A compact structure high-isolation ultra-wideband transceiving antenna array

Abstract

The utility model discloses a kind of compact structure high-isolation ultra-wideband transceiving antenna array, including three antenna units, the three antenna units include one transmitting antenna unit and two receiving antenna units;Each the antenna unit includes dielectric substrate carrier, printed antenna patch, plug-in microstrip feed conductor and metal via;The utility model is set up multiple cut corners on rectangular printed antenna patch, to improve the adaptability of antenna to tight space. The unit in the original antenna array is placed at an angle of 45 degrees, and the receiving antenna is placed at half the wavelength corresponding to the channel9 center frequency with the unit geometric center as the reference. Not only can it achieve the demand of ultra-wideband angle positioning, but also effectively improve the isolation between units.

Description

Technical Field

[0001] This utility model relates to the field of ultra-wideband transceiver antenna arrays, specifically a compact, highly isolated ultra-wideband transceiver antenna array. Background Technology

[0002] Ultra-wideband (UWB) is suitable for a wide range of wireless systems. UWB radar signals are insensitive to channel fading, have low transmitted signal power spectral density, and consume significantly less power than existing traditional radio technologies. In particular, they exhibit low interference characteristics against other wireless systems and possess strong anti-interference capabilities and high-precision range resolution. UWB radar operates on a principle similar to Time of Flight (TOF). A signal is transmitted from the transmitter, bounces back to the receiver after hitting an obstacle, and the transmission distance is calculated by multiplying the time difference between transmission and reception by the speed of light. UWB radar utilizes the Doppler effect of wireless signals to detect changes in the surrounding electromagnetic environment. Moving objects emit electromagnetic waves, and by applying a frequency shift to these waves, the presence of movement can be determined by observing the characteristics of changes in the surrounding environment.

[0003] With the rapid development of radar sensing applications and the increasing demand for device portability, higher requirements are being placed on the antennas of mobile devices and wireless system transceiver terminals. In wireless communication systems, antenna isolation is a core indicator measuring the degree of electromagnetic energy coupling between different radiating elements. Higher antenna isolation results in less interference from co-channel signals, reducing interference from transmitted signals to received signals and improving the anti-interference capability and signal transmission quality of the communication system. For IR-UWB radar, the energy coupled by the antenna can cause saturation of the signal at close range, leading to the loss of some information at close range. Higher antenna isolation, at the same transmit power, results in less saturation of the signal at close range, and thus stronger radar performance.

[0004] Therefore, it is necessary to provide an ultra-wideband antenna array with a compact structure and high isolation transceiver units. Compared to traditional antenna arrays, this array structure has transmitting and receiving units with ranging and angle measurement functions. Not only does it achieve high isolation between the transmitting and receiving units within a compact structure, but each unit can also operate in the ultra-wideband Channel 9 frequency band. This antenna array structure has greater adaptability in radar precision sensing applications in IoT smart homes, connected vehicles, and the Industrial Internet, helping to better address diverse communication needs. Utility Model Content

[0005] To address the shortcomings of existing technologies, this invention provides a compact, highly isolated, ultra-wideband transceiver antenna array. This invention improves the antenna's adaptability to tight spaces by setting multiple chamfers on a rectangular printed antenna patch. The elements in the original antenna array are placed at a 45-degree angle, with the geometric center of each element as the reference, and the receiving antenna is positioned at half the wavelength corresponding to the center frequency of channel 9. This not only meets the requirements for ultra-wideband angle measurement and positioning but also effectively improves the isolation between elements.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A compact, high-isolation, ultra-wideband transceiver antenna array includes three antenna elements: one transmitting antenna element and two receiving antenna elements. Each antenna element includes a dielectric substrate carrier, a printed antenna patch, an insertable microstrip feed strip, and a metal via. The printed antenna patch and the insertable microstrip feed strip are disposed on the upper surface of the dielectric substrate carrier. The printed antenna patch has a rectangular groove, and the insertable microstrip feed strip is located within the rectangular groove and electrically connected to the printed antenna patch. The printed antenna patch has a first [feature] along its length direction. The first rectangular side and the second rectangular side along the width direction are both provided with a 45° chamfer; a first gap and a second gap are symmetrically provided between the insertable microstrip feed conductor and the printed antenna patch, the depth of the first gap and the second gap is less than or equal to half the length of the second rectangular side, and the width is less than or equal to the width of the insertable microstrip feed conductor; the dielectric substrate carrier is divided into an antenna layer and a ground metal layer from top to bottom, one end of the metal via is electrically connected to the insertable microstrip feed conductor, and the other end passes through the ground metal layer to connect with external signals;

