JP3107150B2 - Crossed finger print antenna - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cross-finger print antenna, which is used for space diversity in a wireless communication system and includes two closely arranged print antennas.

[0002]

2. Description of the Related Art Several methods have been proposed to implement spatial diversity used in wireless systems.

FIG. 9 shows a conventional example of two dipole antennas arranged at a distance (Mobile antenna).
na systems handbook, Fuji
moto & James Arttech House
e, 1994, 141-143). This is performed via the connector 32 via the first input / output unit 31 of the communication system.
The first dipole antenna 30 is connected to the first dipole antenna. Further, a second dipole antenna 33 is connected to a second input / output unit 34 of the communication system via a connector 35. The distance D between these dipole antennas
11 indirectly defines the space diversity efficiency.

FIG. 10 shows the structure of another conventional printed antenna disclosed in the above document. The patch antenna 38 is supplied with power by the microstrip line 37. Further, another patch antenna 40 is fed by another microstrip line 39. The patch antenna 38 and the patch antenna 40 are separated by an interval D12, and the space D12 defines the space diversity.

[0005]

One of the problems in the conventional example shown in FIG. 9 is that it is impossible to use a dipole antenna if the area where diversity can be used is a narrow plane area. It is mentioned. That is, since this structure is based on a dipole, it cannot be used for a planar structure.

On the other hand, in the conventional example shown in FIG. 10, in order to use two patch antennas without deteriorating the patch efficiency, it is necessary to separate the patches by an interval corresponding to a minimum allowable interval for space diversity. Therefore, if the required spatial diversity is less than this minimum allowed interval,
It becomes impossible to use a patch structure. In other words, in a communication system, when it is required to reduce the interval between antennas in order to solve a problem in propagation, no measure has been proposed for using a patch structure antenna.

An object of the present invention is to provide a small planar space diversity antenna using a patch antenna for personal communication, which overcomes the drawbacks of the conventional method.

[0008]

According to the present invention, there is provided on a substrate,
The first feed line 1 having a width W1 formed on the substrate is formed on the substrate.
And is connected to the first patch 3 having a resonance length L2 resonating at the frequency F1 and having a non-resonance width W2. One resonance edge 6 of the first patch has a length L3 and a width W3. A plurality of finger-shaped portions 7 made of metal square pieces are arranged and connected at intervals D1 to define the inter-finger distance IFS, and the number of the finger-shaped portions is the resonance length L2 and the finger length. Width W
3 and a width W formed on the substrate so as to be parallel to the first feeder line and determined by the distance D1.
4 formed on the substrate by the second feed line 12
To feed the second patch 14 having a resonance length L22 resonating at the frequency F2 and a non-resonant edge width W5,
A plurality of metal square pieces each having a length L4 and a width W6 are connected to the finger-side resonance edge, respectively. Each finger of the first patch has a resonance edge. Are arranged between the fingers of the second patch at intervals DS1 in the extending direction of the second patch and at intervals DS2 in the extending direction of the non-resonant edge. By optimizing the width and length of each finger of the two patches as well as the spacing between each patch, a cross-finger print antenna is provided for optimal matching.

The resonance frequency can be made equal by making the resonance length L2 of the first patch equal to the resonance length L22 of the second patch.

According to the present invention, the first feed line 27
And a first patch 26 having a plurality of metal rectangular pieces arranged and connected to the resonance edges on both sides, respectively, and a second patch 26 arranged in parallel with the first power supply line. And a finger-like portion formed by a plurality of metal square pieces inserted between a plurality of finger-like portions at one of the resonance edges of the first patch. Are supplied by a second patch 24 arranged and connected to each other, and a third feed line 29 arranged in parallel with the first feed line, and one resonance edge portion is provided with the other of the first patch. A third patch 28 in which a plurality of metal square pieces inserted and arranged between the plurality of fingers at the resonance edge are arranged and connected with fingers.
And the first to third power supply lines and the first to third power supply lines.
It is noted that each patch is formed on the same substrate.
An interdigitated printed antenna is provided.

