JPH10200326A - Antenna device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize an inter-high transmission and reception antenna isolation low attitude antenna system. SOLUTION: This device is adjusted so that the minimum neighborhood field directions of a circular patch antenna 1 for reception and a circular patch antenna 2 for transmission arranged as reception and transmission antennas formed through a dielectric 3 on the same plane ground conductor 4 can be made almost correspond to angles Φr and Φt made by feeding points 5a and 6a among orthogonal two feeding points 5a/5b and 6a/6b receiving a power in those circular patch antennas 1 and 2 and straight lines passing through the central positions of the antennas 1 and 2. Only a right-hand polarized wave is outputted through a 90 hybrid 7a to a receiver 8 for a received signal by the circular patch antenna 1 for reception. A transmitted signal by a transmitter 9 is radiated through a 90 hybrid 7b from the circular patch antenna 2 for transmission as the right-hand polarized wave.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a low-profile antenna apparatus which is applied to a communication / radar or the like and has a high isolation between transmitting and receiving antennas.

[0002]

2. Description of the Related Art For example, a document (Chujo W. eta)
l: A two-layer self-diplex
ing antenna using a circular
large polarized ring patc
hantenna, IEICE Trans. Vo
l. E 74, No10, pp. 3261-3267,
Oct. 1991) has a two-layer self-demultiplexing antenna (two-layer) having a structure in which a transmitting circular patch antenna 17 is superimposed on a receiving circular patch antenna 16 as shown in FIG.
A self-diplexing antenna is adopted.

[0003]

The above-mentioned conventional transmission / reception separating antenna apparatus employs a two-layer self-demultiplexing antenna system. Therefore, when receiving and transmitting isotropically polarized waves, a transmitting antenna is used. The radio wave appears to be a counter-rotating circularly polarized wave to the receiving antenna, and the isolation between the transmitting and receiving antennas is high, but the antenna device has a high attitude. When receiving and transmitting antennas having opposite circularly polarized waves, the transmitting antenna radio wave appears to be the same circularly polarized wave to the receiving antenna, and there is a problem in that the antenna device has a high attitude with poor isolation between the transmitting and receiving antennas.

A problem to be solved by the present invention is to provide a microstrip patch antenna for receiving and transmitting circularly polarized waves so as to maintain the whole antenna in a low attitude and to increase the isolation between the transmitting and receiving antennas. Are arranged as receiving and transmitting and receiving antennas formed on a ground conductor such as a plane, and have a structure in which the vertical axis is rotated by a specific angle so that the isolation between the transmitting and receiving antennas is almost maximized (high isolation between the transmitting and receiving antennas). Low-profile antenna system).

[0005]

The antenna apparatus according to the present invention is characterized in that the following means are provided to solve the above-mentioned problems, and the antenna apparatus employs a high-transmitting / receiving antenna-isolation low-profile antenna system.

The transmitting and receiving microstrip antennas perform circularly polarized wave excitation, are arranged as transmitting and receiving antennas formed on a plane, polyhedral or curved ground conductor, and provide isolation between the transmitting and receiving antennas. Is rotated by a specific angle with respect to the vertical axis of the transmitting and receiving antenna patch planes so as to substantially maximize. Alternatively, a block-shaped conductor or a block-shaped dielectric having a different dielectric constant from the dielectric forming the transmission and reception antenna is separately arranged between the transmission and reception antennas.
Alternatively, a plurality of types of block-shaped dielectrics having different dielectrics between the transmitting and receiving antennas are periodically arranged separately at predetermined intervals. Alternatively, instead of the common ground conductor forming the transmitting and receiving antennas, they are individually used without being connected to each other as dedicated ground conductors for the transmitting and receiving antennas. Alternatively, slots are separately arranged on the ground conductor between the transmitting and receiving antennas. Alternatively, a resistive element is separately loaded in the arrangement slot of the ground conductor between the transmitting and receiving antennas.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIG. 1, in a separate transmitting and receiving antenna apparatus according to an embodiment of the present invention, annular patch antennas 1 and 2 for receiving and transmitting are arranged on a ground conductor 4 on the same plane. Are arranged as receiving and transmitting antennas formed through a dielectric 3. Power is supplied from feed points 5a and 5b and 6a and 6b which are orthogonal to each other, and an angle φ between the feed points 5a and 6a and a straight line passing through the center position of the receiving and transmitting annular patch antennas 1 and 2 Ring patch antenna 1 for reception and transmission for _r and φ _t
And 2 are adjusted so that the minimum near-field directions are substantially opposed to each other. The receiving annular patch antenna 1 outputs only the right-handed circularly polarized wave to the receiver 8 via the 90 ° hybrid 7a with respect to the received signal. The transmission ring patch antenna 2 radiates the transmission signal from the transmitter 9 as right-handed circularly polarized light via the 90 ° hybrid 7b. The antenna device can be kept in a low attitude, and the isolation between the receiving and transmitting annular patch antennas 1 and 2 can be increased.

