Circularly polarized antenna structure, wireless communication module and millimeter wave isolation communication module

Abstract

The invention provides a circularly polarized antenna structure, a wireless communication module and a millimeter wave isolation communication module. The antenna structure comprises a radiation layer, a grounding layer and a microstrip line feed layer which are sequentially stacked from top to bottom, the radiation layer comprises a central circular patch and a parasitic unit; two linear grooves which do not pass through the circle center are formed in the central circular patch along the diameter of the central circular patch; the parasitic unit is an arc-shaped patch and is arranged on the periphery of the central circular patch, and the circle center of the arc-shaped patch coincides with the circle center of the central circular patch; the extension of the linear groove does not touch the arc-shaped patch; and a feed copper column of the microstrip line feed layer penetrates through each layer and then is connected to the vicinity of the circle center of the radiation layer. The problem of polarization loss can be solved, the bandwidth of circular polarization is increased, and the wireless communication transmission quality is remarkably improved.

Description

Technical Field

[0001] The present invention relates to the field of antenna technology, and in particular to a circularly polarized antenna structure, a wireless communication module and a millimeter wave isolation communication module. Background Art

[0002] Existing terminal products use FPC cables to connect the circuits between PCBs inside the product. FPC connectors require physical contact and may be damaged or worn; in addition, the manufacturing and installation costs of FPC connectors are high.

[0003] In addition, the existing millimeter wave connector adopts linear polarization. When the polarization directions of the transmitting and receiving antennas are inconsistent, the reception effect of the linear polarization signal will be significantly reduced. This phenomenon is called polarization loss. In addition, the effective bandwidth of the traditional circularly polarized antenna is narrow, and the communication rate and capacity are low.

[0004] Therefore, how to improve the wear and tear caused by cable connections and the installation cost problems; how to solve the polarization loss caused by the change in the relative position of the transmitting and receiving antennas; and how to solve the problem of insufficient bandwidth of general circularly polarized antennas need to be solved urgently. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a circularly polarized antenna structure, a wireless communication module and a millimeter wave isolation communication module, which can overcome the polarization loss problem, increase the bandwidth of circular polarization, and significantly improve the quality of wireless communication transmission.

[0006] In order to solve the above technical problems, the first technical solution adopted by the present invention is:

[0007] A circularly polarized antenna structure comprises a radiation layer, a ground layer and a microstrip line feeding layer stacked in sequence from top to bottom, and adjacent layers are separated by a dielectric substrate;

[0008] The radiation layer includes a central circular patch and a parasitic unit; the central circular patch has two linear slots along its diameter that do not pass through the center of the circle; the parasitic unit is an arc-shaped patch, which is arranged on the periphery of the central circular patch, and the center of the arc-shaped patch coincides with the center of the central circular patch; the extension of the linear slot does not touch the arc-shaped patch;

[0009] The feeding copper column of the microstrip line feeding layer passes through each level and is connected to the vicinity of the center of the radiation layer.

[0010] Optionally, the number of the parasitic units is more than two; and the more than two parasitic units are evenly distributed around the periphery of the central circular patch.

[0011] Optionally, the number of the parasitic units is four; and the extension of the linear slot corresponds to the gap between two parasitic units.

[0012] Optionally, the diameter of the central circular patch is in the range of 1-1.5 mm; the width of the linear slot is in the range of 0.2-0.6 mm, and the length is in the range of 0.8-1.3 mm; the feeding copper column is connected to a position 0.4-0.5 mm away from the center of the circle.

[0013] Optionally, the size of the linear groove is width*length=0.4mm*1mm.

[0014] Optionally, the inner diameter of the arc-shaped patch is in the range of 0.6-0.7 mm, and the outer diameter is in the range of 0.9-1.1 mm.

[0015] Optionally, the gap between adjacent parasitic units ranges from 0.07 to 0.2 mm.

[0016] The second technical solution adopted by the present invention is:

[0017] A wireless communication module comprises the above-mentioned circularly polarized antenna structure, a packaging substrate and an RF IC; the circularly polarized antenna structure is arranged on the upper side of the packaging substrate, the RF IC is arranged on the lower side of the packaging substrate, and the feeding copper column on the circularly polarized antenna structure is connected to the RF IC.

[0018] Optionally, the central circular patch is a millimeter wave antenna patch.

[0019] The third technical solution adopted by the present invention is:

[0020] A millimeter wave isolation communication module, comprising a first millimeter wave communication unit and a second millimeter wave communication unit; the first millimeter wave communication unit comprises the above-mentioned wireless communication module; the second millimeter wave communication unit comprises the above-mentioned wireless communication module;

[0021] The radiation layer in the first millimeter wave communication unit and the radiation layer in the second millimeter wave communication unit are arranged correspondingly with a certain distance between them.