[0008] The horizontal spacing between the two receiving antenna elements is half the wavelength corresponding to the center frequency of the ultra-wideband channel 9, and they are located on the right side of the antenna array; the transmitting antenna element is located on the left side of the antenna array, away from the two receiving antenna elements; all three antenna elements are rotated 45° counterclockwise with their geometric centers as a reference, and after rotation, the geometric centers of the three antenna elements are located on the same horizontal line.

[0009] More preferably, the rectangular groove is located at the middle position on the opposite side of the first rectangular side of the printed antenna patch.

[0010] Furthermore, the metal via is a metal via-to-microstrip feeding structure;

[0011] Further preferably, the edge of the dielectric substrate carrier is close to the chamfer position of different antenna elements.

[0012] More preferably, the dielectric constant of the dielectric substrate carrier is greater than or equal to 2, and the loss tangent is less than or equal to 10°. -3 The thickness is less than or equal to 3mm.

[0013] Further preferably, the lengths of the first rectangular side and the second rectangular side of the printed antenna patch are matched with the target center frequency of the antenna.

[0014] Further preferably, the transmitting antenna unit and the two receiving antenna units are both directional antennas, with small back lobes in the XOZ and YOZ planes normal to the antenna surface, and a half-beamwidth of ±60° or more.

[0015] This utility model has the following beneficial effects:

[0016] High isolation performance: By rotating the three antenna elements counterclockwise by 45° around their geometric center, the radiation direction characteristics of each element are altered, reducing electromagnetic energy coupling between elements. Simultaneously, the transmitting and receiving antenna elements are positioned on opposite sides, with the two receiving antenna elements arranged at a specific interval, further reducing signal interference. At the center frequency of 7.9872 GHz in ultra-wideband channel 9, the isolation between the transmitting and receiving elements reaches over 30 dB, and the isolation between the receiving elements is approximately 20 dB. This effectively avoids interference between the transmitted and received signals, improves the short-range detection accuracy of the radar system, and prevents information loss due to short-range signal saturation.

[0017] Compact structural design: The 45° chamfering of the printed antenna patch reduces the space occupied by the antenna element, allowing the edge of the dielectric substrate carrier to be close to the chamfer position, significantly reducing the overall size of the array. The width and height are only 7 cm and 1.7 cm respectively, meeting the process design requirements for miniaturization of mobile terminals and suitable for scenarios that are sensitive to device size, such as IoT smart homes and vehicle networking.

[0018] Ultra-wideband operation capability: The lengths of the first and second rectangular sides of the antenna element are matched with the target center frequency. Combined with the insertion microstrip feed and slot design, the array can be stably operated in the ultra-wideband channel 9 band. The return loss can reach -35dB at the center frequency, which meets the wideband communication requirements of ultra-wideband radar.

[0019] Precise angle measurement and positioning: The horizontal spacing between the two receiving antenna elements is set to half the wavelength corresponding to the center frequency of the ultra-wideband channel 9. Combined with the directional radiation characteristics of each element (half beamwidth ±60° or more), high-precision angle measurement can be achieved through the phase difference of the received signal, which meets the requirements of ultra-wideband angle measurement FOV (field of view) and improves the accuracy of the radar system in positioning, sensing and other applications.

[0020] Easy to integrate and manufacture: The printed circuit board process is simple in structure, and the position and connection relationship of each component (printed antenna patch, microstrip feed conductor, metal via, etc.) are clear, which facilitates mass production and easy integration with other circuits, reducing the overall design complexity and manufacturing cost of the equipment. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the overall structure of the high-isolation, compact, ultra-wideband radar sensing antenna array of this utility model.

