JPH0354414Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a communication antenna, and particularly to improvements in whip antennas used in portable radios, in-vehicle radios, and the like.

Conventionally known whip antennas include rod-shaped antenna elements, and antennas that increase gain by providing a phase converter (coil section, etc.) to stack rod-shaped radiating elements in multiple stages to increase gain. It is being

Figures 1a and 1b show an example of a conventional whip antenna, in which 1 is a top member, 2 is a radiating element,
3 is a cap nut, 4 is a coil cover, and 5 is a plug.

Inside the coil cover 4, coils 6 and 7 constituting a matching device are wound around a bobbin 8.

It is clear that in any antenna, in order to perform transmission and reception under optimal conditions, impedance matching must be achieved between the antenna element and the radio device or feeder line.

As this matching means, the feeding method using a coil shown in FIG. 1, the J-type feeding method, the power feeding method, and the like are known.

However, in either feeding method, it is necessary to adjust the built-in matching section for each antenna according to the feeding conditions, and even when using a whip antenna designed for high gain, the coil in the phase converter section must be adjusted. It was something that should not have happened. In other words, some matching devices or phase converters use coils, and some are wound around a bobbin or a coil holding insulator for matching, and others are phase converters. However, when the coils with this configuration are used at high frequencies in the VHF and UHF bands, the variations in each coil cannot be ignored, so each coil needs to be adjusted, which is difficult to work with, and also requires space and cost. There were also problems with this point.

However, regarding the matching part, there is a means as disclosed in Japanese Utility Model Publication No. 54-4912. This is a printed board version of the matching section based on the J-type power feeding method described above, and several adjustment points are provided on the printed board to facilitate adjustment.

However, even with such a proposal, the only problem that remains is that adjustment work is required.

Further, the matching coil of the conventional whip antenna has a three-dimensional shape, and each circular arc portion of the coil is successively arranged in series, so that radio wave radiation due to the current flowing therein is not completely canceled. Therefore, unnecessary radiation is generated, the intended radiation pattern cannot be obtained, and radiation efficiency and reproducibility are also impaired.

The present invention has been devised to solve all of the problems of the prior art, and provides a stable whip antenna without adjustment by making all the coil parts into printed circuit boards.

2a, b and c show the principle diagram before explaining the present invention.

In the drawings, reference numeral 9 denotes a printed circuit board installed upright within the cover 4, on which a coil portion 10 is formed.
The coils 6 and 7 shown in FIG. 1 correspond to those wound around the bobbin 8, and the coil portion 10 only needs to be formed to meet the power supply conditions at the time of design. Points etc. will be unnecessary.

3a, b and c show an embodiment according to the present invention, in which a printed circuit board is provided as a coil part of the phase converter in the same way as the matching part, and a coil part 11 is provided.
2 is formed. The coil section 12 of this phase converter may also be set at the time of design in the same way as the coil section 10.

As explained above, according to the present invention, the coil part as a matching filter and phase converter is formed using a printed circuit board in a whip antenna designed for high gain, so that the electrical characteristics are uniform,
This not only improves productivity and reliability, but also provides practical advantages in terms of space and cost.

In particular, compared to conventional coil-type whip antennas, the coil of the present invention is formed flat on a printed circuit board, so radio wave radiation due to the current flowing through it is almost completely canceled.
The generation of unnecessary radiation as in the past is drastically reduced. Therefore, an intended radiation pattern can be easily obtained, and a whip antenna with excellent radiation efficiency and reproducibility can be realized without adjustment.

As explained above, according to the present invention, a printed circuit board on which a coil part is formed is used as a matching box and a phase converter to increase the gain of the whip antenna, so that the electrical characteristics are made uniform and productivity is improved. This not only improves reliability, but also provides superior radiation efficiency and reproducibility compared to conventional coil-type whip antennas, and is also advantageous in terms of space and cost.

[Brief explanation of the drawing]

Figures 1a and b are diagrams each showing an example of a conventional whip antenna, Figures 2a, b, and c are diagrams of the principle before explaining the present invention, and Figures 3a, b, and c are diagrams of the present invention, respectively. It is a figure showing one example. DESCRIPTION OF SYMBOLS 1... Top member, 2... Radiating element, 3... Cap nut, 4... Cover, 5... Connector, 9, 11...
...Printed circuit board, 10, 12...Coil part.

Claims (1)

[Scope of utility model registration request] In a whip antenna equipped with a radiating element 2 and a matching box made up of a printed circuit board 9 connected to the radiating element 2 and housed in a cover 4, the printed board 9 is installed almost vertically in the cover 4, and the matching box is connected to the radiating element 2. A coil portion 10 is formed on the printed circuit board 9 in a planar shape to remove unnecessary radiation and meet predetermined power feeding conditions, and the radiating element 2 has a phase converter for measuring the high gain of the antenna. have,
A whip antenna characterized in that a coil portion 12 of the phase converter is formed in a planar shape on a printed circuit board 11 that is erected substantially vertically.