CN-122029697-A - Antenna unit

Abstract

An antenna unit including an antenna capable of transmitting and receiving radio waves of a predetermined frequency band, the antenna including a conductor layer formed on a substrate extending in a first direction, and a first antenna and a second antenna capable of transmitting and receiving polarized waves different from each other, the first antenna being fed from one end and the other end being open-circuited, the second antenna being fed from one end and the other end being electrically connected to a ground region, the first antenna and the second antenna being formed in a central region of the substrate along the first direction.

Inventors

• MATSUSHIMA MASAKI
• HIDEYUKL KANIE
• SUGIMURA KAZUNORI
• Tokuyama Kanya
• NIWA HIDEYUKI

Assignees

• 株式会社爱信

Dates

Publication Date

20260512

Application Date

20240731

Priority Date

20231018

Claims (6)

1. 1. An antenna unit comprising an antenna capable of transmitting and receiving radio waves of a predetermined frequency band, The antenna has a first antenna and a second antenna which are formed on a conductor layer of a substrate extending in a first direction and are capable of transmitting and receiving polarized waves different from each other, The first antenna is powered from one end, and the other end is open, The second antenna is powered from one end, and the other end is electrically connected to the ground area, The first antenna and the second antenna are formed in a central region of the substrate along the first direction.
2. 2. The antenna element of claim 1, wherein, The antenna and the two ends of the grounding area along the first direction are separated by more than 1/10 of the wavelength of the electric wave.
3. 3. An antenna unit according to claim 1 or 2, wherein, The substrate has a removing portion from which the conductor layer is removed, the removing portion being provided in an entire region of a lower layer of each of the first antenna and the second antenna, The removing portion is provided at an outer edge portion of the substrate.
4. 4. An antenna unit according to claim 1 or 2, wherein, The antenna is provided with an impedance adjustment unit that adjusts impedance.
5. 5. An antenna unit according to claim 1 or 2, wherein, The length of the substrate along a second direction orthogonal to the first direction is 1/3 or less of the wavelength of the radio wave.
6. 6. An antenna unit according to claim 1 or 2, wherein, The frequency band is in the range of 2.4GHz to 2.5 GHz.

Description

Antenna unit Technical Field The present invention relates to an antenna unit including an antenna capable of transmitting and receiving radio waves in a predetermined frequency band. Background Conventionally, antennas have been used for transmitting and receiving radio waves. As a technique for such an antenna, there is an antenna module described in patent document 1, for example. The antenna module described in patent document 1 (corresponding to the "antenna unit" of the present application) has a first antenna and a second antenna as antennas. These antennas are configured in a so-called inverted F shape, and the power supply portion is electrically connected to the power supply portion by capacitive coupling. Prior art literature Patent literature Patent document 1 Japanese patent application laid-open No. 2023-104765. Problems to be solved by the invention In the antenna module described in patent document 1, the first antenna and the second antenna are disposed in a state inclined by 90 degrees with respect to each other. In this case, in order to transmit and receive polarized waves different from each other, a substrate having an aspect ratio close to 1 needs to be used. Therefore, the substrate of the antenna module described in patent document 1 has a square shape, and there is room for improvement in downsizing of the substrate. Therefore, an antenna unit capable of miniaturization is demanded. Disclosure of Invention Means for solving the problems The antenna unit according to the present invention is characterized by comprising an antenna capable of transmitting and receiving radio waves of a predetermined frequency band, the antenna comprising a first antenna and a second antenna which are formed on a conductor layer of a substrate extending in a first direction and are capable of transmitting and receiving polarized waves different from each other, the first antenna being supplied with power from one end and open at the other end, the second antenna being supplied with power from one end and electrically connected to a ground region at the other end, the first antenna and the second antenna being formed in a central region of the substrate along the first direction. With such a characteristic configuration, the first antenna is formed in the central region of the substrate in the first direction, and is supplied with power from one end and the other end is opened, so that polarized waves in a direction orthogonal to the first direction can be transmitted and received. Further, the second antenna is formed in the central region of the substrate in the first direction, and is fed from one end and the other end is electrically connected to the ground region, so that transmission and reception of polarized waves in the first direction can be performed. In addition, in such a configuration, the length of the substrate in the direction orthogonal to the first direction is not particularly limited, and thus the substrate can be miniaturized. Drawings Fig. 1 is a top view of a unit of an antenna. Fig. 2 is an enlarged view of the first antenna. Fig. 3 is an enlarged view of the second antenna. Fig. 4 is a plan view of the antenna unit in the case where the position of the antenna is changed. Detailed Description The antenna unit according to the present disclosure includes an antenna capable of transmitting and receiving radio waves in a predetermined frequency band, and is capable of transmitting and receiving polarized waves different from each other. The antenna unit 1 of the present embodiment will be described below. However, the antenna unit 1 is not limited to the following embodiments, and various modifications can be made without departing from the gist thereof. Fig. 1 is a top view of a unit 1 of an antenna. Fig. 2 is an enlarged view of the first antenna 11, and fig. 3 is an enlarged view of the second antenna 12. As shown in fig. 1, the antenna unit 1 includes an antenna 10, a removing unit 20, an impedance adjusting unit 30, and a control unit 40. The antenna 10 has a first antenna 11 and a second antenna 12. The antenna 10 can receive an air-borne radio wave, convert the radio wave into an electric signal, transmit the electric signal to the control unit 40, and can cause the radio wave on which the electric signal output from the control unit 40 is superimposed to propagate in the air. The antenna 10 is formed on a conductor layer of the substrate 2 extending along the first direction. The substrate 2 of the present embodiment is formed of a rectangular shape having a long side along a first direction and a short side along a second direction orthogonal to the first direction as shown in fig. 1 in a plan view. The antenna 10 is formed by patterning a conductor layer on the surface layer of the rectangular substrate 2. The substrate 2 corresponds to a printed circuit board in which conductor layers made of a conductor such as copper foil and insulating layers made of an insulating ma