[0022] Figure 2 The graph shows the return loss curves of each element in the high-isolation, compact structure ultra-wideband radar sensing antenna array of this utility model (vertical axis is return loss / dB, horizontal axis is frequency / GHz).

[0023] Figure 3 This is a graph showing the inter-element isolation of the high-isolation, compact structure ultra-wideband radar sensing antenna array of this invention (vertical axis is isolation / dB, horizontal axis is frequency / GHz).

[0024] Figure 4 This is a schematic diagram of the radiation direction of the receiving antenna of the first receiving unit of this utility model at the XOZ plane at the frequency of 7.9872GHz;

[0025] Figure 5 This is a schematic diagram of the radiation direction of the receiving antenna of the first receiving unit of this utility model in the YOZ plane at a frequency of 7.9872GHz;

[0026] Figure 6 This is a schematic diagram of the radiation direction of the receiving antenna of the second receiving unit of this utility model at the XOZ plane at the frequency of 7.9872GHz;

[0027] Figure 7 This is a schematic diagram of the radiation direction of the receiving antenna of the second receiving unit of this utility model in the YOZ plane at the frequency of 7.9872GHz;

[0028] Figure 8 This is a schematic diagram of the radiation direction of the transmitting antenna of the transmitting unit of this utility model at the XOZ plane at the frequency of 7.9872GHz;

[0029] Figure 9 This is a schematic diagram of the radiation direction of the transmitting antenna of the transmitting unit of this utility model in the YOZ plane at the frequency of 7.9872GHz.

[0030] Figure 10 This is a partial schematic diagram of the back of the antenna unit of this utility model.

[0031] Figure 11 This is a perspective view of the antenna unit of this utility model. Detailed Implementation

[0032] The present invention will be further described below with reference to the accompanying drawings and relevant knowledge. Obviously, the described applications are only some embodiments of the present invention, and not all embodiments.

[0033] The present invention will be further described in detail below with reference to the accompanying drawings.

[0034] The technical problem to be solved by this utility model is to provide a high-isolation, compact, ultra-wideband radar sensing antenna array. The antenna array has three elements: one transmitting antenna and two receiving antennas. Through optimization of the antenna element chamfering angle and structural design of the element arrangement, a compact antenna array can achieve high transmit / receive isolation and operate in the ultra-wideband Channel 9 frequency band, meeting the miniaturization process design requirements of today's mobile terminals.

[0035] Reference Figures 1-9 As shown, a compact structure, high isolation, ultra-wideband transceiver antenna array, and an ultra-wideband radar antenna element are disclosed. The antenna element includes a dielectric substrate carrier 1, a printed antenna patch 2, an insertable microstrip feed conductor 3, and a metal via 12.

[0036] The upper surface of the dielectric substrate carrier 1 is provided with a printed antenna patch 2 and an insertable microstrip feed conductor 3. The printed antenna patch 2 is provided with a rectangular groove 4, and the insertable microstrip feed conductor 3 is electrically connected to the rectangular printed antenna patch 2 in the rectangular groove 4.

[0037] The printed antenna patch 2 includes a first rectangular side 5 and a second rectangular side 6. The first rectangular side 5 is the length of the rectangular printed antenna patch, and the second rectangular side 6 is the width of the rectangular printed antenna patch. The length of the first rectangular side and the length of the second rectangular side are matched with the target center frequency of the antenna.

[0038] This invention applies a 45° chamfer to each pair of rectangular sides;

[0039] A first gap 7 and a second gap 8 are symmetrically arranged between the insertable microstrip feed conductor 3 and the rectangular printed antenna patch 2. The depth of the first gap 7 and the second gap 8 is less than or equal to half the side of the second rectangle, and the width of the first gap 7 and the second gap 8 is less than or equal to the width of the insertable microstrip feed conductor 3.

[0040] Reference Figures 10-11 As shown, the antenna element is divided into an antenna layer and a ground metal layer 13 from top to bottom. The insert-type microstrip feed conductor 3 is electrically connected to one end of the metal via 12, and the other end of the metal via 12 passes through the ground metal layer 13 to connect with external signals.