In the transmission / reception separating antenna device of the above embodiment, the reception and transmission microstrip patch antennas for circularly polarized wave excitation are arranged as reception and transmission antennas formed on a plane conductor such as a plane via a dielectric. In addition, a system having a structure in which the vertical axis is rotated by a specific angle so as to substantially maximize the isolation between the transmitting and receiving antennas (high-isolation between the transmitting and receiving antennas and a low-profile antenna system) is adopted.

In the embodiment of the present invention shown in FIG. 1, as shown in FIG. 2 or FIG. 3, for example, a rectangular parallelepiped metal (there is no particular shape restriction) between the receiving and transmitting annular patch antennas 1 and 2. A dielectric 11 having a dielectric constant different from that of the conductor 10 or the dielectric 3 is separately arranged, and a radio wave propagating in the dielectric 3 radiated from the ring antenna for transmission 2 is reflected and scattered by the metal conductor 10 and received. Ring patch antenna 1
Propagation in the direction may be suppressed. The isolation between the transmitting and receiving antennas can be made higher.

In the embodiment of the invention shown in FIG. 1, as shown in FIG. 4, receiving and transmitting annular patch antennas 1 and 2 are used.
For example, two (or three or more) rectangular parallelepiped dielectrics 12a and 12b having mutually different dielectric constants are separately arranged periodically at an interval L, and dielectrics radiated from the transmitting annular patch antenna 2 are provided. 3. The radio wave radiated from the ring patch antenna 1 or 2 for reception or transmission is repeatedly transmitted and reflected at the boundary between the dielectrics 12a and 12b with respect to the medium-propagating radio wave, and the propagation direction of the leaky wave radiating a part of the radio wave is transmitted into space. The arrangement period may be adjusted so as to be substantially closer to the direction A or B, and propagation in the direction of the receiving annular patch antenna 1 may be suppressed.
The isolation between the transmitting and receiving antennas can be made higher.

In the embodiment of the invention shown in FIG. 1, the receiving and transmitting toroids forming the receiving and transmitting toroidal patch antennas 1 and 2 are replaced with the receiving and transmitting toroids as shown in FIG. The patch antennas 1 and 2 are individually used as dedicated ground conductors 13a and 13b without being connected to each other, and scatter the radio wave radiated by the transmitting annular patch antenna 2 at the edge of the ground conductor 13b, and partially use the patch for reception. Leakage may be made to leak to the rear surfaces of the transmitting annular patch antennas 1 and 2 so that propagation in the direction of the receiving annular patch antenna 1 may be suppressed. The isolation between the transmitting and receiving antennas can be made higher.

In the embodiment of the invention shown in FIG. 1, as shown in FIG. 6, receiving and transmitting annular patch antennas 1 and 2 are used.
Slots 14 are separately arranged in the ground conductor 4 between them, and the radio wave propagating in the dielectric 3 radiated from the transmitting annular patch antenna 2 is coupled to the slot 14 and radiated above and below the ground conductor 4, and the receiving circle is formed. Propagation in the direction of the ring patch antenna 1 may be suppressed. The isolation between the transmitting and receiving antennas can be increased.

In the embodiment of the invention shown in FIG. 6, as shown in FIG. 7, receiving and transmitting annular patch antennas 1 and 2 are used.
A resistive element 15 is separately loaded in the array slot 14 of the interstellar conductor 4, and the coupling power of the slot 14 for the radio wave propagating in the dielectric 3 radiated from the transmitting annular patch antenna 2 is consumed by the resistive element, and Propagation in the direction of the annular patch antenna 1 may be suppressed. The isolation between the transmitting and receiving antennas can be increased, and unnecessary radiation by the slot 14 can be reduced.

In the embodiments of the present invention shown in FIGS. 1 to 7, the receiving and transmitting annular patch antennas 1 and 2 have been described as being formed with the dielectric 3 interposed therebetween. It may be formed. Get the same effect.

In the embodiment of the invention shown in FIGS. 1 to 7, the 90 ° hybrids 7a and 7b reduce the excitation phase difference between two orthogonal feeding points of the receiving and transmitting annular patch antennas 1 and 2 to 90 °. However, it is needless to say that any circuit may be used as long as the circuit divides the input power into two and outputs an excitation phase difference of 90 °.

