A flexible lightweight array antenna with integrated feed network and antenna

Abstract

This invention discloses a flexible, lightweight array antenna integrating a feed grid and an antenna, comprising a radiating layer, a supporting layer, a reflective layer, a printed circuit board layer, a feed line layer, and a feeding structure. The supporting layer of the antenna is made of partially hollowed-out foam, which is lightweight. The radiating layer, reflective layer, and feed line layer of the antenna are all thin metal layers, with the radiating layer and reflective layer attached to both sides of the supporting layer. The reflective layer and feed line layer are attached to both sides of the printed circuit board layer. This antenna can be flexibly attached to curved surfaces and can be effectively applied to flexible and conformal applications. It can also be used as a phased array unit.

Description

Technical Field

[0001] This invention relates to the field of microwave antenna technology, and in particular to a flexible and lightweight array antenna that integrates a feed grid and an antenna. Background Technology

[0002] With the development of flexible electronics technology, extremely high requirements have been placed on the conformal bearing capacity and mechanical flexibility of antennas. Therefore, flexible patch antennas have become an important research direction. Existing flexible antenna designs are mostly implemented on flexible substrates of conventional thickness (e.g., 0.5 mm or more). Although they possess a certain degree of bending capability, their profile height, weight, and bending adaptability under small radii of curvature are still not ideal. Especially when implementing multi-feed point or array designs to improve gain and beam performance, traditional microstrip power dividers introduce significant losses and are not conducive to ultra-thin structure designs. Therefore, highly integrated flexible and lightweight antennas have broad application prospects. Summary of the Invention

[0003] To address the shortcomings of the aforementioned background technology, the present invention aims to provide a flexible and lightweight array antenna integrating a feed grid and an antenna. This antenna aims to solve the following problems: achieving array flexibility using a 0.1mm dielectric substrate in the feed layer; using a near-coplanar waveguide instead of microstrip / strip lines to reduce the breakage risk and high transmission loss associated with excessively thin feed lines; and employing a slot-fed patch antenna that integrates a 1-to-4 power divider with the antenna, resulting in a simple structure and convenient fabrication.

[0004] This invention is achieved through the following scheme: A flexible and lightweight array antenna integrating a feed grid and an antenna includes a radiating layer, a supporting layer, a reflective layer, a printed circuit board layer, a feed line layer, and a feeding structure; wherein the radiating layer is bonded to the upper surface of the supporting layer; the reflective layer covers the upper surface of the printed circuit board layer, and the feed line layer covers the lower surface of the printed circuit board layer; the supporting layer is disposed on the upper surface of the reflective layer; and the feeding structure is connected to the main port of the feed line layer.

[0005] Preferably, the radiating layer is a 25µm polyimide copper-clad film; the support layer is made of foam material with a rectangular groove cut into its bottom; the printed circuit board layer has a thickness of 0.1mm and a dielectric constant of 3.

[0006] Preferably, the reflective layer is a metal layer with etched gaps, including I-shaped gaps, feeder gaps, and feeder gap partitions; wherein the I-shaped gaps and feeder gaps are formed by etching away the metal layer at designated locations; and the metal on both sides of the feeder gaps are connected at regular intervals along the feeder gaps to form feeder gap partitions.

[0007] Preferably, the total length of the I-shaped gap is about 0.5 working wavelengths, the width of the feeder gap is 2mm, and the certain distance is 0.1 working wavelengths.

[0008] Preferably, the printed circuit board layer, the feeder layer, and the reflector layer together form a one-to-four power divider based on a coplanar waveguide, with energy coupled from the end of the feeder layer to the radiating layer through an I-shaped gap.

[0009] Preferably, the line length and line width of the 1-to-4 power divider are set according to the theoretical values ​​of the T-type power divider.

[0010] Preferably, the power supply structure includes pads, a metal housing, and a metal probe. The pads are used to fix the power supply structure, the metal housing is used to protect the metal probe, one end of the metal probe is electrically connected to the feed layer, and the other end is connected to an external RF cable or connector.

[0011] Preferably, the array antenna can be conformally attached to a curved carrier.

[0012] Preferably, the size of the I-shaped gap is determined by electromagnetic simulation.

[0013] Compared with the prior art, the significant advantages of this invention are: 1. The antenna of the present invention uses a 0.1mm printed circuit board layer, and the hollowed-out support layer can achieve the requirement of lightweight antenna.

[0014] 2. The antenna of this invention uses a 1-to-4 power divider based on a quasi-coplanar waveguide for feeding. The quasi-coplanar waveguide structure, by introducing a defective ground structure, increases the feed line width and improves the structural strength of the metal feed line layer under bending conditions. Combined with a 0.1mm printed circuit board layer, this further improves the antenna's flexibility. The use of the power divider can reduce the number of channels by 75%, reduce the number of components at the antenna's rear end, and thus achieve weight reduction for the entire system. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of a flexible, lightweight array antenna integrating a feed grid and an antenna according to the present invention.

[0016] Figure 2 This is a side view of a flexible, lightweight array antenna integrating a feed grid and an antenna according to the present invention.

[0017] Figure 3 This is a top view of a flexible, lightweight array antenna integrating a feed grid and an antenna according to the present invention.

[0018] Figure 4 This is a schematic diagram of a 1-to-4 power divider.

[0019] Figure 5 This is a schematic diagram of the power supply structure.

[0020] Figure 6 This is a schematic diagram of the antenna of the present invention assembled on a curved surface. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings.

