JPH10135734A - Shared antenna device and portable radio unit using the antenna device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To use a unified antenna to both satellite communication and terrestrial communication by adding a linear radiation element to the tip of a feeder pin which supplies a high frequency current to a microstrip planar antenna via a capacitive element. SOLUTION: An MSA (microstrip planar antenna) 1 functions as a circular polarized antenna by the 1st frequency when the parameters such as the relative dielectric constant, size, thickness, etc., of a dielectric substrate 1c, the size of a radiation element 1b, and the positions, etc., of a feeder pin 1a are properly designed. A linear radiation element 8 works as a grounded liner polarized antenna by the 2nd frequency via a helical antenna that is placed under a ground conductor 4. A capacitive element 7 is connected to the upper end part of the pin 1a of the MSA 1, and the element 8 of the helical antenna, etc., is connected to the upper part of the element 7. The mutual interference is reduced between the 1st and 2nd frequencies via the element 7 and the radiation pattern of the circular polarized wave is particularly improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to the field of communications,
In particular, the present invention relates to an antenna device for portable wireless communication using a satellite and portable wireless communication performed via a wireless base station installed on the ground, and a portable wireless device using the same.

[0002]

2. Description of the Related Art In recent years, various companies have proposed a concept of a mobile phone using a satellite, and the frequency band is 1.6 GHz from a terrestrial mobile phone to a satellite, and from a satellite to a terrestrial mobile phone. Is assigned to the 2.4 GHz band. In the 1.6 GHz band, it is also assigned as a frequency band used for bidirectional communication from the ground to the satellite and from the satellite to the ground.
Furthermore, for terrestrial communication, 800 MHz band, 1.5
GHz band, 1.9 GHz band and the like are allocated.

[0003]

SUMMARY OF THE INVENTION The present invention provides an antenna which can be used for both satellite communication and terrestrial communication, and realizes a portable radio (portable telephone) which can communicate with both satellite and terrestrial communication using the antenna. That is the task.

[0004]

According to the present invention, a linear radiating element is added to the tip of a feed pin for supplying a high-frequency current to a microstrip planar antenna via a capacitive element. Thus, an integrated antenna without mechanical operation is used for both satellite communication and terrestrial communication.

[0005] According to the invention, the above-mentioned object is achieved by the means as set forth in the appended claims. The common antenna according to the present invention includes a microstrip planar antenna 1 (hereinafter abbreviated as MSA), a capacitive element 7 and a linear radiating element 8.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a schematic view of the structure of the present invention, in which the same parts are denoted by the same reference numerals, 1 is a microstrip planar antenna (MSA), 1a is a feeding pin, and 1b is a patch-shaped antenna. Radiating element, 1c is a dielectric substrate, 4
Is a ground conductor (conductor plate), 7 is a capacitive element, and 8 is a linear radiating element.

[0007] MSA1 is the relative permittivity of the dielectric substrate 1c.
Parameters such as dimensions and thickness of the dielectric, dielectric substrate 1
By appropriately designing the dimensions of the patch-shaped radiating element 1b to be attached to c, the position of the feed pin 1a, and the like, the antenna operates as a circularly polarized antenna at the first frequency. Further, as shown in FIG. 2, the helical antenna arranged below the ground conductor 4
The linear radiating element 8 operates at the second frequency as a quarter-wavelength grounded linearly polarized antenna.

The case where the MSA 1 operates as a circularly polarized antenna will be described. For example, a patch-shaped radiating element 1b is attached to the dielectric substrate 1c, and a one-point back-feed type MS is provided.
A1. At this time, if the long side and the short side are A and B, respectively, 100 × A / B = 102 to 103%
It is constituted so that it may be. At this time, on the longer side A, resonance occurs at a relatively low frequency, and elliptical polarization characteristics are exhibited.
The shorter side B resonates at a relatively high frequency, exhibits elliptical polarization characteristics orthogonal to the elliptical polarization, and operates as a circularly polarized antenna at frequencies between them. Further, in order to connect the power supply line 6 to the power supply pin 1a, the position of the power supply pin 1a is adjusted to achieve impedance matching. That is, the power supply pin 1a is placed on the diagonal of the square at 100 × (AB) /
What is necessary is just to arrange so that A = about 30%.

Next, the coupling between the MSA 1 and the linear radiating element 8 will be described. A capacitive element 7 such as a capacitor is connected to the upper end of the power supply pin 1a of the MSA 1, and a linear radiating element 8 such as a helical antenna is connected above the capacitive element 7. Through the capacitive element 7, mutual interference is reduced at the first frequency operating with circular polarization and the second frequency operating with linear polarization. In particular, the radiation pattern of circularly polarized waves is good.

FIG. 2 shows an example in which the composite antenna (Japanese Patent Application No. 8-19638) of the present applicant is combined with the shared antenna of FIG. 1 to form a composite antenna 12. The helical antenna 2 disposed below the MSA 1 is an MSA 1 Earth conductor 4
2 shows a structure in which the linear radiating element 2b is electrically connected and supplied with power. The helical antenna 2 of the present example is a 4-wire helical antenna as a representative example. 2, the same parts as those in FIG. 1 are indicated by the same reference numerals. Reference numeral 2a denotes a dielectric column (dielectric supporting column) around which the linear radiating element 2b is wound. Reference numeral 2c denotes an insulator interposed between the linear radiating elements 2b at the lower end of the helical antenna 2 so as to intersect in a non-contact manner. Reference numeral 2d denotes an intersection of the insulators 2c where the linear radiating elements 2b intersect in a non-contact manner. The symbol 3 is MSA
1 and a common feeding point of the helical antenna 2. The power supply pin 1a penetrates through the dielectric substrate 1c and is connected to a power supply line (coaxial line) 6 without contact with a hole provided in the ground conductor 4. The feed line 6 electrically connects the linear antenna 8 upward through the capacitive element 7.

