JPS58103241A - Display system outside service area of selective call receiver - Google Patents

Abstract

PURPOSE:To discriminate the service area of the own selective call transmitter and to perform a display with no error, by transmitting a synchronous signal and an individual selection signal from a master station and then detecting with demodulation the individual selection signal at a slave station. CONSTITUTION:The electric wave given from a base station is received at a car telephone radio device 1, and a switch 4 is started to transmit the signal of a word obtained by 1-bit synchronism + word synchronism + individual number and + information is transmitted to a selective call receiver (slave station) 3 from a selective call transmitter (master station) 2. The signal given from the transmitter 2 is demodulated by a radio device 12 of the receiver 3, and the information part of a data string is decided by an incoming call signal detecting part 13. At the same time, the word synchronizing part is decoded at a word synchronism detecting part 16. Thus the synchronism is obtained for the words, and the individual number part is decoded at a selection signal detecting part 17 to collate a prescribed individual number. The outputs of the parts 16 and 17 are applied to a control part 18. Then the outside of the service area is displayed when it is impossible to receive a prescribed individual number for a certain period or more.

Description

[Detailed description of the invention] The present invention relates to an out-of-service area display method for a selective calling receiver.

The out-of-service area display system of the conventional selective call receiver is configured to determine whether the receiver is outside the service area by detecting an electric field or a word synchronization signal, and to display the result.

This method is an effective out-of-range display method for general paging systems. However, when used in a car telephone radio system, Kept has the disadvantage that it cannot be distinguished from the service area of other selective call transmitters.

Here, a method for indicating that a selective call receiver is out of service area in a car telephone radio system will be explained.

In a car telephone radio system, when a general subscriber calls a car phone subscriber (hereinafter referred to as an incoming call), a method is generally used in which a ringing tone is produced by a speaker. However, in consideration of the case where the user is away from the car, the Kf1 is designed to sound the car's pawn or flash the car's lights when a call arrives.
A method using a selective call receiver is used.

As shown in FIG. 1, the method using a selective call receiver consists of a selective call transmitter 2 connected to a car telephone radio device 1 and a portable selective call receiver 3, and is used to receive a call to the car telephone radio device. , and the activation permission switch 4 for selective calling is enabled, the selective calling transmitter 2 is activated from the incoming call.
This service notifies the mobile phone subscriber of an incoming call by activating the mobile phone subscriber who is away from the car and making a reception display sound on the selective call receiver 3 carried by the mobile phone subscriber who is away from the car.

Therefore, if this method is adopted, it is important to know to what extent the service will be provided when the subscriber leaves the car.

However, in the conventional method of determining whether the car is out of the area by detecting the word synchronization signal, as shown in FIG. If the same frequency is used when using a car phone radio *ii7 selective call reception m
Although it is only within the 9fl service area 10, when the user moves to position 9', he mistakenly recognizes the service area of the car 6 telephone radio device as his own service area.

This possibility is even more dire in large cities where car phone service is highly utilized. Although there is a method of using different frequencies for each car phone subscriber to avoid misrecognition of the service area, it is virtually impossible to use different frequencies from the standpoint of effective frequency utilization.

SUMMARY OF THE INVENTION An object of the present invention is to provide an out-of-service display system for a selective call receiver that solves the above-mentioned drawbacks and makes it possible to distinguish the service area of one's own selective call transmitter from other selective call transmitters.

In order to achieve the above object, the present invention provides a method for indicating that a selective call receiver is out of the service area of a selective call receiver (c) A method for displaying this on the selective call receiver when the selective call receiver is out of the service area of a selective call transmitter. , from the selective call withdrawal 048, a word synchronization signal for synchronizing one word of the data string, an individual selection signal for specifying the selective call transmitter, and information indicating incoming calls, unincoming calls, etc. from the base station. On the other hand, the selective call receiver performs word synchronization using the word synchronization signal, determines whether the individual selection signal is a signal from the corresponding selective call transmitter, and selects a predetermined signal. The device is configured to display an out-of-service-area message when the individual selection signal cannot be received for a certain period of time or more.

