CN113540826B - Linear tapered slit form-based radiating fin antenna array structure - Google Patents

Abstract

The invention discloses a radiating fin antenna array structure based on a linear tapered slot form, aiming at solving the problems that the existing design scheme cannot achieve effective heat dissipation and is not easy to form an antenna array during high frequency operation. The main points of the technical solution are: including a linear opening fin type metal heat sink, a metal base of the heat sink and a base plate, the upper surface of the base plate is connected with the metal base of the heat sink, and the lower surface of the base plate is connected with the heat source chip, and it is characterized in that the heat dissipation A double-ridged waveguide cavity array serving as an antenna radiation aperture is opened on the sheet metal base, and a linear opening fin type metal heat sink is arranged on the double-ridged waveguide cavity array. The invention realizes the conformality of the antenna and the heat dissipation structure, and greatly saves the system space.

Description

A Radiator Antenna Array Structure Based on Linear Tapered Slots

technical field

The present invention relates to the technical field of antennas, in particular to a heat sink antenna array structure based on the form of linear tapered slits.

Background technique

In recent years, in order to make full use of the limited system space resources, reduce the energy loss caused by excessively long feeders and interface discontinuities, and realize miniaturized and highly integrated wireless communication systems, the design often includes chips, Various active and passive components including front-end circuits and RF antennas are integrated in the same package. Although the total input power of the wireless communication system is gradually decreasing, due to the further reduction of the overall size of the system, the power consumption per unit volume is actually increasing. work, or even severely damaged. Therefore, in the actual design, it is often necessary to consider the heat dissipation performance of the system at the same time. In order to dissipate excess heat in the system, and considering the thermal conductivity of materials, additional metal heat dissipation structures, such as common metal heat sinks, are usually designed. However, in practical applications, the metal heat sink structure is prone to parasitic electromagnetic coupling with various radio frequency devices such as adjacent integrated circuits and antennas, thereby causing electromagnetic compatibility problems, and its own parasitic radiation may also lead to distortion of the overall pattern of the antenna. and deterioration, affecting the normal work of the system. In this regard, the previous solutions often hope to suppress the radiation generated by the metal heat sink, but this will increase the design complexity. The heat dissipation antenna scheme of electrothermal coordination provides a new idea, which can take into account the normal operation and heat dissipation performance of the wireless communication system on the basis of conformal design.

The existing heat dissipation antenna scheme mainly adopts the combination of a heat sink and a microstrip patch antenna. The most direct way is to add a fin-type metal heat sink on top of the microstrip patch antenna. However, this solution also requires the size of the metal heat sink base to be exactly the same as the size of the microstrip patch. When the operating frequency increases, the size of the microstrip patch decreases with the shortening of the wavelength, which greatly limits the size of the metal heat sink. Design space, resulting in insufficient heat dissipation capacity. In addition, this solution is not easy to perform antenna arrays, and it is difficult to meet some application scenarios that require high gain, narrow beam, and beam scanning. The above problems are particularly serious for the expansion of heat dissipation antennas in the millimeter wave frequency band.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a heat sink antenna array structure based on the form of linear tapered slits, by designing the traditional fin-type metal heat sink into a linear tapered structure, and introducing a double-ridged waveguide cavity into the base as the radiation aperture , the heat sink structure is designed as an antenna array with radiation function, and the conformal structure of the antenna and the heat sink is realized, which is suitable for the integrated design of the antenna and the heat dissipation structure, and improves the integration degree of the system.

The above-mentioned technical purpose of the present invention is achieved through the following technical solutions:

A heat sink antenna array structure based on the form of linear tapered slits, comprising a linear opening fin type metal heat sink, a heat sink metal base and a base plate, the upper surface of the base plate is connected with the heat sink metal base, and the lower surface of the base plate is connected with a heat source chip connected, the metal base of the heat sink is provided with a double-ridged waveguide cavity array serving as an antenna radiation aperture, and the double-ridged waveguide cavity array is provided with a linear opening fin type metal heat sink;

The substrate includes multiple metal layers, a dielectric layer is arranged between the metal layers, and the dielectric layer contains an array of metal vias for forming a substrate-integrated waveguide structure.

The present invention is further provided as follows: the opening size of the double-ridged waveguide cavity array meets the TE10 working mode of the double-ridged waveguide, and each double-ridged waveguide cavity and two adjacent linear opening fin-type metal heat sinks form a linear cone Cut the slot antenna.