[0011]

The resonance frequency for a rectangular patch is determined by the length of the resonance edge at the desired frequency. that time,
The feed system provides a matching circuit for matching the input port to free space via the radiating structure. By changing the length of the non-resonant edge, the patch itself can be adjusted to change its input impedance. However, the radiation efficiency will be higher if there is more ease to match on the actual substrate and a minimum non-resonant length D1 is ensured. Therefore, if space diversity is used at a distance shorter than D1, the two patches as described above cannot be used because they overlap each other. Therefore, a complementary structure in which some fingers are provided in a part of the patch is configured.
Each patch is matched by the feed line structure and the inclusion of the fingers of the other patch.

[0012]

Embodiments of the present invention will be described with reference to the drawings. With reference to FIG. 1, in the first embodiment, the first feeder line 1 having a width W1 of 1 mm has a resonance length L
2 is connected to the first patch 3 having a width of 29.5 mm and a non-resonant width W2 of 18.67 mm. Five metal square pieces 7 having a length L3 of 10 mm and a width W3 of 2.5 mm are connected to one edge 6 on the resonance side of the first patch 3 so as to form a finger. These fingers are 3.5 mm
, And an inter-finger distance IFS of 6 mm is defined.

A second power supply line 12 having a width W4 of 1 mm and arranged in parallel with the first power supply line 1 has a resonance length L.
22 is 42.4 mm and the width W5 of the non-resonant edge is 34.8 m
m of the second patch 14. The length L4 is 1 at the resonance edge of the second patch 14 closer to the finger.
Four metal square pieces 16 having a width W6 of 2.5 mm and a width of 0 mm
Are connected to form a finger. Each of these fingers has a distance DS in the direction in which the resonance edge extends.
1 are 0.5 mm and the distance DS2 is 0.99 mm in the extending direction of the non-resonant edge, and are arranged alternately.

The last finger 77 of the first patch 3 is determined by the length L2 and the width of the other fingers, and is 5.5 mm.
With a width of The last finger of the second patch 14, like the others, is 10 mm long and about 12.4 mm high.

This structure has a thickness of 62 mils (1.6 mm).
And realized on a substrate having a dielectric constant of 3.38.

Referring to FIG. 2, the first patch 3 is:
A gain of 3 dB is achieved at 2.2 GHz.

FIG. 3 shows the second resonance frequency of 1.64 GHz.
Indicates that a gain of 4 dB was obtained.

Referring to FIG. 4, the gain with respect to the elevation angle at 2.2 GHz at a constant azimuth (azimuth) angle is shown, and the behavior is similar to that of the conventional patch.

Referring to FIG. 5, in the second embodiment,
A first feed line 1 having a width W1 of 1 mm is connected to a first patch 3 having a resonance length L2 of 29.5 mm and a non-resonance width W2 of 18.67 mm. One edge 6 on the resonance side of the first patch 3 has a length L3 of 10 mm and a width W3 of 2.
Five metal square pieces 7 of 5 mm are connected to form a finger. This finger has a distance D of 3.5 mm.
1 and defines an inter-finger distance IFS of 6 mm. A second feed line 12 having a width W4 of 1 mm and a resonance length L22 of 29.5 mm and a non-resonant edge width W5 of 18.8 mm is provided by a second feed line 12 arranged in parallel with the first feed line 1. Power is supplied to the patch 14. The length L4 is 1 at the resonance edge of the second patch 14 closer to the finger.
Four metal square pieces 16 having a width W6 of 2.5 mm and a width of 0 mm
Are connected to form a finger. Each of these fingers has a distance DS1 in the direction in which the resonance edge extends.
Is 0.5 mm, and the distance D in the extension direction of the non-resonant edge is
S2 is inserted alternately at an interval of 0.99 mm.

This structure has a thickness of 62 mils (1.6 mm).
And realized on a substrate having a dielectric constant of 3.38.

FIG. 6 shows a gain of better than 3 dB for each input and better than 10 dB for both inputs, 2.4.
4 shows matching performance in a frequency range of 4 GHz.

FIG. 7 shows a radiation pattern having a structure similar to that of a conventional patch.