Hereinafter, the present invention will be explained in more detail with reference to the drawings and the like. FIG. 3 is an example of a data string used in the out-of-service area display method of the selective calling receiver according to the present invention. Start permission switch 4t
When turned on, the selective call transmitter 2 (hereinafter referred to as the master station) transmits a signal consisting of (1 bit synchronization + word synchronization + individual number 10 information) continuously or in bursts to the selective call receiver 3 (
Hereinafter, slave station) K is transmitted. A signal for synchronizing the word is inserted into the word synchronization area from the free run state. A number indicating the master station transmitting the data string is inserted into the individual number area. The information area also includes an incoming call code if there is an incoming call, and a missed call code if there is no incoming call.

FIG. 4 is a circuit block diagram showing an embodiment of the master station.

The radio section 12 demodulates the signal from the master station 3. Incoming call signal detection unit 13 decodes the information part of the data string and detects whether there is an incoming call.

The word synchronization detection section 16 decodes the word synchronization section and synchronizes the words. The selection signal detection unit 17 decodes the individual number part and checks whether it is a predetermined individual number. The control unit 18 has a counting function, and the word synchronization detection unit 16
, the incoming call signal detection unit 1 is detected by the output of the selection signal detection unit 17.
3 and controls the sound generator. 15 is a sounding body.

When there is an incoming call to the car telephone and a data string containing an incoming call code is sent, the output of the word synchronization detection section causes the control section 18Fi to enable the incoming call signal detection section 13 to receive the call. When the individual selection signal detection section 17 detects a predetermined selection signal, it outputs a permission signal for generating a ringing tone to the ringing tone generation section 14. When the incoming call code is detected by the incoming call signal detection unit 13, the sound generator 14 is activated and the sound generator 1
5 outputs a ringing tone to notify the user of an incoming call.

If there is no incoming call and a missed call code is detected, the sound generator 14 is not activated. On the other hand, outputs detected by the selective call signal detection section 17 and matched with a predetermined selection signal are counted by the control section 18. Then, if the predetermined number of times is not counted within a predetermined time, that is, if you are out of the service area of the master station, the sound generator 14 is set so that it can emit an alarm tone with a tone different from the ring tone that notifies you of an incoming call. Start,
An alarm sound is made to sound from the sounding body 15.

As explained in detail above, according to the present invention, by sending out a synchronization signal and an individual selection signal from a master station, and demodulating and detecting the individual selection signal at a slave station, it is possible to display without error whether or not it is within its own service area. can.

[Brief explanation of the drawing]

Figures 1 and 2 are schematic diagrams for explaining the car telephone radio system.
This shows a case where the service areas of two mobile objects overlap. FIG. 2 is a schematic diagram of a data string received by a selective call receiver, and FIG. 3 is a circuit block diagram showing an embodiment of a selective call receiver configured according to the method of the present invention. 1... Car telephone radio device 2... Selective call transmitter (master station) 3.8, 9... Selective call reception all! (Slave station) 4...
・Activation permission switch 5... Base station 6.7... Mobile object (car) 10, 11... Service area 12... Radio device 13... Incoming call signal detection unit 14... Ringing sound Generating part 15
...Sounding body 16...Word synchronization detection unit 17...
・Selection signal detection unit 18...Systems Department Patent applicant NEC Co., Ltd. agent Patent attorney Hisashi Inoro (2nd figure, 3rd figure, 4th figure, procedural amendment format) April 2, 1982) Japan Patent Office Commissioner Shima 1) Toshiharu Haruki 1, Indication of Case Patent Application No. 202799 of 1982 2, Invention Name Selective Calling Receiver Out of Service Area Indication Method 3, Relationship with the Amendment Person Case Patent Applicant 4, agent changed the statement "Figure 2" on the third line of page 8 of the specification to "Figure 3" and changed the statement "Figure 3" on the fourth line to [Figure 4]. correct.

Claims (1)

[Claims] When the selective calling receiver is out of the service area of the selective calling transmitter, in the method shown by the selective calling receiver Kfi, the selective calling transmitter sends a word for synchronizing one word of the data string. No. 46 consisting of a synchronization signal, an individual selection signal identifying the selective call transmitter, and an information signal indicating incoming calls, missed calls, etc. from the base station, while the selective call receiver transmits the word synchronization signal. In addition to word synchronization, it is determined whether the individual selection signal is a signal from a corresponding selective call transmitter, and when a predetermined individual selection signal cannot be received for a certain period of time or more, an out-of-service area display is performed. Features an out-of-service-area display method for selective calling receivers.