The present invention is further provided as follows: the height of the linear opening fin type metal heat sink should be greater than half the working wavelength, the opening size of the linear taper slit should be less than half the working wavelength, and the space between the fins of the heat sink should be less than one half of the working wavelength. The spacing should be no greater than one operating wavelength.

The present invention is further provided as follows: the substrate is located below the metal base of the heat sink, and includes an upper metal layer, an upper dielectric layer, a middle metal layer, a middle dielectric layer, a lower metal layer, a lower dielectric layer, and the underlying metal layer, where,

The upper metal layer, the upper dielectric layer, the upper metal via array, the middle metal layer, the middle dielectric layer, the middle metal via array, the lower metal layer, the lower dielectric layer, the lower metal via array, and the bottom metal layer constitute the vertical base. Chip integrated waveguide structure.

The present invention is further arranged as follows: the middle layer metal layer, the stripline feeding input structure and the lower layer metal layer constitute the stripline T-type input power distribution and feeding network.

The present invention is further arranged as follows: the upper metal layer has an upper rectangular opening array, the middle metal layer has a middle rectangular opening array, and the lower metal layer has a bottom rectangular opening array, which corresponds to the double-ridged waveguide cavity array on the metal base of the heat sink. , as the feed structure of the heat sink antenna array.

A further arrangement of the present invention is that: a stripline feeding input structure for switching and feeding with the vertical substrate integrated waveguide structure is arranged on the middle dielectric layer.

According to a further arrangement of the present invention, the substrate is a low temperature co-fired ceramic substrate.

The present invention further provides that: the heat source chip should be located under the substrate, and the metal via array, the metal via array and the metal via array are used as thermal conduction vias to conduct the heat of the heat source chip to the linear opening fin type metal heat sink.

To sum up, the present invention has the following beneficial effects:

1. Based on the electrothermal synergy scheme, by optimizing the design of the fin-type metal heat sink structure, a double-ridged waveguide cavity is introduced into the base of the heat dissipation structure as the radiation aperture of the antenna, so that the heat sink itself is designed as an antenna with radiation function The array realizes the conformality of the antenna and the heat dissipation structure, which greatly saves the system space.

2. By introducing a double-ridged waveguide cavity into the fin-type metal heat sink, the form of a linear tapered slot antenna is realized. Compared with the rectangular waveguide, the double-ridged waveguide is its miniaturized structure and has a lower cut-off frequency. The element spacing between arrays is effectively shortened, and the sidelobe level of the pattern is improved.

3. In order to take into account the heat dissipation performance of the antenna, an antenna feed network with a vertical substrate integrated waveguide structure is designed in the substrate, and a large number of metal vias contained therein can be used as thermal vias to conduct heat from the heat source to the fin-type heat sink at the same time. , reducing the design complexity and saving the design cost.

4. The designed heat sink antenna array structure based on the linear tapered slit form, the overall size is no longer limited to the operating frequency and wavelength, and can be well applied to microwave and even millimeter wave frequency bands.

5. In the low temperature co-fired ceramic substrate, the substrate integrated waveguide structure is used as the feeding network of the heat sink antenna, which contains a large number of metallized holes, which can be used as thermal conduction holes to conduct heat from the heat source to the fin type heat sink at the same time. , no additional heat conduction structure is required, the design complexity is reduced, and the design cost is saved.

Description of drawings

FIG. 1 is a schematic structural diagram of a 2×2 heat sink antenna array structure.

FIG. 2 is a schematic structural diagram of a 4×4 heat sink antenna array structure.

FIG. 3 is a schematic structural diagram of a vertical substrate integrated waveguide structure.

Figure 4 is a schematic plan view of a stripline feed input structure.

Figure 5 is a graph showing the variation of the unit gain of the 4×4 heat sink antenna array with the height of the fin.

Figure 6 is a graph showing the variation of the unit gain of the 4×4 heat sink antenna array with the spacing of the fin openings.

Figure 7 is the reflection coefficient curve of the 4×4 heat sink antenna array.

Figure 8 is the gain curve of the 4×4 heat sink antenna array.

Figure 9 is the radiation pattern of the 4×4 heat sink antenna array.

Labels: 1. Heat sink metal base 2, upper metal layer 3, metal via array 4, middle metal layer 5, metal via array 6, lower metal layer 7, metal via array 8, linear opening fin type metal heat dissipation Slice 9, double-ridged waveguide cavity array 10, rectangular aperture array 11, upper dielectric layer 12, rectangular aperture array 13, middle dielectric layer 14, stripline feed input structure 15, rectangular aperture array 16, lower dielectric layer 17, bottom metal layer

Detailed ways

In order to make the technical means, creation features, achievement goals and effects realized by the present invention easy to understand, the present invention will be further described below with reference to the drawings and specific embodiments.

