JP2009188890A - Antenna device and mobile wireless device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a reverse F type antenna device which is thin and of high performance. <P>SOLUTION: The antenna device includes: a conductive plate-shaped element 101; a power supply part 102 of the plate-shaped element 101; a short circuit part 105 of the plate-shaped element 101; a ground plane 106 arranged practically parallel to the plate-shaped element 101; a power supply line 103 arranged practically vertical to the plate-shaped element 101 and electrically connecting the plate-shaped element 101 and the power supply part 102; and a short circuit line 105 arranged practically vertical to the plate-shaped element 101 and electrically connecting the plate-shaped element 101 and the short circuit part 104. The power supply line 103 and the short circuit line 105 are arranged at a predetermined interval, and the power supply line 103 or the short circuit line 105 is arranged so that it is not connected between the ground plane 106 and the plate-shaped element 101 at the shortest interval but detours on the plane practically vertical to the plate-shaped element 101. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a plate antenna having high antenna performance.

  In recent years, mobile phones have become widespread, and antennas have been built and lowered in height for thinning, miniaturization, and design diversity. In addition, the protrusion of the antenna impairs the appearance of the portable wireless device, and in recent years, the antenna has been built in.

Here, in a cellular phone with a built-in antenna, there is an inverted F antenna or the like as means for obtaining good antenna performance (for example, Patent Documents 1 and 2).
JP-A-4-157908 JP 2003-92510 A

  However, when constructing an inverted-F antenna, it is necessary to take the height of the plate-shaped antenna element and the substrate in order to ensure the characteristics, and if the height is not sufficient, the plate-shaped antenna It was necessary to increase the area of the element. Therefore, it has been an obstacle to miniaturization and thinning of portable wireless devices.

  The present invention has been made to solve the conventional problems, and is a low-profile inverted-F antenna that does not require a large space, secures a wide band, and exhibits high antenna performance. It is an object of the present invention to provide a small and thin portable wireless device including the device and the antenna device.

  In order to solve the above-described problem, the antenna device of the present invention includes a portable wireless device of the present invention that includes a conductive plate-like element, a feeding portion of the plate-like element, a short-circuit portion of the plate-like element, A ground plane disposed substantially parallel to the plate-shaped element; a power supply line disposed substantially perpendicular to the plate-shaped element to electrically connect the plate-shaped element and the power feeding portion; and substantially to the plate-shaped element. A short circuit line that is arranged vertically and electrically connects the plate-like element and the power supply unit, and the power supply line and the short circuit line are disposed at a predetermined distance, and the power supply line or The short-circuit line is configured so as to be detoured on a plane substantially perpendicular to the plate-like element without being connected at the shortest between the ground plane and the plate-like element.

  With the above configuration, the resonance frequency can be easily adjusted by the length of the detouring line, and the antenna can be thinned by the detouring line.

  When the bypass portion is directly connected to the antenna top surface without adopting the above configuration, only resonance due to the path connecting the short-circuit point and the antenna top surface in the shortest occurs. At this time, the antenna resonance becomes higher than that of the present invention, and it is necessary to increase the size in order to obtain a low band. Moreover, since the short-circuit line length is the fundamental frequency, the resonance width is narrower than that of the present invention. Therefore, the present invention is useful for an antenna that needs to cover a wide band.

  According to the present invention, a thin and high-performance antenna device can be provided, and further, a thin and high-performance portable wireless device can be provided.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 shows an antenna device 100 according to an embodiment of the present invention. FIG. 2 shows a portable radio 200 equipped with the antenna device 100 of the present invention.

  The antenna device 100 includes a plate-like element 101 on a sheet metal, a feeder unit 102 that supplies current to the plate-like element 101, a feeder line 103 that electrically connects the plate-like element 101 and the feeder unit 102, and a plate-like element. 101 is composed of a short-circuit portion 104 serving as a ground, a short-circuit wire 105 for electrically connecting the plate-like element 101 and the short-circuit portion 104, and a ground plane 106 that is a circuit board including the power feeding portion 102 and the short-circuit portion 104. The

  When the antenna device 100 is mounted on the portable wireless device 200, the antenna device 100 is mounted so as to fit inside the housing 201 that forms the appearance of the portable wireless device 200 as shown in FIG.

  The plate-like element 101 is installed substantially parallel to the ground plate 106. By being installed in parallel, it operates as a ground plane of an inverted F antenna.

  The short-circuit line 105 of the antenna device 100 of the present invention is detoured so as not to be substantially linear between the plate-like element 101 and the ground plane 106 (short-circuit line detour 105a). By providing the short-circuit line 105a with the short-circuit line 105a, the plate-like element 101 and the short-circuit line detour 105a can be capacitively coupled. Therefore, an antenna resonance path other than the short-circuit line is generated, and the resonance band is increased. Expanding. Furthermore, by adjusting the length of the short circuit bypass, the antenna device 100 can be easily operated at a desired resonance frequency. Therefore, the resonance frequency band unique to the antenna can be widened.

  Here, when the capacitive coupling is not performed between the plate-shaped element 101 and the short-circuit line detour 105a, that is, when there is no gap between the plate-shaped element 101 and the short-circuit line detour 105a, the above effect cannot be obtained. . This is because the antenna resonance is a resonance that excites only in the shortest path from the short-circuit line to the antenna top surface.

  As described above, the distance between the plate-like element 101 and the ground plane 106 can be reduced by providing the short-circuit line detour 105a, so that the antenna device 100 can be shortened and the short-circuit line detour 105a can provide a resonance frequency unique to the antenna. The bandwidth can be increased. Furthermore, since the area of the top surface of the plate-like element 101 can be widely used, it is possible to suppress a reduction in radiation efficiency due to a decrease in antenna radiation volume.

  In the antenna device 100 of the present invention, the short-circuit line 105a is provided in the short-circuit line 105, but the same effect can be obtained even if the detour is provided in the feeder line 103. Further, a detour may be provided on both the feeder line 103 and the short-circuit line 105.

  The antenna device of the present invention can be diverted to, for example, a mobile phone, PHS, game machine, electronic dictionary, notebook computer, PDA, and the like.

External view of antenna device of the present invention External view of a portable radio equipped with the antenna device of the present invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Antenna apparatus 101 Plate-shaped element 102 Feeding part 103 Feeding line 104 Short circuit part 105 Short circuit line 106 Ground plate 200 Portable wireless device 201 Case

Claims (3)

A conductive plate-like element;
A feeding portion of the plate-like element;
A short-circuit portion of the plate-like element;
A ground plane disposed substantially parallel to the plate-like element;
A feed line that is arranged substantially perpendicular to the plate-like element and electrically connects the plate-like element and the feed portion;
A short-circuit wire that is disposed substantially perpendicular to the plate-like element and electrically connects the plate-like element and the short-circuit portion,
The feeder line and the short-circuit line are arranged at a predetermined distance,
The feeder line or the short-circuit line is disposed so as to bypass the plane element and a substantially perpendicular plane without being connected in the shortest between the ground plane and the plate element.
Antenna device. Both the feeder line and the short-circuit line are arranged so as to bypass on the plane substantially perpendicular to the plate-like element without being connected at the shortest between the ground plane and the plate-like element,
The antenna device according to claim 1. A portable wireless device comprising the antenna device according to claim 1.

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