JP2009033431A - Mobile communication system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mobile communication system with an emergency call function capable of obtaining an emergency report without a switch operation by a party.
SOLUTION: Mobile stations A and B equipped with GPS transmit the position of the mobile station detected by GPS to the base station, and the base station no longer changes over a predetermined determination time. When the mobile station is abnormal, a warning is displayed.
Thus, the mobile stations A and B can be configured to notify the base station of the occurrence of an abnormality without operating an emergency switch or the like.
[Selection] Figure 1

Description

  The present invention relates to a wireless communication system including a base station and a mobile station, and more particularly to a mobile communication system having an emergency call function.

  For example, in corporate taxis, etc., from the viewpoint of operational efficiency, each vehicle is equipped with a radio to make it a mobile station so that it can communicate arbitrarily between the command center and each mobile station or between mobile stations. Conventionally, however, a wireless system that can inform the center of an emergency state by operating an emergency switch is known (for example, see Patent Document 1). In this system, when an emergency situation occurs, an emergency transmission button is pressed by a party such as a taxi occupant, so that the occurrence of the emergency situation is reported to, for example, a base station.

FIG. 5 shows an example of a mobile communication system having such an emergency call function. As shown in the figure, each of the base station and the plurality of mobile stations A and B includes a radio T / R, and a communicable area. In this case, the base station serves as a command center, the mobile stations A and B are vehicles, where M is a microphone and S is a speaker.
Each of the mobile stations A and B is provided with an emergency call button EB, and an emergency signal is transmitted from the radio T when the emergency call button EB is pressed during operation. is there. Needless to say, the mobile station is not limited to two stations A and B.

Then, in the mobile radio system, an example of the radio T / R used in each of the mobile stations A and B will be described in detail with reference to FIG. 6. First, the radio T / R shown in FIG. R is roughly divided into a radio main unit 1 and a control unit 2. The radio main unit 1 is provided with a receiving unit 11 and a transmitting unit 12, which are switched between the receiving mode and the transmitting mode to operate. The radio main unit 1 is provided with a baseband processing unit 13, a frequency synthesizer 14, and an antenna duplexer 15, and an antenna 16, a transmitter 17, and a receiver 18 are provided outside. Here, the transmitter 17 is the microphone M in FIG. 3 and the receiver 18 is the speaker S.
On the other hand, the control unit 2 includes a CPU (Central Processing Unit) 21, ROM 22, RAM 23, and electrically erasable / writable RAM 24, and an operation unit 25, a display unit 26, and an emergency call button 27 are provided outside. Is provided.

In the reception mode, a signal received by the antenna 16 is input to the receiving unit 11 via the antenna duplexer 15. Then, after being amplified by the high frequency amplifier 111, the frequency is converted into an intermediate frequency signal by the reception local transmission signal input to the reception mixer 112 and supplied from the frequency synthesizer 14. Then, after being amplified by the intermediate frequency amplifier 113, it is demodulated into a baseband signal by the demodulator 114.
The demodulated baseband signal is supplied to the baseband processing unit 13, processed by the reception signal processing circuit 131, output to the receiver 18, and reproduced as sound. The output of the reception signal processing circuit 131 is supplied to the control unit 20 together with the reception data, and is then output to the display unit 26 so that a necessary display is given.

On the other hand, in the transmission mode, the audio signal output from the transmitter 17 is input to the transmission signal processing unit 132 of the baseband processing unit 13 together with the data output from the control unit 20, where predetermined processing is performed. Then, it is input to the transmission unit 12. Then, the signal is modulated by the modulator 123 and then input to the transmission mixer 122, where it is converted into a high frequency signal by the transmission local transmission signal supplied from the frequency synthesizer 14, and the power is amplified by the transmission power amplification unit 121. Is supplied to the antenna duplexer 15 and transmitted from the antenna 16.
Control necessary for the reception operation and transmission operation at this time is performed by the control unit 20.

For this reason, the control unit 20 is provided with a CPU 21 as shown in the figure, and programs and adjustment values necessary at this time are stored in the ROM 22 in advance. At this time, the RAM 23 is used as a work area. Here, the electrically erasable / writable RAM 24 is composed of, for example, a flash memory, and also functions to store and hold various parameters and tables necessary at this time. Here, the operation unit 25 is provided as a man-machine interface, and is used to operate the radio T / R, and the display unit 26 is used to display the operation state of the radio T / R.
At this time, the emergency call button 27 functions as an emergency call switch, and is pressed when an emergency occurs, and instructs the control unit 20 to perform an emergency operation.

For this reason, the CPU 21 is further provided with a program for control necessary for this emergency notification. When an emergency operation is instructed by this, after the operation of the radio main unit 1 is set to the transmission mode, The emergency call data prepared in advance is read from the RAM 23 and controlled so as to be transmitted from the antenna 16.
Therefore, according to this prior art, when an emergency situation occurs, for example, an operator of the mobile station can notify the base station of the occurrence of the emergency situation by simply pressing the emergency call button 27.