As shown in FIG. 1 , a heat sink antenna array structure based on the form of linear tapered slits proposed by the present invention includes a linear opening fin type metal heat sink 8, a heat sink metal base 1 and a base plate. The upper surface of the base plate is connected to the heat sink. The sheet metal base 1 is connected, and the lower surface of the base plate is connected with the heat source chip. It is characterized in that, the heat sink metal base 1 is provided with a double-ridged waveguide cavity array 9 as an antenna radiation aperture. The double-ridged waveguide cavity array 9 9 is provided with a linear opening fin type metal heat sink 8;

The substrate includes multiple metal layers, a dielectric layer is arranged between the metal layers, and the dielectric layer contains an array of metal vias for forming a substrate-integrated waveguide structure.

The present invention is further provided as follows: the opening size of the double-ridged waveguide cavity array 9 meets the TE10 working mode of the double-ridged waveguide, and each double-ridged waveguide cavity is formed with two adjacent linear opening fin-type metal heat sinks 8 Linear tapered slot antenna.

The present invention is further arranged as follows: the height of the linear opening fin type metal heat sink 8 should be greater than half the working wavelength, the opening size of the linear taper slit should be less than half the working wavelength, and the gap between the fins of the heat sink should be less than one half of the working wavelength. The spacing should not be greater than one working wavelength.

The present invention is further arranged as follows: the substrate is located under the metal base 1 of the heat sink, and includes an upper metal layer 2, an upper dielectric layer 11, an upper metal via array 3, a middle metal layer 4, a middle dielectric layer 13, and a middle metal via The hole array 5, the stripline feed input structure 14, the lower metal layer 6, the lower dielectric layer 16, the lower metal via array 7, and the underlying metal layer 17, wherein,

Upper metal layer 2, upper dielectric layer 11, upper metal via array 3, middle metal layer 4, middle dielectric layer 13, middle metal via array 5, lower metal layer 6, lower dielectric layer 16, lower metal via array 7 , and the underlying metal layer 17 constitutes a vertical substrate integrated waveguide structure;

The heat source chip is located under the substrate, and the upper metal via array 3 , the middle metal via array 5 and the lower metal via array 7 serve as thermal vias to conduct the heat of the heat source chip to the linear opening fin type metal heat sink.

The present invention is further provided as follows: the middle layer metal layer 4, the stripline feeding input structure 14 and the lower layer metal layer 6 constitute a stripline T-type input power distribution and feeding network.

The present invention is further set up as follows: the upper metal layer 2 has an upper rectangular opening array 10, the middle metal layer 4 has a middle rectangular opening array 12, and the lower metal layer 6 has a bottom rectangular opening array 15, which is doubled with the heat sink metal base. Correspondingly, the ridge waveguide cavity array 9 is used as the feeding structure of the heat sink antenna array.

A further arrangement of the present invention is that: the middle dielectric layer 13 is provided with a stripline feed input structure 14 for switching and feeding with the vertical substrate integrated waveguide structure.

The present invention is further configured as follows: the substrate is a low-temperature co-fired ceramic substrate, and more metal vias located outside the substrate integrated waveguide structure can be added to the substrate according to actual needs, thereby increasing the number of thermally conductive vias and reducing The size of the thermal resistance between the heat source chip and the finned heat sink.

Taking the 2×2 heat sink antenna array structure as shown in FIG. 1 as an example, the heat sink antenna array structure in the form of linear tapered slits proposed in this application includes: a heat sink metal base 1 and a substrate, and the heat sink metal base is provided with A plurality of groups of double-ridged waveguide cavities are arranged in an array 9, and a linear opening fin-type metal heat sink 8 is arranged on the double-ridged waveguide cavity array 9, and each double-ridged waveguide cavity is connected to two adjacent linear openings. The heat sink 8 constitutes a linear tapered slot antenna. The substrate includes an upper metal layer 2 , an upper dielectric layer 11 , a middle metal layer 4 , a middle dielectric layer 13 , a lower metal layer 6 , and a lower dielectric layer 16 , which are arranged in order from top to bottom. and the bottom metal layer 17, the upper metal layer 2 is provided with an upper rectangular opening array 10, the upper dielectric layer 11 is provided with an upper metal via array 3, and the middle metal layer 4 is provided with a middle rectangular opening array 12. The middle-layer dielectric layer 13 is provided with a middle-layer metal via array 5 and a stripline feed input structure 14, the lower-layer metal layer 6 is provided with a bottom rectangular opening array 15, and the lower-layer dielectric layer 16 is provided with There is an underlying metal via array 7 .