[0022] The beneficial effects of the present invention are as follows: the central circular patch of the radiation layer of the circular polarization antenna structure of the present invention has two straight grooves that do not pass through the center of the circle along its diameter, which can increase the circular polarization; at the same time, a parasitic unit is provided on the periphery of the central circular patch, and the extension of the straight groove does not touch the arc patch, which can further increase the bandwidth of the circular polarization; therefore, compared with the traditional circular polarization antenna structure, it has a higher available bandwidth, which can significantly improve the communication quality, enhance the signal coverage, reduce interference, and be applicable to more scenarios. The wireless communication module and millimeter wave isolation communication module based on the above-mentioned circular polarization antenna structure can replace the traditional physical contact with wireless communication, reduce the installation cost and increase the service life; more importantly, it can also solve the polarization loss problem caused by the change in the relative position of the transmitting and receiving antennas, so that the circularly polarized signals can be effectively received without being affected by the relative position change factor, thereby optimizing the wireless communication transmission quality again. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 A schematic diagram of the hierarchical structure of a circularly polarized antenna structure provided in an embodiment of the present invention;

[0024] Figure 2 A schematic diagram of the planar structure of a radiation layer in a circularly polarized antenna structure provided in an embodiment of the present invention;

[0025] Figure 3 A cross-sectional schematic diagram of a circularly polarized antenna structure provided by an embodiment of the present invention;

[0026] Figure 4 A schematic diagram of current distribution when the phase of the feed source of the central circular patch in the circularly polarized antenna structure provided by an embodiment of the present invention is 0 degrees;

[0027] Figure 5 A schematic diagram of current distribution when the phase of the feed source of the central circular patch in the circularly polarized antenna structure provided by an embodiment of the present invention is 180 degrees;

[0028] Figure 6 A schematic diagram of current distribution when the feed source phase of the radiation layer in the circularly polarized antenna structure provided by an embodiment of the present invention is 0 degrees;

[0029] Figure 7 A schematic diagram of current distribution when the feed source phase of the radiation layer in the circularly polarized antenna structure provided by an embodiment of the present invention is 180 degrees;

[0030] Figure 8 The bandwidth curve before and after the parasitic unit is added to the radiation layer in the circularly polarized antenna structure provided by the embodiment of the present invention;

[0031] Fig. 9 A schematic diagram of the structure of a wireless communication module provided in an embodiment of the present invention;

[0032] Fig.10 A schematic diagram of the structure of a millimeter wave isolation communication module provided in an embodiment of the present invention.

[0033] Description of labels:

[0034] 1. Circularly polarized antenna structure; 2. Package substrate; 3. RF IC;

[0035] 10. Radiating layer; 20. Grounding layer; 30. Microstrip line feeding layer; 40. Dielectric substrate;

[0036] 11. Central circular patch; 12. Linear slot; 13. Parasitic unit;

[0037] 31. Feed copper column;

[0038] A. A first millimeter wave communication unit; B. A second millimeter wave communication unit. DETAILED DESCRIPTION

[0039] In order to explain the technical content, achieved objectives and effects of the present invention in detail, the following is an explanation in conjunction with the implementation modes and the accompanying drawings.

[0040] The most critical concept of the present invention is that: the central circular patch of the radiation layer has two straight grooves along its diameter that do not pass through the center of the circle; the parasitic unit is an arc-shaped patch, which is arranged on the periphery of the central circular patch, and its center coincides with the center of the central circular patch; the extension of the straight groove does not touch the arc-shaped patch.

[0041] Embodiment 1

[0042] Please refer to Figures 1 to 8 This embodiment provides a circular polarization antenna structure, such as Figure 1 As shown, it includes a radiation layer 10, a ground layer 20 and a microstrip line feeding layer 30 stacked in sequence from top to bottom, and adjacent layers are separated by a dielectric substrate 40.

[0043] Among them, Figure 2 As shown, the radiation layer 10 includes a central circular patch 11 and a parasitic unit 13; the central circular patch 11 has two straight grooves 12 along its diameter that do not pass through the center of the circle; the parasitic unit 13 is an arc-shaped patch, the parasitic unit 13 is arranged on the periphery of the central circular patch 11, and is spaced a preset distance from the central element patch 11, and at the same time, the center of the arc-shaped patch coincides with the center of the central circular patch 11; in addition, the extension of the straight groove 12 does not touch the arc-shaped patch.