[0041] The antenna element is a center-inserted microstrip-fed antenna element, with a rectangular groove positioned at the midpoint of the opposite side of the first rectangular edge 5 of the rectangular printed antenna patch.

[0042] Reference Figure 1 As shown, this embodiment of the present invention provides an ultra-wideband radar antenna array, which includes three antenna elements; of the antenna elements included in the antenna array, one is a transmitting antenna element 9 and two are receiving antenna elements.

[0043] The horizontal spacing between the two receiving units of the antenna array is half the wavelength corresponding to the center frequency of the ultra-wideband channel 9. The two receiving antenna units are located on the right side of the array structure of this invention, namely the first receiving unit 10 and the second receiving unit 11. The transmitting unit of the antenna array is located away from the two receiving units, and the distance between them is preferably between half the wavelength and twice the wavelength corresponding to the center frequency of channel 9, located on the left side of the array structure of this invention.

[0044] Preferably, the antenna array elements are rotated 45° counterclockwise from their geometric centers. After rotation, the geometric centers of the three antenna elements are on a horizontal line.

[0045] Preferably, the metal via is a metal via-to-microstrip feed.

[0046] Preferably, the edge of the dielectric substrate carrier is close to the chamfer position of different antenna elements, which effectively reduces the volume occupied by the antenna array.

[0047] Preferably, the dielectric constant of the dielectric substrate carrier is greater than or equal to 2, and the tangent of its loss angle is less than or equal to 10°. -3 Its thickness is less than or equal to 3mm.

[0048] The ultra-wideband antenna array proposed in this invention has a simple and compact structure with significant isolation. The antenna array has a low profile and is composed of modified rectangular metal patches of different sizes. Its simple structure is easy to manufacture and integrate with circuitry. The compact multi-step polarization diversity ultra-wideband antenna of this invention has a width of 7 cm and a height of 1.7 cm, where the width refers to the long side of the rectangular frame and the height refers to the short side. It has a compact structure and higher isolation than conventionally arranged ultra-wideband antenna arrays. Performance testing shows that it can operate in the ultra-wideband Channel 9 communication band, achieving an isolation of 30 dB between the transmitting and receiving antenna elements within a compact space.

[0049] Reference Figure 1This utility model discloses a high-isolation, compact structure ultra-wideband radar sensing antenna array. The array includes a dielectric substrate carrier 1, a printed monopole antenna board (printed antenna patch 2), a metal ground plane, and a microstrip feed line conductor 3. The printed monopole antenna board is on the front side of the dielectric substrate carrier, and the metal ground plane is on the back side of the dielectric substrate carrier.

[0050] Reference Figures 2-3 , Figure 2 This is a return loss curve of each element in a high-isolation, compact, ultra-wideband radar sensing antenna array according to this invention. Figure 2 The vertical axis represents return loss in dB, and the horizontal axis represents frequency in GHz. Figure 2 It can be seen that the return loss curves of the high isolation compact structure ultra-wideband radar sensing antenna array units in this embodiment are very consistent, and they can operate in the ultra-wideband channel 9 communication band. Their resonant point corresponds to the center frequency of channel 9, 7.9872GHz, reaching -35dB.

[0051] Figure 3 An inter-element isolation curve of a high-isolation, compact structure ultra-wideband radar sensing antenna array provided as an embodiment of this utility model. Figure 3 The vertical axis represents isolation in dB, and the horizontal axis represents frequency in GHz. Figure 3 As can be seen, in this embodiment, the isolation between the two receiving units of the high-isolation compact ultra-wideband radar sensing antenna array, S21 and S12, is approximately 20 dB at the center frequency of channel 9 (7.9872 GHz), and is even higher in other ranges of channel 9. The isolation between the transmitting and receiving antenna units, S23 and S32, is approximately 30 dB at the center frequency of channel 9 (7.9872 GHz), and is even higher in other ranges of channel 9. The isolation between the transmitting and receiving antenna units, S13 and S31, is approximately 34 dB at the center frequency of channel 9 (7.9872 GHz), and is even higher in other ranges of channel 9.