In the specific implementation process, this embodiment provides a design scheme of a 4×4 heat sink antenna array, as shown in FIG. 2 , and the operating frequency is 28 GHz. The linear opening fin type metal heat sink 8 is processed by 3D printing technology, and the upper dielectric layer 11 , the middle dielectric layer 13 and the lower dielectric layer 16 are processed by a low temperature co-fired ceramic process. In this embodiment, the dielectric constant of the low temperature co-fired ceramic substrate is 5.9, the loss tangent is 0.002, and the geometric size is 30mm×40mm×0.96mm. The plane size of the heat sink metal base 1 is 30mm×40mm, and the thickness of the heat sink metal base 1 is 1mm. According to actual needs, if the operating frequency is changed, the dimensions of the heat sink and the dielectric plate are also changed accordingly.

As shown in Figure 2, a 4×4 double-ridged waveguide cavity array is opened on the metal base 1 of the heat sink. In the TE10 working mode of the double-ridged waveguide, the width of the linear open fin type metal heat sink 8 is 1.2mm, the height is 10mm, the length of the upper side is 2.9mm, the length of the lower side is 5mm, and the fin spacing is 5.4mm.

As shown in FIG. 2, upper metal layer 2, upper dielectric layer 11, upper metal via array 3, middle metal layer 4, middle dielectric layer 13, middle metal via array 5, lower metal layer 6, lower dielectric layer 16, The lower metal via array 7 and the bottom metal layer 17 constitute a vertical substrate integrated waveguide structure, the size of the waveguide is 4.6mm×2.6mm; the upper metal layer 2 has the upper rectangular opening array 10, and the middle metal layer 4 has the middle rectangular opening The array 12 has a bottom rectangular opening array 15 in the lower metal layer 6, which corresponds to the double-ridged waveguide cavity array 9 on the metal base of the heat sink, and is used as the feeding structure of the heat sink antenna array. The feed transfer for the excitation of the antenna array, the size of the rectangular opening is 4mm × 2mm.

FIG. 3 is a schematic plan view of the vertical substrate integrated waveguide structure shown in FIG. 2 .

4 is a schematic plan view of the stripline feed input structure 14; in this embodiment, a T-type input power distribution network is used, and other power structures such as a Y-type power distribution network can also be selected according to actual needs.

As shown in FIG. 4 , the switching feed between the stripline feed input structure 14 and the vertical substrate integrated waveguide structure is realized by using the probe-type structure. According to actual needs, other transfer methods such as slot coupling can also be selected.

FIG. 5 is a graph showing the variation of the unit gain of the 4×4 heat sink antenna array with the height of the fins. It can be seen that when the height of the fin does not exceed one working wavelength, increasing the height of the fin can improve the gain of the antenna array.

FIG. 6 is a graph showing the variation curve of the unit gain of the 4×4 heat sink antenna array with the fin spacing. It can be seen that, when the fin spacing is not more than a quarter of the working wavelength, increasing the opening spacing of the fins can improve the gain of the antenna array.

FIG. 7 shows the reflection coefficient of the 4×4 heat sink antenna array structure, the 10dB impedance bandwidth is 3.25GHz (from 26.25GHz to 29.50GHz), and the relative bandwidth is 11.6%.

Figure 8 is the gain curve of the 4×4 heat sink antenna array structure, the gain is 16.47dBi at the operating frequency, the maximum gain is 16.87dBi (at 29.5GHz), and within the 10dB impedance bandwidth (from 26.25GHz to 29.50GHz) Gain is flat.

FIG. 9 is a radiation pattern of the 4×4 heat sink antenna array structure, and the 3dB main lobe beam widths on the E plane and the H plane are 24° and 25°, respectively.

