low-frequency radiation branch 201 and the medium-frequency radiation branch 202, and has a coupled effect, playing a role in optimizing the LTE main antenna; the LTE main antenna feeding network 207 is distributed on the back of the PCB substrate.

[0031] The positions and resistances of the two antenna resistors are changed according to the isolation index between the two antennas.

[0032] The antenna resistor selects a corresponding type according to different application scenarios.

[0033] The antenna resistor selects a chip resistor or a surface mount resistor.

[0034] The covered frequency bands of the LTE antenna include 698 - 960 MHz and 1710 - 2700 MHz.

[0035] In this embodiment, the LTE antenna indicators are shown in Table 1. The antenna standing wave ratio, gain, efficiency, and isolation degree are interrelated. As shown in the example of Table 1, they increase and decrease reciprocally, so a balanced state needs to be achieved.

[0036] Table 1

[0037]

[0038] Both the LTE main and auxiliary antennas use resistors. By adjusting the resistors, various indicators of the LTE antenna can be adjusted, especially the isolation degree between the two antennas. As shown in the appendix Figure 1 In the LTE auxiliary antenna resistor 105 and the LTE main antenna resistor 206, the positions and resistances of the two resistors can be changed. By adding resistors to the antenna, the radiation unit structure (quantity, shape, etc.) in the radiation network is changed, thereby changing the electromagnetic coupling between the antennas, so as to achieve the purpose of changing the isolation degree. Of course, different types of resistors, such as chip resistors, surface mount resistors, etc., can also be selected to adapt to different application scenarios.

[0039] Through the comprehensive adjustment of the circuit structures of this solution, the sizes of both the LTE main antenna and the auxiliary antenna can achieve a specification of less than 40x30 mm.

[0040] In this embodiment, the PCB substrate is a double-sided board, designed with a rigid PCB, and the size is: 100x40x1 mm.

[0041] The present application also discloses a high-isolation multi-frequency antenna system. According to different system requirements, the high-isolation multi-frequency antenna circuit board with different parameters can be selected.

[0042] What the present application aims to protect is the high-isolation multi-frequency antenna circuit device, its circuit connection relationship, and the arrangement relationship of each component on the circuit board. The content protected by the present application does not involve improvements to software and methods either.

[0043] The above are only the preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included within the protection scope of the present application.

Claims

1. A high isolation multi-frequency antenna circuit board, characterized in that: It includes a PCB substrate, on which two LTE antennas and one GNSS antenna are distributed, the PCB substrate is located in the middle of the substrate, and the two LTE antennas are arranged at both ends of the substrate respectively. The two LTE antennas each include an antenna radiation network, an antenna resistor and an antenna feeding network, wherein the antenna feeding network is arranged on the back of the PCB substrate; a microstrip radiation isolation plate is arranged between the two antennas to increase isolation.

2. The high isolation multi-frequency antenna circuit board according to claim 1, characterized in that: The two LTE antennas are respectively a main antenna and a secondary antenna; wherein, the secondary antenna includes a low-frequency radiation branch, a medium-high frequency radiation branch, and a coupled radiation branch, and the coupled radiation branch is arranged in the middle position of the low-frequency and medium-high frequency radiation networks; the main antenna includes a low-frequency and medium-frequency radiation branch, a high-frequency radiation branch, and a coupled radiation branch, and the coupled radiation branch is arranged on the back of the PCB substrate.

3. The high isolation multi-frequency antenna circuit board according to claim 2, characterized in that: The main antenna coupling radiation branch is located directly below the low-frequency and medium-frequency radiation branches.

4. The high isolation multi-frequency antenna circuit board according to claim 2, characterized in that: The sizes of the LTE main antenna and the secondary antenna are both less than 40x30mm.

5. The high isolation multi-frequency antenna circuit board according to claim 1, characterized in that: The microstrip radiation isolation plate is arranged at one side of the main antenna and is located between the main antenna and the GNSS antenna.

6. The high isolation multi-frequency antenna circuit board according to claim 5, characterized in that: The microstrip radiation isolation sheet is arranged at a position close to the edge of the PCB substrate.

7. The high isolation multi-frequency antenna circuit board according to claim 1, characterized in that: The positions and resistance values ​​of the two antenna resistors are changed according to the isolation index between the two antennas.

8. The high isolation multi-frequency antenna circuit board according to claim 7, characterized in that: The antenna resistor is selected according to different application scenarios.

9. The high isolation multi-frequency antenna circuit board according to claim 1, characterized in that: The LTE antenna covers frequency bands including 698-960 MHz and 1710-2700 MHz.

10. High isolation multi-frequency antenna system, characterized by: A high-isolation multi-frequency antenna circuit board comprising any one of claims 1 to 9.

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