[0052] In this invention, all antenna elements are directional antennas. For radar applications, the radiation pattern characteristics of the antenna surface normal are mainly examined. Figure 4 , Figure 5 These are schematic diagrams showing the radiation directions of the first receiving unit 10 of a high-isolation, compact ultra-wideband radar sensing antenna array at a frequency of 7.9872 GHz, according to one embodiment of this utility model. Figure 6 , Figure 7These are schematic diagrams showing the radiation directions of the second receiving unit 11 of a high-isolation, compact ultra-wideband radar sensing antenna array at a frequency of 7.9872 GHz, representing one embodiment of this utility model. Figure 8 , Figure 9 These are schematic diagrams illustrating the XOZ and YOZ radiation patterns of a high-isolation, compact, ultra-wideband radar sensing antenna array transmitting unit antenna at a frequency of 7.9872 GHz, according to one embodiment of this invention. As can be seen from the radiation patterns of the transmitting antenna unit and the two receiving antenna units at 7.9872 GHz, each antenna unit maintains good directional characteristics and a small back lobe in the XOZ and YOZ planes normal to the antenna surface. Furthermore, the half-beamwidth can reach ±60° or more, meeting the requirements of ultra-wideband angular field of view (FOV).

[0053] Dielectric substrate carrier 1: Serves as the supporting foundation for the antenna element, and is selected with a dielectric constant ≥ 2 and a loss tangent ≤ 10°. -3 Materials with a thickness ≤ 3mm (such as FR4 substrate). Low loss characteristics reduce energy loss during signal transmission, ensuring efficient antenna operation; the thinner thickness reduces the array's profile height, enhancing structural compactness.

[0054] Printed antenna patch 2: Employs a rectangular design, with the first rectangular side along its length and the second rectangular side along its width. Its length is matched to the wavelength corresponding to the center frequency (7.9872 GHz) of the ultra-wideband channel 9 to achieve resonance at a specific frequency. The 45° chamfer design on the patch alters the current distribution path, reduces the patch's equivalent size, allows the antenna element to better fit within a compact space, and optimizes the antenna's impedance matching characteristics.

[0055] Rectangular groove 4 and insert-type microstrip feed conductor 3: The rectangular groove is located in the middle position on the opposite side of the first rectangular side 5. The insert-type microstrip feed conductor 3 is inserted into the groove and electrically connected to the patch. This feeding method can effectively excite the antenna to generate wideband resonance, ensure good matching of the antenna in the ultra-wideband range, and simplify the feeding structure, making it easy to connect to external circuits.

[0056] The first slot 7 and the second slot 8 are symmetrically positioned between the insertable microstrip feed conductor 3 and the printed antenna patch 2. The slot depth is ≤ half the length of the second rectangular side 6, and the width is ≤ the width of the feed conductor. The presence of the slots adjusts the impedance characteristics of the antenna, widens the bandwidth, and enables the antenna to maintain stable return loss performance in the ultra-wideband channel 9 band, ensuring efficient signal transmission.

[0057] Metal via: A metal via-to-microstrip feeding method is adopted, with one end electrically connected to the inserted microstrip feed conductor, and the other end passing through the ground plane metal layer to connect to the external signal. This structure realizes vertical feeding between the antenna layer and the external circuit, reduces the impact of the feed network on the antenna radiation characteristics, and ensures the stability of signal transmission.

[0058] Ground metal layer: Located below the dielectric substrate carrier, it serves as the ground reference surface of the antenna. It can reflect the energy radiated backward by the antenna, enhance the forward radiation intensity, reduce back lobe interference, and improve the directional radiation performance of the antenna.

[0059] The antenna array layout and the effects of its various technical features, the number and arrangement of elements: The array contains one transmitting antenna element and two receiving antenna elements. The transmitting element is located on the left and the two receiving elements are located on the right. This separate layout reduces the direct interference of the transmitted signal to the received signal and is the basis for improving isolation.

[0060] Unit rotation design: Each of the three antenna elements is rotated 45° counterclockwise from its geometric center, resulting in collinear geometric centers. This design alters the radiation pattern of each element, lengthening the electromagnetic coupling path between elements, reducing coupling energy, and significantly improving isolation. Simultaneously, the rotated layout facilitates arrangement within a compact space, further reducing the array size.