At this time, in recent years, the mobile station is usually equipped with a GPS (Global Positioning System) so that the position of each mobile station can be grasped. In this case, GPS-AVM ( It is called an “Automatic Vehicle Monitoring” system (see also Patent Document 1).
JP 2005-128908 A

The above prior art does not take into consideration the point that a switch operation is required for notification of an emergency situation, and there is a problem in executing an accurate and reliable notification. That is, in the case of a taxi or the like, an accident is the main emergency, and although the probability is low, a crime such as hijacking (car robbery) is also taken into consideration.
However, in these cases, it is difficult for a party such as a taxi occupant to operate the switch. Therefore, in the prior art, there is a problem in executing an accurate and reliable report.

  An object of the present invention is to provide a mobile communication system with an emergency call function that can obtain an emergency report without a switch operation by a party.

  The above object is to detect a position of a mobile station in a mobile communication system having a plurality of mobile stations and a base station, performing wireless communication with each other, and monitoring the abnormality of the mobile station by the base station. And position information transmitting means for transmitting position information to the base station, and arithmetic means for detecting a position change of the mobile station based on position information received from the mobile station in the base station, the base station, This is achieved by determining that the mobile station is abnormal when the position of the mobile station does not change for a predetermined determination time or more.

  Normally, if the position of the mobile station does not change for more than a certain period of time, it can be assumed that an accident or crime has been encountered, except in the case of a break or standby. Can be reported.

  The mobile communication system with an emergency call function according to the present invention will be described in detail below with reference to the illustrated embodiments. Here, FIG. 1 is an embodiment of a mobile communication system with an emergency call function according to the present invention. In the figure, each of a base station and a plurality of mobile stations A and B is equipped with a radio T / R, It is the same as in the prior art described in FIG. 5 that communication can be performed within the communicable area, in which the base station becomes the command center and the mobile stations A and B are mounted on the vehicle. However, in this embodiment of FIG. 1, each mobile station A, B is different in that it does not have an emergency call button EB, but instead is provided with a GPS. Therefore, in this embodiment, the mobile station A, As shown in FIG. 2, the radio T / R used for B includes a GPS 3. The remaining points are the same as those of the prior art described with reference to FIG. 6 as far as the hardware configuration is concerned, except that the contents of control by the CPU 21 are different. At this time, the GPS 3 may be a vehicle equipped with a normal car navigation system.

When the GPS 3 is in an operating state, it autonomously detects the positions of the mobile stations A and B, that is, the position of a vehicle such as a taxi sequentially in a relatively short period, and inputs the position information to the control unit 2. Work. Therefore, the CPU 21 of the control unit 2 sequentially captures this position information, supplies it to the transmission unit 12, transmits it from the antenna 16, and controls it to be received by the base station.
Therefore, the base station sequentially receives the transmitted position information, knows the position change of the mobile station that transmitted the position information by comparing the position information at the timing before and after, and determines that the position change is set in advance. When it does not occur over a period of time, it is determined that some abnormality has occurred in the mobile station.

For example, when a traffic accident occurs in a taxi or the like, the occurrence of an emergency situation is notified, but if the caller is injured at this time, the emergency switch may not be operated.
In addition, when a crime is being conducted, it is customary that the target person is extremely restricted in movement, so it is difficult to operate it with normal switches, etc. Emergency calls are difficult unless prepared.
Thus, in such an emergency situation, the vehicle is usually stopped. Therefore, according to this embodiment, even if the emergency switch is not operated, the vehicle is stopped and only a certain time has elapsed. Thus, the base station can determine that an abnormality has occurred in the mobile station, and as a result, an accurate report can be obtained with certainty.

By the way, when implementing the present invention, it is necessary to set an appropriate time as the above-described determination time. This is because, for example, the position does not change even when waiting for a signal or temporarily stopping.
In the case of a taxi, it is necessary to consider passengers getting on and off. In addition, the operation pattern may include the “rest time” and “waiting time” of the occupant.
Therefore, the operation at the mobile stations A and B is as shown in the flowchart of FIG. 3, for example, and the operation at the base station is as shown in the flowchart of FIG.

First, the processing of FIG. 3 will be described. This processing is started when the operation of the radio T / R is started up. At this time, since the above consideration is required, the taxi occupants equipped with the mobile stations A and B need to stop in advance when the situation “rest time” or “waiting time”. To input stop mode information to the control unit 2. Note that the information form at this time is either “with set” or “without set”.
If the process of FIG. 3 is started, it will wait for position information to be input from GPS3 first (S30). When new position information is input, first, the stop mode is taken in (S31), and then the radio T / R is set to transmit operation (S32). Thereafter, the new position information and mode information just received are transmitted. Input to the unit 12 (S33). Thereafter, the process returns to the first process (S30).