In the embodiments of the present invention shown in FIGS. 1 to 7, it has been described that both the receiving and transmitting annular patch antennas 1 and 2 excite right-handed circularly polarized wave excitation. Polarization excitation may be performed. Further, the receiving annular patch antenna 1 may perform right or left circularly polarized wave excitation, and the transmitting circular patch antenna 2 may perform left or right circularly polarized wave excitation. Get the same effect.

In the embodiment of the invention shown in FIGS. 1 to 7, the receiving and transmitting annular patch antennas 1 and 2 are orthogonal to each other.
Although it has been described that circularly polarized wave excitation is performed by point feeding, a degenerate separation type annular patch antenna that performs circularly polarized wave excitation by one point feeding may be used. Get the same effect.

In the embodiments of the present invention shown in FIGS. 1 to 7, the ring patch antennas 1 and 2 for reception and transmission have been described as using microstrip patch antennas in the basic mode as reception and transmission antennas. It goes without saying that a higher-order mode microstrip patch antenna may be used.

Although the embodiments of the invention shown in FIGS. 1 to 7 have been described assuming that the receiving and transmitting annular patch antennas 1 and 2 are arranged on the same plane, they are arranged on a polyhedron or an arbitrary curved surface. They may be arranged. Get the same effect.

[0020]

According to the antenna apparatus of the present invention as described above, the receiving and transmitting microstrip antennas for exciting circularly polarized waves are arranged as receiving and transmitting antennas formed on a ground conductor such as a plane, and the transmitting and receiving antennas are arranged. Since the system has a structure in which the vertical axis is rotated by a specific angle so as to maximize the isolation between the antennas, it has a structure in which a transmitting circular patch antenna is superimposed on a receiving circular patch antenna as in the past. Compared with the two-layer self-demultiplexing antenna system, there is an effect that the antenna device can be kept in a low attitude, the isolation between the transmitting and receiving antennas can be increased, and the isolation between the transmitting and receiving antennas can be further increased for each invention.

[Brief description of the drawings]

1A and 1B are a front view and a cross-sectional view, respectively, of a configuration of a transmission / reception separated antenna device according to an embodiment of the present invention.

FIGS. 2A and 2B are a front view and a cross-sectional view, respectively, showing another embodiment of the present invention.

FIGS. 3A and 3B are a front view and a cross-sectional view, respectively, showing another embodiment of the present invention.

FIG. 4 is a configuration front view and a cross-sectional view showing another embodiment of the present invention.

FIGS. 5A and 5B are a front view and a cross-sectional view, respectively, illustrating another embodiment of the present invention.

FIGS. 6A and 6B are a front view and a cross-sectional view, respectively, showing another embodiment of the present invention.

FIGS. 7A and 7B are a front view and a cross-sectional view, respectively, showing another embodiment of the present invention.

FIG. 8 is an overall configuration diagram of a transmission / reception separating antenna device showing a conventional technique, and a front view and a cross-sectional view of the configuration of a ring patch antenna for reception and a circular patch antenna for transmission.

[Explanation of symbols]

1 ring patch antenna for reception, 2 ring patch antenna for transmission, 3 dielectric, 4 ground conductor, 5 feeding point for ring patch antenna for reception, 6 feeding point for ring patch antenna for transmission, 790 ° hybrid , 8 Receiver, 9
Transmitter, 10 metal conductor, 11 Dielectric having different dielectric constant from dielectric 3, 12 Dielectric having different dielectric constant from each other, 13 Ground conductor for ring patch antenna for reception and transmission, 14 Slot, 15 Resistive element. In the drawings, the same reference numerals indicate the same or corresponding parts.

Claims (6)

[Claims] 1. A vertical axis of a transmitting and receiving antenna patch plane arranged as transmitting and receiving antennas formed on a plane, polyhedron or curved ground conductor, and so as to substantially maximize the isolation between the transmitting and receiving antennas. An antenna device having transmission and reception microstrip antennas each having a structure for rotating by a specific angle and having circularly polarized wave excitation. 2. The antenna according to claim 1, wherein a block-shaped conductor or a block-shaped dielectric having a dielectric constant different from that of a dielectric forming the transmission and reception antenna is separately arranged between the transmission and reception antennas. apparatus. 3. The antenna device according to claim 1, wherein a plurality of types of block-shaped dielectrics having different dielectric constants are periodically arranged separately at predetermined intervals between the transmitting and receiving antennas. 4. The antenna device according to claim 1, wherein instead of the common ground conductor forming the transmitting and receiving antennas, the transmitting and receiving antenna dedicated ground conductors are individually used without being connected to each other. 5. The antenna device according to claim 1, wherein slots are separately arranged in the ground conductor between the transmitting and receiving antennas. 6. The antenna device according to claim 5, wherein a resistance element is separately loaded in an array slot of the ground conductor between the transmitting and receiving antennas.