[0061] Receiver unit spacing: The horizontal spacing between the two receiver units is set to half the wavelength (approximately 18.75 mm) corresponding to the center frequency of ultra-wideband channel 9. This spacing ensures that the phase difference generated when the two receiver units receive the same signal is within a reasonable range. High-precision angle measurement can be achieved through phase difference calculation, meeting the angle measurement and positioning requirements of ultra-wideband radar.

[0062] Directional radiation characteristics: Each antenna element is a directional antenna. In the XOZ and YOZ radiation patterns at 7.9872 GHz, the back lobes are small, and the half-beamwidth is ≥ ±60°. This characteristic ensures that the radar system can effectively detect targets in a specific direction, while reducing the interference of side lobes to signals in other directions, thus improving the accuracy of detection and anti-interference capability.

[0063] Overall performance verification shows that, through the above structural design, this compact, high-isolation ultra-wideband transceiver antenna array exhibits the following performance in actual testing: It operates in the ultra-wideband channel 9, with a return loss of -35dB at the center frequency of 7.9872GHz, meeting communication stability requirements; the isolation between the transmitting and receiving units is ≥30dB, and the isolation between receiving units is ≥20dB, effectively avoiding signal interference; the array is compact (7cm wide, 1.7cm high), suitable for miniaturized devices; the angular measurement field of view is ≥±60°, providing high positioning accuracy, and it can be widely applied in radar sensing scenarios in fields such as IoT smart homes, vehicle networks, and the industrial internet.

[0064] Although some embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, and all such changes and alterations should fall within the scope of the present invention.

Claims

1. A compact, high-isolation, ultra-wideband transceiver antenna array, characterized in that, The system includes three antenna elements: one transmitting antenna element and two receiving antenna elements. Each antenna element comprises a dielectric substrate carrier, a printed antenna patch, an insertable microstrip feed strip, and metal vias. The printed antenna patch and the insertable microstrip feed strip are disposed on the upper surface of the dielectric substrate carrier. The printed antenna patch has a rectangular groove, and the insertable microstrip feed strip is located within the rectangular groove and electrically connected to the printed antenna patch. The printed antenna patch has a first rectangular side along its length and a second rectangular side along its width. Both the first and second rectangular sides are provided with a 45° chamfer; the insert-type microstrip feed conductor and the printed antenna patch are symmetrically provided with a first gap and a second gap; the horizontal spacing between the two receiving antenna elements is half the wavelength corresponding to the center frequency of the ultra-wideband channel 9, and they are located on the right side of the antenna array; the transmitting antenna element is located on the left side of the antenna array, away from the two receiving antenna elements; all three antenna elements are rotated 45° counterclockwise with their geometric centers as a reference, and after rotation, the geometric centers of the three antenna elements are located on the same horizontal line.

2. The antenna array according to claim 1, characterized in that, The rectangular groove is located at the middle position on the opposite side of the first rectangular side of the printed antenna patch.

3. The antenna array according to claim 1, characterized in that, The metal via is a metal via-to-microstrip feeding structure.

4. The antenna array according to claim 1, characterized in that, The depth of the first gap and the second gap is less than or equal to half the length of the side of the second rectangle, and the width is less than or equal to the width of the insert-type microstrip feed conductor. The dielectric substrate carrier is divided into an antenna layer and a ground metal layer from top to bottom. One end of the metal via is electrically connected to the insert-type microstrip feed conductor, and the other end passes through the ground metal layer to connect with external signals.

5. The antenna array according to claim 1, characterized in that, The dielectric substrate carrier has a dielectric constant greater than or equal to 2 and a thickness less than or equal to 3 mm.

6. The antenna array according to claim 1, characterized in that, The lengths of the first and second rectangular sides of the printed antenna patch are matched with the target center frequency of the antenna.

7. The antenna array according to claim 1, characterized in that, The transmitting antenna unit and the two receiving antenna units are both directional antennas, with small back lobes in the XOZ and YOZ planes normal to the antenna surface, and a half-beamwidth of ±60° or more.

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