JP2006019840A - Position detecting system and its wireless machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a system for detecting the position of a mobile wireless machine precisely without sacrifice of convenience. <P>SOLUTION: Position is detected using an automatic answering mobile wireless unit comprising a receiving circuit, a transmitting circuit, an antenna, a clock signal generating means, a counter and a variable attenuator and transmitting an automatic answering radio wave upon receiving a predetermined radio wave and then reducing its transmission power gradually to stop the radio wave, a plurality of detection wireless machines provided at different locations in order to transmit a predetermined signal under direction of a control means and to notify a radio wave received by the mobile wireless machine to the control means, and the control means for transmitting a predetermined signal to each detection wireless machine, specifying one detection wireless machine performed reception till latest and determining that the mobile wireless machine exists in the vicinity of the specified detection wireless machine. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

The present invention relates to a system for detecting the position of a radio of a mobile station, and a radio used for the application.

In order to determine the position of the mobile station radio, there is a method in which detection radios are installed at a plurality of different locations in the area, radio waves emitted from the mobile station are received, and estimated from the received intensity. This method assumes that the mobile station radio is located near the specific detection radio that received radio waves with the strongest intensity from multiple detection radios. This method is simple, but its accuracy is not good. There are cases.
JP 2004-030530 A

One factor that degrades accuracy is saturation of the detection radio. That is, there may be a case where a plurality of detection wireless devices in the vicinity each show the maximum value and the position cannot be specified. Therefore, an object of the present invention is to solve the above-mentioned problems without impairing simplicity.

A reception circuit, transmission circuit, antenna, clock signal generation means, counter, and variable attenuator. When a predetermined radio wave is received, a response signal radio wave is generated and the transmission power is gradually reduced to stop the automatic response. Station radio,
A plurality of detection radios installed at different locations, each of which transmits a predetermined signal according to an instruction from the control means, and notifies a reception signal to the control means when receiving radio waves from the radio of the mobile station,
Each of the detection radios transmits a predetermined signal and one of the detection radios that has been notified of reception until the latest is specified, and the radio of the mobile station is located in the vicinity of the specified detection radio The position is detected by the control means that determines that the problem exists, and the problem is solved.

According to the present invention, since the determination is not performed based on the strength of the received radio wave intensity, the accuracy of position detection can be improved without being affected by the protracted problem.

FIG. 1 shows a radio of the present invention. The predetermined radio wave is sent to the receiving circuit via the antenna. The reception circuit performs tuning, detection, etc., and generates a trigger signal.

The trigger signal is applied to the transmission circuit and the clock signal generating means. When the transmission circuit receives the trigger signal, it adds a predetermined response signal to the variable attenuator.

The variable attenuator has attenuation amount setting means for determining an attenuation amount, and gives the attenuation amount set by the attenuation amount setting means to the response signal from the transmission circuit.

The attenuated response signal is amplified by the power stage and transmitted from the antenna. The power stage may be omitted depending on the required transmission power.

On the other hand, the clock signal generating means that receives the trigger signal generates a pulsed clock signal and adds it to the counter.

The counter counts clock pulses and supplies the count data to the attenuation amount setting means of the variable attenuator. In the present invention, the attenuation amount of the variable attenuator is increased every time a clock pulse is applied.

Next, when the count advances and reaches a predetermined value, the counter generates a reset signal. The reset signal is applied to the transmission circuit and the clock generation means to stop the respective operations.

The control means is connected to each of the detection radio devices and commands transmission of a predetermined signal. In addition, after the transmission command, a reception notification issued from each detection wireless device is received for a certain period of time, and the ID of the detection wireless device that made the reception notification is stored.

After the time-out, the ID of the detection radio that has made the last reception notification is displayed. If no reception notification is made, a predetermined process to be performed for the abnormal situation is performed as an abnormal situation.

Furthermore, it is more convenient to have map data and installation location data of the detection radio in advance and display an image for marking the detection position on the map.

... Radio device of the present invention ... Detection radio and control means of the present invention ... Flow chart of control means

Claims (2)

A radio that automatically responds when it receives a predetermined radio wave,
The radio comprises a receiving circuit, a transmitting circuit, an antenna, a clock signal generating means, a counter, and a variable attenuator.
When the receiving circuit receives a predetermined radio wave, it sends a received signal to the clock generating means,
The clock signal generating means generates a clock signal when receiving the received signal,
The counter counts the clock signal to create attenuation data and generates a reset signal when a predetermined number of clock signals are counted,
The variable attenuator sets an attenuation amount corresponding to the attenuation amount data, attenuates a transmission signal from the transmission circuit, and supplies the attenuated signal to an antenna. A radio of the mobile station according to claim 1,
A plurality of detection radios installed at different locations that transmit the predetermined signal in response to an instruction from the control means and notify the control means of the received signal when receiving radio waves from the radio of the mobile station; ,
Each of the detection radios is allowed to transmit the predetermined signal, and one of the detection radios that has been notified of reception is specified, and the movement to the vicinity of the specified detection radio is performed. A position detection system comprising the control means for determining that a station radio is present.