[0022] like Figure 1 and Figure 2 As shown, the array antenna (1) of the present invention has a five-layer structure, namely a radiating layer (2), a support layer (3), a reflective layer (4), a printed circuit board layer (5), and a feeder layer (6). The radiating layer (2) is made of 25 μm polyimide copper-clad film and is bonded to the upper surface of the support layer (3); the support layer (3) is made of foam material and a rectangular groove is dug at the bottom to achieve weight reduction and flexibility; the reflective layer (4) and the feeder layer (6) cover the upper and lower surfaces of the printed circuit board layer (5), the printed circuit board layer (5) has a thickness of 0.1 mm and a dielectric constant of 3.

[0023] like Figure 3 As shown, the unit size is 0.73*0.5 working wavelengths. The support layer (3) is made of foam material and its height is about 0.06 times the working wavelength. Its size is consistent with that of the radiation layer (2), which is about 0.38*0.32 working wavelengths. In order to reduce weight and improve flexibility, six rectangular grooves are dug in the lower half of the support layer (3) with a height of 0.036 times the working wavelength, but they are not connected vertically. The support layer (3) close to the radiation layer (2) is a complete foam to ensure that the height of the radiation layer (2) is consistent. The reflective layer (4) is a metal layer with etched gaps, located on the upper layer of the printed circuit board layer (5), including an I-shaped gap (7), a feed line gap (8) and a feed line gap partition (9). The I-shaped gap (7) and the feed line gap (8) are formed by etching away metal at a specified position. The total length of the I-shaped gap (7) is about 0.5 wavelengths, and the width of the feed line gap (8) is 2 mm. In order to reduce the cross polarization of the antenna, the metal on both sides is connected every 0.1 working wavelengths along the feed line gap (8), which is the feed line gap partition (9).

[0024] like Figure 4 As shown, the printed circuit board layer (5) is 0.1 mm thick, and together with the feeder layer (6) and the reflector layer (4), it forms a 1-to-4 power divider based on a coplanar waveguide. In order to reduce solder joints, a slot coupling feed is adopted, and energy is coupled from the end of the feeder layer (6) to the radiating layer (2) through the I-shaped slot (7). The line length and line width of the 1-to-4 power divider are set according to the theoretical values ​​of the T-section power divider.

[0025] like Figure 5As shown, the feeding structure (10) of the antenna (1) is located at the starting point of the feed layer (6). The feeding structure (10) includes a pad (11), a metal shell (12), and a metal probe (13). One end of the metal probe (13) is electrically connected to the feed layer (6), and the other end is connected to an external radio frequency cable or connector.

[0026] like Figure 6 The antenna (1) of the present invention shown can be conformally attached to a curved carrier. The radius of the curved surface of the carrier can be as small as 1.25 times the wavelength.

[0027] The specific embodiments described herein are merely illustrative of the spirit of the invention. Those skilled in the art to which this invention pertains may make various modifications, additions, or similar substitutions to the described specific embodiments without departing from the spirit of the invention or exceeding the scope defined by the appended claims.

Claims

1. A flexible, lightweight array antenna integrating a feed grid and an antenna, characterized in that, It includes a radiating layer (2), a supporting layer (3), a reflective layer (4), a printed circuit board layer (5), a feeder layer (6), and a power supply structure (10); wherein, the radiating layer (2) is bonded to the upper surface of the supporting layer (3); the reflective layer (4) covers the upper surface of the printed circuit board layer (5), and the feeder layer (6) covers the lower surface of the printed circuit board layer (5); the supporting layer (3) is disposed on the upper surface of the reflective layer (4); and the power supply structure (10) is connected to the main port of the feeder layer (6).

2. The array antenna according to claim 1, characterized in that, The radiation layer (2) is made of 25µm polyimide copper-clad film; the support layer (3) is made of foam material and has a rectangular groove dug at the bottom; the printed circuit board layer (5) has a thickness of 0.1mm and a dielectric constant of 3.

3. The array antenna according to claim 1, characterized in that, The reflective layer (4) is a metal layer with etched gaps, including an I-shaped gap (7), a feed line gap (8) and a feed line gap partition (9); wherein the I-shaped gap (7) and the feed line gap (8) are formed by etching away the metal layer at a specified position; the metal on both sides of the gap is connected at certain intervals along the feed line gap (8) to form the feed line gap partition (9).

4. The array antenna according to claim 3, characterized in that, The total length of the I-shaped gap (7) is about 0.5 working wavelengths, the width of the feeder gap (8) is 2mm, and the certain distance is 0.1 working wavelengths.

5. The array antenna according to claim 3, characterized in that, The printed circuit board layer, the feeder layer (6), and the reflector layer (4) together form a one-to-four power divider based on a coplanar waveguide. Energy is coupled from the end of the feeder layer (6) to the radiation layer (2) through the I-shaped gap (7).

6. The array antenna according to claim 5, characterized in that, The line length and line width of the 1-to-4 power divider are set according to the theoretical values ​​of the T-type power divider.

7. The array antenna according to claim 1, characterized in that, The power supply structure (10) includes a pad (11), a metal shell (12) and a metal probe (13). The pad (11) is used to fix the power supply structure (10), and the metal shell (12) is used to protect the metal probe (13). One end of the metal probe (13) is electrically connected to the feed layer (6), and the other end is connected to an external RF cable or connector.

8. The array antenna according to claim 1, characterized in that, The array antenna can be conformally attached to a curved carrier.

9. The array antenna according to claim 3, characterized in that, The size of the I-shaped gap (7) was determined by electromagnetic simulation.

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