In the description of the present invention, it should be noted that the orientations or positional relationships indicated by the terms "upper", "lower", "inner", "outer", "left", "right", etc. are based on those shown in the accompanying drawings. The orientation or positional relationship, or the orientation or positional relationship that the product of the invention is usually placed in use, or the orientation or positional relationship that is commonly understood by those skilled in the art, are only for the convenience of describing the present invention and simplifying the description, rather than indicating or It is implied that the device or element referred to must have a particular orientation, be constructed and operate in a particular orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first", "second", etc. are only used to differentiate the description and should not be construed to indicate or imply relative importance. In the description of the present invention, it should also be noted that, unless otherwise expressly specified and limited, terms such as "arrangement" and "connection" should be understood in a broad sense, for example, "connection" may be a fixed connection or Detachable connection, or integral connection; may be mechanical connection or electrical connection; may be direct connection or indirect connection through an intermediate medium, and may be internal communication between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations. As used herein, the terms "comprising", "comprising" or any other variation thereof are intended to encompass non-exclusive inclusion, in addition to those elements listed, but also other elements not expressly listed.

The foregoing has shown and described the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above-mentioned embodiments. The above-mentioned embodiments and descriptions only illustrate the principle of the present invention. Such changes and improvements fall within the scope of the claimed invention. The claimed scope of the present invention is defined by the appended claims and their equivalents.

Claims (9)

1. A heat sink antenna array structure based on a linear tapered slot form, comprising a double ridge waveguide cavity array (9), a linear opening fin type metal heat sink (8), a heat sink metal base (1) and a substrate, The upper surface of the base plate is connected to the heat sink metal base (1), and the lower surface of the base plate is connected to the heat source chip, characterized in that the heat sink metal base (1) is provided with a linear opening fin type metal heat sink (8) For guiding the radiation of electromagnetic waves, the bottom of the linear opening fin type metal heat sink (8) extends to the inside of the cavity of the metal base (1) of the heat sink, forming a double-ridged waveguide cavity array (9) serving as an antenna radiation aperture ), which is used to realize the miniaturization of the antenna array and improve the antenna radiation performance; The substrate includes multiple metal layers, a dielectric layer is arranged between the metal layers, and the dielectric layer contains an array of metal vias for forming a substrate-integrated waveguide structure. 2 . The heat sink antenna array structure based on the linear tapered slot form according to claim 1 , wherein the size of the opening of the double-ridged waveguide cavity array (9) satisfies the TE10 working mode of the double-ridged waveguide. 3 . , each double-ridged waveguide cavity and two adjacent linear opening fin-type metal heat sinks (8) form a linear tapered slot antenna. 3. A kind of radiating fin antenna array structure based on linear tapered slit form according to claim 1, is characterized in that, the height of described linear opening fin type metal radiating fin (8) should be greater than half work The size of the opening of the linear taper slit should be less than one-half of the working wavelength, and the spacing between the fins of the heat sink should not be greater than one working wavelength. 4. A heat sink antenna array structure based on a linear tapered slot form according to claim 1, characterized in that, the substrate is located below the heat sink metal base (1), comprising: an upper metal layer (2), an upper dielectric layer (11), a middle metal layer (4), a middle dielectric layer (13), a lower metal layer (6), a lower dielectric layer (16), and a bottom metal layer (17), in, Upper metal layer (2), upper dielectric layer (11), upper metal via array (3), middle metal layer (4), middle dielectric layer (13), middle metal via array (5), lower metal layer ( 6), the lower dielectric layer (16), the lower metal via array (7), and the underlying metal layer (17) constitute a vertical substrate integrated waveguide structure. 5. A heat sink antenna array structure based on a linear tapered slot form according to claim 4, characterized in that the middle metal layer (4), the stripline feed input structure (14) and the lower metal layer ( 6) A stripline T-type input power distribution feeder network is formed. 6. A kind of radiating fin antenna array structure based on linear tapered slot form according to claim 4, it is characterized in that, upper layer metal layer (2) has upper layer rectangular opening array (10), middle layer metal layer (4) There is a middle-layer rectangular opening array (12), and a bottom-layer rectangular opening array (15) in the lower metal layer (6), which corresponds to the double-ridged waveguide cavity array (9) on the metal base of the heat sink, and serves as a feed for the heat sink antenna array. electrical structure. 7 . The heat sink antenna array structure based on the linear tapered slot form according to claim 4 , wherein the middle dielectric layer ( 13 ) is provided with a structure for switching between the integrated waveguide structure with the vertical substrate. 8 . A stripline feed input structure (14) is connected to the feed. 8 . The heat sink antenna array structure according to claim 1 , wherein the substrate is a low-temperature co-fired ceramic substrate. 9 . 9. A heat sink antenna array structure according to any one of claims 1 to 8, characterized in that the heat source chip should be located under the substrate, the metal via array (3), the metal via array (5) and the metal via The via hole array (7) serves as a thermally conductive through hole to conduct the heat of the heat source chip to the linear opening fin type metal heat sink (8).

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