At this time, the GPS 3 sequentially performs position measurement with a period of about 20 seconds, for example. Therefore, new position information is input to the control unit 2 every about 20 seconds. Therefore, new position information and stop mode information are transmitted from the mobile stations A and B about every 20 seconds. Will be.
As a result, the base station receives new position information about every 20 seconds, and each time, either “with set” or “without set” is received as the stop mode information. become.
Then, next, the process in the base station shown in FIG. 4 is demonstrated. Here, the process of FIG. 4 is also started when the radio T / R of the base station is started up. First, reception of position information and stop mode information is awaited (S40). Next, it is checked whether or not the stop mode information is set (S41). If the result is YES, that is, “set”, the process returns to step S40.

On the other hand, if the result in step S41 is NO, that is, “no set”, the position information just received is stored in the memory as data M (S42). Next, the position information stored in the memory at the previous timing is read and used as data N (S43). Thereafter, it is checked whether data M and data N are equal (S44).
Here, first, it is assumed that the data M and the data N are not equal. Then, this means that the position of the mobile station A or the mobile station B has changed, that is, a taxi is traveling. Therefore, when the result in process S44 is NO, the counter is reset (S45), and the process returns to the first process (S40).
On the other hand, when the result of this process S44 is YES, the position of the mobile station A or the mobile station B does not change, and in this case, it means that the taxi is stopped. Therefore, this time, first, the counter is incremented (S46), and 1 is added to the count value C.

Next, the count value C is compared with a determination value D set in advance to a predetermined value, and it is checked whether or not C = D (S47).
First, when the result is NO, that is, when C <D, the process ends here, and the process returns to the initial process (S40).
On the other hand, if the result in step S46 is YES, that is, if C = D, it is set abnormally (S47), and it is assumed that an emergency has occurred in the mobile station (A or B) at this time. Is finished.
Here, when set abnormally, a center management device (not shown) in the base station performs an alarm operation and displays that an abnormality has occurred in the vehicle equipped with the mobile station.

Next, the meaning of “C = D” in step S46 will be described.
First, the count value C at this time is reset by the process S45 of FIG. 4 and incremented by the process S46. Accordingly, the count value C increases from 0 to 1 only when the process S46 is continuously executed, and the increase period is about 20 seconds as described above.
At this time, the process S46 is continuously executed when the position information does not change and continues as described above. Therefore, the count value C becomes 1 first. This is when about 20 seconds have elapsed since the time at which no longer changes.

Therefore, if 1 (D = 1) is set as the determination value D, about 20 seconds have elapsed since the stop of a vehicle such as a taxi. If set to 100, about 200 seconds (3 minutes) Therefore, by determining the determination value D, it is possible to arbitrarily set the time from the stop until the abnormality is set, that is, the above-described determination time.
As described above, in the embodiment of the present invention, when the position change does not occur for a predetermined determination time or more, it is determined that some abnormality has occurred in the mobile station. It is necessary to set an appropriate time for the determination time.
The matter to be taken into consideration at this time is to prevent an abnormality from being set when the vehicle stops due to a signal waiting or temporary stop as described above.

Here, the general stop time in the case of waiting for a signal or temporarily stopping may be set to 2 minutes at the most, and set to a longer time, for example, 3 minutes. In this case, the determination value D is 200.
On the other hand, when it can be expected that the vehicle needs to be stopped, such as when it is involved in a traffic jam or when passengers get on and off, it is handled by operating the operation unit 25 in advance and inputting stop mode information to the control unit 2. It is possible to prevent abnormalities from being set in cases other than malfunctions and crimes.

It is a block diagram which shows one Embodiment of the mobile communication system which concerns on this invention. It is a block block diagram of the radio | wireless machine in one Embodiment of the mobile communication system which concerns on this invention. 5 is a flowchart for explaining an operation of a mobile station in an embodiment of a mobile communication system according to the present invention. 5 is a flowchart for explaining an operation of a base station in an embodiment of a mobile communication system according to the present invention. It is a block diagram which shows the prior art example of a mobile communication system. It is a block block diagram of the radio | wireless machine in the prior art example of a mobile communication system.

Explanation of symbols

1: Radio unit 2: Control unit 3: GPS unit

Claims (1)

In a mobile communication system comprising a plurality of mobile stations and a base station, performing radio communication with each other, and monitoring an abnormality of the mobile station by the base station,
Position information transmission means for detecting its own position in the mobile station and transmitting position information to the base station;
Computation means for detecting a change in position of the mobile station based on position information received from the mobile station at the base station,
The mobile communication system, wherein the base station is configured to determine that the mobile station is abnormal when the position of the mobile station does not change over a predetermined determination time.

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