Referring to FIG. 8, a third embodiment of the present invention will be described. The cross-finger-shaped printed antenna according to the third embodiment is fed by the first feeder line 27, and finger-shaped parts made of a plurality of metal square pieces are respectively arranged and connected to the resonance edges on both sides. The power is supplied by the first patch 26 and the second power supply line 25 arranged in parallel with the first power supply line 27, and one of the resonance edges has a plurality of power at one of the resonance edges of the first patch 26. A second patch 24 in which fingers are arranged and connected by a plurality of metal square pieces inserted and disposed between the fingers.
Power is supplied by a third power supply line 29 arranged in parallel with the first power supply line 27, and one resonance edge is provided between a plurality of fingers at the other resonance edge of the first patch 26. The third patch 28 is provided with finger-like portions each formed of a plurality of metal square pieces inserted and arranged. The dimensions and spacing of the fingers of each patch are the same as those of the antenna shown in FIG. 1 or FIG. Of course, the number of patches may be three or more.

[0024]

According to the present invention, it is possible to provide a small planar space diversity antenna using a patch antenna, which is suitable for personal communication.

[Brief description of the drawings]

FIG. 1 is a diagram showing a structure of an antenna according to a first embodiment of the present invention.

FIG. 2 is a diagram showing matching performance at a first frequency of the structure of FIG. 1;

FIG. 3 is a diagram showing matching performance at a second frequency of the structure of FIG. 1;

FIG. 4 shows a radiation pattern of the structure of FIG. 1;

FIG. 5 is a diagram showing a structure of an antenna according to a second embodiment of the present invention.

FIG. 6 is a diagram illustrating matching and gain performance of the structure of FIG. 5;

7 shows a radiation pattern of the structure of FIG.

FIG. 8 is a diagram showing a structure of an antenna according to a third embodiment of the present invention.

FIG. 9 is a diagram showing a conventional dipole diversity structure.

FIG. 10 is a diagram showing a conventional patch diversity structure.

[Explanation of symbols]

 1,27 First feed line 3,26 First patch 7,16,77 Finger portion 12,25 Second feed line 14,24 Second patch 28 Third patch 29 Third feed line 30 First dipole antenna 31, 34 Input / output unit 32, 35 Connector 33 Second dipole antenna

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-10-98329 (JP, A) JP-A-4-129302 (JP, A) JP-A-5-75329 (JP, A) 135007 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01Q 21/08 H01Q 1/38 H01Q 13/08

Claims (3)

(57) [Claims] 1. A first feed line 1 having a width W1 formed on a substrate and a first patch 3 having a resonance length L2 and a non-resonance width W2 formed on the substrate and resonating at a frequency F1. Connected to one of the resonance edges 6 of the first patch, a plurality of metal square pieces 7 each having a length L3 and a width W3 are arranged and connected at an interval D1, respectively. stipulates between distance IFS, the number of the fingers, the a resonant length L2, and the width W3, is determined by said distance D1, the in parallel to the first feed line Shape on board
The second feed line 12 formed by the width W4, the substrate
The second patch 14 formed on the second patch 14 and having a resonance length L22 resonating at the frequency F2 and having a non-resonant edge width W5 is fed to the finger-side resonance edge having a length L4. The fingers 16 of a plurality of metal square pieces having a width W6 are connected to each other, and each finger of the first patch has a distance DS1 in the direction in which the resonance edge extends, and In the extending direction, they are inserted and arranged between the fingers of the second patch at intervals DS2, respectively, and the width and length of each finger of the first and second patches and each A cross-finger print antenna that obtains optimum matching by optimizing the interval between patches. 2. The resonance length L2 of the first patch is equal to the resonance length L22 of the second patch, so that the resonance frequency is the same. Crossed finger print antenna. 3. A first patch 26, which is fed by a first feed line 27 and has a plurality of metal rectangular small fingers arranged and connected to the resonance edges on both sides, respectively.
Power is supplied by a second power supply line 25 disposed in parallel with the first power supply line, and one of the resonance edges has a plurality of finger-like portions at one of the resonance edges of the first patch. Power is supplied by a second patch 24 in which finger portions of a plurality of metal square pieces inserted and disposed between the second patch 24 and a third power supply line 29 arranged in parallel with the first power supply line. A finger having a plurality of metal square pieces inserted and arranged between a plurality of fingers at the other resonance edge of the first patch is connected to one of the resonance edges. look including a third patch 28, wherein the first through the third feed line first to third pad
The switches are formed on the same substrate.
Interdigital printed antenna to be.