JPH1013365A - Antenna breakage detection device - Google Patents

Abstract

(57) [Problem] To provide an antenna damage detection device which has a high detection accuracy, does not require adjustment, can be configured simply and at low cost. A photocoupler is provided, a direct current loop through which a direct current flows through a photodiode of the photocoupler and an antenna is formed, and a breakage of the antenna is detected by monitoring an output of the photocoupler.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a technique for automatically detecting antenna breakage of a wireless device.

[0002]

2. Description of the Related Art A conventional radio device utilizes the fact that when an antenna is damaged, the input VSWR of the antenna deteriorates.
The level of the reflected wave from the antenna was detected, and the comparator was compared with a normal value to detect breakage of the antenna. FIG.
FIGS. 2A and 2B are main block diagrams of a wireless device for explaining a conventional antenna damage detection method. FIG. 2A shows a detector 1 that detects a reflected wave from the antenna 12 through a coupler 13 provided between the main signal line 11 and the antenna 12.
The DC level output from the detector 14 is compared with a normal level in the comparator 15 and detected.
FIG. 2B shows an example of a wireless device using the circulator 16.
As in (a), breakage of the antenna is detected.

[0003]

However, since the breakage of the antenna is detected at the level of the reflected wave, the detection accuracy deteriorates due to fluctuations in the output level of the detector due to temperature fluctuations, changes in the loss between the antenna and the detector, and the like. was there. Further, in addition to the necessity of adjusting the circuit due to the variation of the VSWR of the antenna itself, the circuit becomes complicated and the cost increases.

An object of the present invention is to provide an antenna breakage detecting device which has a high detection accuracy, does not require adjustment, and can be constructed simply and at low cost.

[0005]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides an antenna without an additional circuit.
DC current is passed from the device side to the antenna through the photocoupler, and the output of the photocoupler turns ON / OF the DC current.
Monitor F.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS PH using helical antenna
In the base station for S, in order to detect the deterioration of the communication quality due to the antenna breakage at an early stage, a DC current flows from the device side to the antenna unit without using an additional circuit in the antenna unit, and a monitor circuit using a photocoupler is used. By monitoring ON / OFF of the DC current, the antenna has a function of detecting antenna breakage that is stable against temperature fluctuations and the like, and the configuration of the monitor circuit is simple and the price is low.

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram of a main part of a PHS base station apparatus according to an embodiment of the present invention. In addition to a main signal line 1 block for transmitting and / or receiving a radio signal, an antenna breakage detection is provided on the apparatus side. Blocks are provided. A helical antenna is used as the antenna 2, and a main signal line 1 on the device side and a DC power
Respectively. DC power supply 3 is a current limiting resistor 4,
By connecting the photodiodes of the photocoupler 5 in series,
The four signal lines 6 are connected to the main signal line 1 to apply a direct current to the antenna conductor. When the antenna 2 is normal, a direct current flows, so that the photocoupler 5 operates to obtain an output from the output terminal. When the antenna is damaged, the antenna conductor is cut off, so that the photocoupler 5 does not operate and the output is cut off. The output end of the photocoupler 5 is connected to a monitor circuit (not shown), and when the photocoupler 5 is not operated, the monitor circuit detects breakage of the antenna.

[0008]

The antenna damage detecting device of the present invention has the following advantages.

The circuit configuration is simple.

It is inexpensive.

[0011] The mounting area of the circuit components on the substrate is small,
The substrate does not increase in size.

The operation is very stable because it is not affected by temperature fluctuations and the like.

There is no need for adjustment.

[Brief description of the drawings]

FIG. 1 is a main block diagram of a PHS base station apparatus according to an embodiment of the present invention.

FIGS. 2A and 2B are main block diagrams of a wireless device for explaining a conventional antenna damage detection method.

[Explanation of symbols]

 1: Main signal line 2: Antenna 3: DC power supply 4: Current limiting resistor 5: Photocoupler 6: λ / 4 line 11: Main signal line 12: Antenna 13: Coupler 14: Detector 15: Comparison circuit 16: Circulator

Claims (1)

[Claims] 1. A photocoupler is provided, a direct current loop through which a direct current flows through a photodiode of the photocoupler and an antenna is formed, and a breakage of the antenna is detected by monitoring an output of the photocoupler. Characteristic antenna damage detection device.