[0044] Among them, Figure 1 and Figure 3As shown, the microstrip line feeding layer 30 includes a feeding copper column 31, and the feeding copper column 31 passes through each layer and is connected to the vicinity of the center of the radiation layer 10. Here, the feeding copper column is connected to the vicinity of the center of the circle instead of the center of the circle because the impedance at the center of the circle is small and the impedance at the outer circle is large, so a matching point is found from the center of the circle to the radius of the circle to obtain the best matching impedance (such as matching 50ohm impedance) of the circularly polarized antenna structure of this embodiment.

[0045] The above circularly polarized antenna structure is a multi-layer plate structure as a whole, and the top radiation layer includes a central circular patch and a parasitic unit; the central circular patch serves as the main radiation antenna, and has two straight line slots along its diameter that do not pass through the center of the circle, which can enable the main radiation antenna to generate orthogonal surface currents to form circular polarization, thereby increasing the circular polarization of the main radiation antenna; at the same time, the parasitic unit arranged on the periphery of the main radiation antenna can also generate orthogonal surface currents, further increasing the circular polarization bandwidth of the radiation layer antenna and the effective width of the return loss. Therefore, compared with the existing circularly polarized antenna structure, the circularly polarized antenna structure of this embodiment has a significantly enhanced circular polarization bandwidth, so the antenna has a higher available bandwidth and can better and more effectively receive circularly polarized signals.

[0046] In some specific embodiments, Figure 3 As shown, the feeding copper column is located at a position 0.4-0.5 mm away from the center of the central circular patch in the X-axis direction with the center of the circle as the origin, so as to match the optimal impedance of 50 ohms.

[0047] In some specific embodiments, the number of the parasitic units is more than two; more than two parasitic units are evenly distributed around the periphery of the central circular patch. Here, the corresponding circular polarization needs to be formed by the current direction in two directions, so the parasitic units are respectively configured in these two directions to generate resonance points, thereby increasing the bandwidth. There are two parasitic elements in one direction.

[0048] Preferably, if Figure 2 As shown, the number of the parasitic units 13 is four; the four arc-shaped patches are evenly distributed on the periphery of the central circular patch 11, so that the radiation layer 10 forms a central symmetrical structure. In addition, the extension of the linear slot 12 corresponds to the gap between the two parasitic units 13. It can be understood that the gap between the two corresponding parasitic units 13 and the linear slot 12 are located on the same straight line passing through the center of the central circular patch 11. Here, corresponding to the two directions of circular polarization, two parasitic units are set in one direction, and there are four parasitic units in total in the two directions, and the gap between the parasitic units is on the same straight line as the linear slot, so that the radiation layer forms a central symmetrical structure, obtains the best resonance effect, and the bandwidth of the radiation layer is maximized.

[0049] In some specific embodiments, the diameter of the central circular patch is in the range of 1-1.5 mm; the width of the linear slot is in the range of 0.2-0.6 mm, and the length is in the range of 0.8-1.3 mm; the feeding copper column is connected to a position 0.4-0.5 mm away from the center of the circle. Here, the linear slot size is limited to the above value range, which can ensure that the linear slot produces circular polarization matching on the central circular patch, avoiding polarization mismatch due to excessive slot size, which becomes linear polarization.

[0050] Preferably, the size of the linear slot is width*length=0.4mm*1mm. Here, the optimal slot size can enable the central circular patch to produce the best circular polarization effect.

[0051] In some specific embodiments, the inner diameter of the arc patch is in the range of 0.6-0.7 mm, and the outer diameter is in the range of 0.9-1.1 mm. Here, by controlling the size of the arc patch, it is possible to ensure that the parasitic unit produces a good resonance effect to obtain the effect of increasing the bandwidth; it is possible to effectively avoid the mismatch problem caused by the impedance being too large or too small at high frequencies due to the parasitic unit being too large or too small.

[0052] In some specific implementations, the gap between adjacent parasitic units ranges from 0.07 to 0.2 mm to obtain a better matching degree.

[0053] Preferably, the gap between adjacent parasitic units is 0.1 mm.

[0054] The circularly polarized antenna structure provided in this embodiment has a central circular patch in the radiation layer. After a straight slot is provided, the current distribution of the central circular patch when the feed source phase is 0 degrees is as follows: Figure 4 As shown, it can be seen that the current direction is +yx; the current distribution of the central circular patch when the input source phase is 180 degrees is as follows Figure 5 As shown, the current direction is +y+x. It can be understood that after the central circular patch is slotted, the current direction of the main radiating antenna can be changed as the phase of the feed source changes, which can bring two orthogonal surface currents, so that the antenna generates circularly polarized radiation.