FIG. 3 shows an example in which the composite antenna 12 of FIG. FIG. 4 shows a radiation pattern measured in the longitudinal section of the composite antenna 12 in the 1.6 GHz band and the 800 MHz band using the same configuration as that of FIG. Is an 800 MHz band, and the pattern mainly radiated upward is a 1.6 GHz band. 3, the same parts as those in FIG. 2 are denoted by the same reference numerals. Composite antenna 1
Numeral 2 is comprised so that it is included in the antenna holding cylinder 13 and rotates about the rotation axis A, so that the composite antenna 12 can be folded toward the housing of the portable wireless device 11 when waiting for an incoming call. Also, a microstrip planar antenna (MSA) 30 is built in the upper surface of the housing of the portable wireless device 11, and a diversity antenna is configured in combination with the composite antenna 12. The MSA 30 mainly provides the same zenith (9) as that of the composite antenna 12 in the right-handed (or left-handed) circular polarization mode.
0 °) direction. The diversity configuration includes the composite antenna 12, the MSA 30, and the radio unit 31 shown in FIG.
And a signal combining means (or signal selecting means) 32 of the composite antenna 12 and the MSA 30. Further, in FIG. 3, the composite antenna 12 is held by the antenna holding cylinder 13 and located above the communication unit 13a from the housing of the portable wireless device 11, and the gain loss in the low elevation angle direction due to the head of the human body during a call. It is devised to prevent. When making a call, the composite antenna 12 is set up as shown in FIG. 3, and communication is performed using a predetermined right-handed (or left-handed) circularly polarized wave. Then, during standby, the composite antenna 12 is rotated to a position where the composite antenna 12 is in close contact with the side surface of the housing of the portable wireless device 11. The composite connector 12 is rotated with respect to the housing of the portable wireless device 11 by the rotating connector 33. The dotted line in FIG. 5 shows a state where the composite antenna 12 is folded by this rotation. In this folded state, the direction of the composite antenna 12 is opposite to the direction in use and the turning direction of the circularly polarized wave is reversed, so that the sensitivity of the composite antenna 12 is significantly deteriorated. Therefore, during standby, the MSA 30 mainly functions.

[0012]

As described above, according to the present invention, by adding a linear radiating element via a capacitive element to the tip of a feed pin for supplying a high-frequency current to a microstrip planar antenna, mechanically Without switching operation,
It is possible to support a plurality of wireless communication services.
In addition, since mechanical switching is not performed, the reliability of the antenna unit and the wireless device main body is improved.

[Brief description of the drawings]

FIG. 1 is a diagram showing an embodiment of the present invention.

FIG. 2 is a diagram in which a helical antenna is connected below the embodiment of FIG. 1 to form a composite antenna.

FIG. 3 is a diagram illustrating an example in which the antenna of FIG. 2 is formed in a cylindrical shape and used in a portable wireless device.

FIG. 4 is a diagram showing radiation patterns of the antenna of FIG. 3 measured at a satellite communication frequency and a terrestrial mobile phone frequency band.

FIG. 5 is an antenna circuit block diagram of the portable wireless device of FIG. 3;

[Explanation of symbols]

 1: Microstrip planar antenna (MSA) 1a: Feeding pin 1b: Patch-like radiating element 1c: Dielectric 2a: Helical antenna 2a: Dielectric column (dielectric supporting column) 2b: Linear radiating element 2c: Insulator 2d: Intersection 3: Feeding point 4: Ground conductor (conductor plate) 6: Feeding line (coaxial line) 7: Capacitive element 8: Linear radiating element 11: Portable radio (cellular phone) 11a: Receiver 11b: Display unit 11c: Operation unit 11d: Transmission unit 12: Composite antenna 13: Antenna holding cylinder 13a: Communication unit 30: Microstrip planar antenna (MSA) 33: Rotating connector

Continued on the front page (51) Int.Cl. ⁶ Identification code FI H01Q 21/24 H01Q 21/24 H04B 1/38 H04B 1/38

Claims (4)

[Claims] 1. A back-fed microstrip planar antenna having a patch-shaped conductor on one surface of a plate-shaped dielectric and a ground conductor plate and at least one feeding pin on the other surface, A shared antenna device wherein a linear radiating element is electrically coupled to a top end via a capacitive element, and a portable wireless device using the same. 2. The shared antenna device according to claim 1, wherein said microstrip planar antenna is a circularly polarized antenna, and said linear antenna is a linearly polarized antenna, and a portable wireless device using said antenna. . 3. A common antenna device according to claim 1, wherein a helical antenna is electrically connected below a ground conductor of the microstrip planar antenna constituting the common antenna. Portable radio. 4. A shared antenna device according to claim 1, wherein said microstrip planar antenna and said linear antenna have operating frequencies different from each other at a first frequency and a second frequency, respectively. Portable radio.