[0055] If, on the basis of the above, the outer periphery of the central circular patch of the radiation layer is increased as follows Figure 2 The four evenly distributed arc patches shown in FIG. 1 are used as parasitic units. The current distribution of the radiation layer when the feed source phase is 0 degrees is as follows: Figure 6 As shown, the current distribution of the radiation layer when the feeding source phase is 180 degrees is as follows Figure 7 As shown; the bandwidth curves before and after the parasitic unit is added to the radiation layer are as follows Figure 8As shown, it can be understood that the addition of four parasitic elements will add high-frequency modes to the radiating layer, thereby further increasing the bandwidth of the circular polarization of the radiating layer antenna. Figure 8 It can be seen that the circular polarization bandwidth presented by the black dotted curve is about 59.3-60.2 GHz, and the circular polarization bandwidth presented by the black solid line curve is about 59.3-66 GHz. It can be seen that after adding the parasitic unit, the bandwidth of the radiation layer antenna is increased by about 5.8 GHz.

[0056] Embodiment 2

[0057] Please refer to Fig. 9 This embodiment is further expanded on the basis of the first embodiment and provides a wireless communication module.

[0058] The wireless communication module provided in this embodiment is as follows: Fig. 9 As shown, it includes the circularly polarized antenna structure 1 described in the above embodiment, and also includes a packaging substrate 2 and an RF IC3; the circularly polarized antenna structure 1 is arranged on the upper surface of the packaging substrate 2, the RF IC3 is arranged on the lower surface of the packaging substrate 2, and the feeding copper column on the circularly polarized antenna structure is connected to the RF IC.

[0059] It can be understood that the wireless communication module provided in this embodiment, firstly, can replace the FPC connector for the circuit connection between the PCB and the PCB inside the product, and solve the wear and cost problems caused by the physical connection in a wireless way; secondly, its antenna structure adopts the circularly polarized antenna structure described in Example 1. Compared with the wireless communication module using the traditional microstrip circularly polarized antenna, the circular polarization bandwidth of the antenna will be significantly enhanced, and the available bandwidth of the antenna will be improved; in particular, when the relative position between the antenna in the wireless communication module as the transmitting end and the antenna in the wireless communication module as the receiving end changes, the circularly polarized signal can still be effectively received. Therefore, the wireless communication module of this embodiment has a higher available bandwidth, which can significantly improve the communication quality, enhance the signal coverage, reduce interference, and be applicable to more scenarios.

[0060] In some specific embodiments, if the central circular patch is a millimeter wave antenna patch, the wireless communication module is a millimeter wave communication module, which performs wireless communication transmission based on millimeter wave technology and has the advantages of higher data transmission rate, wider bandwidth, lower latency, and stronger anti-interference.

[0061] In some specific implementations, the wireless communication module of this embodiment can print the circularly polarized antenna structure described in Example 1 with the radiation layer facing upward on one side of the packaging substrate, set the RF IC on the other side of the packaging substrate by flip-chip means, and then feed the circularly polarized antenna structure to the TX / RX of the RF IC through the perforation, and finally package it using IC. It can be seen that the wireless communication module of this embodiment also has the advantages of simple structure and simple packaging. In particular, when the central circular patch is implemented using a millimeter wave antenna patch, since the millimeter wave circularly polarized antenna is relatively small in size, it can be better packaged in the substrate and connected to the RF IC by flip-chip technology. Compared with the traditional FPC physical connection method, it can greatly reduce the volume of the wireless communication module and achieve miniaturization.

[0062] Embodiment 3

[0063] See also Fig.10 This embodiment is further expanded based on the above-mentioned embodiment 2 and provides a millimeter wave isolation communication module.

[0064] The millimeter wave isolation communication module provided in this embodiment is as follows: Fig.10 As shown, it includes a first millimeter wave communication unit A and a second millimeter wave communication unit B. The first millimeter wave communication unit A includes the millimeter wave communication module described in Example 2; the second millimeter wave communication unit B includes the millimeter wave communication module described in Example 2; the millimeter wave communication module includes the circularly polarized antenna structure 1, the packaging substrate 2 and the RF IC 3 described in Example 2.

[0065] At the same time, in the millimeter wave isolation communication module, the antennas of the first millimeter wave communication unit A and the second millimeter wave communication unit B are arranged in a broadside manner, that is, the radiation layer of the circular polarization antenna structure 1 in the first millimeter wave communication unit A and the radiation layer of the circular polarization antenna structure 1 in the second millimeter wave communication unit are arranged in a corresponding manner with a certain distance between them. Fig.10 As shown, assuming that the first millimeter wave communication unit A is used as the transmitting end TX and the second millimeter wave communication unit B is used as the receiving end TX, isolated communication transmission between the transmitting end and the receiving end can be achieved.

[0066] In some specific embodiments, the millimeter wave isolation communication module can be a communication module with a simplex communication function, or a communication module with a duplex communication function. If the millimeter wave isolation communication module is a simplex communication module, one of the first millimeter wave communication unit and the second millimeter wave communication unit serves as a fixed receiving end, and the other serves as a fixed transmitting end. If the millimeter wave isolation communication module is a duplex communication module, both the first millimeter wave communication unit and the second millimeter wave communication unit can serve as a receiving end and a transmitting end, that is, both have transceiver functions at the same time.

[0067] It can be understood that the millimeter wave isolation communication module of this embodiment, whose millimeter wave antenna structure adopts the circularly polarized antenna structure described in the above-mentioned embodiment 1, will significantly enhance the circular polarization bandwidth of the antenna and improve the available bandwidth of the antenna compared to the millimeter wave isolation communication module using the traditional microstrip circularly polarized antenna; in particular, when the relative position between the antenna structure in the first millimeter wave communication unit and the antenna structure in the second millimeter wave communication unit changes, the circularly polarized signal can still be effectively received, thereby solving the polarization loss problem caused by the relative position change between the transmitting and receiving ends. Therefore, the millimeter wave isolation communication module of this embodiment has a higher available bandwidth, which can significantly improve the communication quality, enhance the signal coverage, reduce interference, and be applicable to more scenarios, and can better achieve dual-end safe isolation and high-speed transmission.

[0068] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent transformations made using the contents of the present invention's specification and drawings, or directly or indirectly applied in related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A circularly polarized antenna structure, characterized in that: It includes a radiation layer, a ground layer and a microstrip line feeding layer stacked in sequence from top to bottom, and adjacent layers are separated by a dielectric substrate; The radiation layer includes a central circular patch and a parasitic unit; the central circular patch has two linear slots along its diameter that do not pass through the center of the circle; the parasitic unit is an arc-shaped patch, which is arranged on the periphery of the central circular patch, and the center of the arc-shaped patch coincides with the center of the central circular patch; the extension of the linear slot does not touch the arc-shaped patch; The feeding copper column of the microstrip line feeding layer passes through each level and is connected to the vicinity of the center of the radiation layer.

2. The circularly polarized antenna structure according to claim 1, characterized in that: The number of the parasitic units is more than two; the more than two parasitic units are evenly distributed around the periphery of the central circular patch.

3. The circularly polarized antenna structure according to claim 2, characterized in that: The number of the parasitic units is four; the extension of the linear slot corresponds to the gap between two parasitic units.

4. The circularly polarized antenna structure according to claim 1, characterized in that: The diameter of the central circular patch is in the range of 1-1.5 mm; the width of the linear slot is in the range of 0.2-0.6 mm, and the length is in the range of 0.8-1.3 mm; the feeding copper column is connected to a position 0.4-0.5 mm away from the center of the circle.

5. The circularly polarized antenna structure according to claim 4, characterized in that: The size of the linear groove is width*length=0.4mm*1mm.

6. The circularly polarized antenna structure according to claim 1, characterized in that: The inner diameter of the arc-shaped patch is in the range of 0.6-0.7 mm, and the outer diameter is in the range of 0.9-1.1 mm.

7. The circularly polarized antenna structure according to claim 2, characterized in that: The gap between adjacent parasitic units ranges from 0.07 to 0.2 mm.

8. A wireless communication module, characterized in that: It comprises the circularly polarized antenna structure as described in any one of claims 1 to 7, as well as a packaging substrate and an RF IC; the circularly polarized antenna structure is arranged on the top of the packaging substrate, the RF IC is arranged under the packaging substrate, and the feeding copper column on the circularly polarized antenna structure is connected to the RF IC.

9. The wireless communication module according to claim 8, characterized in that: The central circular patch is a millimeter wave antenna patch.

10. A millimeter wave isolation communication module, characterized in that: It comprises a first millimeter wave communication unit and a second millimeter wave communication unit; the first millimeter wave communication unit comprises the wireless communication module according to claim 9; the second millimeter wave communication unit comprises the wireless communication module according to claim 9; The radiation layer in the first millimeter wave communication unit and the radiation layer in the second millimeter wave communication unit are arranged correspondingly with a certain distance between them.

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