JPH0318800B2 - - Google Patents

Description

[Detailed description of the invention]

(Technical Field of the Invention) The present invention relates to a method for reducing the number of installed transmitters in a wide area paging system and reducing unnecessary emission of radio waves in a zone where there is a low possibility that a called party exists. It is something. (Prior Art and Problems) FIG. 1 is a block diagram showing the configuration of a conventional wide area paging system. In the figure, 1 and 2 are calling parties, 3 is an exchange, 4 and 5 are encoding devices, 10,
20 is a service zone (also simply called a zone),
11, 12, 21, 22 are transmitters, 13, 23 are antennas, and 14, 24 are called parties. Transmitter 11
and transmitter 21 have the same transmission frequency (temporarily set to ₁ )
The transmitter 12 and the transmitter 22 also have the same transmission frequency (temporarily set to ₂ ). Now, when the calling party 1 tries to call the called party 14, and assuming that the assigned frequency of the called party 14 is ₁ , the signal issued by the calling party 1 is transmitted through the exchange 3 and added to the encoding device 4. The output signal of the encoder 4 was applied to the transmitter 11 of the zone 10 and the transmitter 21 of the zone 20, and both transmitters converted the signal into a radio frequency and simultaneously emitted it to both zones. In this way, in conventional wide-area paging systems, each zone is equipped with the same number of transmitters as the number of allocated frequencies, and radio waves for paging signals are emitted in all zones, regardless of which zone the called party is located in. Ta. However, if the called party 14, who is a subscriber, is usually in zone 10 and rarely in zone 20, the transmitter 21 in zone 20
It is wasteful to emit a paging signal from. Furthermore, if the number of subscribers existing in zone 10 is significantly larger than the number of subscribers existing in zone 20 when looking at the total number of subscribers, the same number of transmitters as zone 10 are provided in zone 20. There is also the problem that the installation efficiency of the transmitter is poor. (Objective of the Invention) The object of the present invention is to provide a variable frequency synthesizer transmitter (hereinafter simply referred to as a synthesizer transmitter) in each calling zone, and to install the same number of transmitters as the number of allocated frequencies as in the conventional system. By setting a home zone for the subscriber who is the called party and determining the number of transmitters according to the number of users who have set the home zone for each zone, the number of transmitters installed can be optimized. , the called party is called first in the zone where the called party is most likely to be present, and when there is no response, the calling zone is designated sequentially. The aim is to prevent calls from being made and reduce the emission of unnecessary radio waves. (Structure and operation of the invention) The present invention has the following structure in order to achieve the above object. That is, in a wide area paging system having an encoding device and a plurality of transmitters connected to the encoding device, the home zone of each subscriber is determined in advance, and this zone is designated as the home zone for each zone. A number of variable frequency synthesizer transmitters corresponding to the number of subscribers are provided, a control device is provided between each of the transmitters and the encoding device, and under the control of the control device, the first call is made to the home of the subscriber to be called. The second call is a wide area paging method in which the transmission frequency of the transmitter is switched to a radio frequency corresponding to the calling number and a paging signal is transmitted in the paging zone specified by the caller. The present invention has the above configuration and operates as follows. Now, when a caller dials the number of a particular subscriber to call that subscriber, this signal is applied via the exchange to the encoding device and the encoded signal is applied to the control device. In this control device, the assigned frequency and home zone of the called subscriber are determined from the encoding device, and only the transmitter in the home zone is switched to the assigned frequency and operated to transmit a paging signal radio wave. The purpose is achieved if the called party is present in the home zone and answers the call.
On the other hand, if the desired called party happens to exist in a zone other than the home zone, the call cannot be detected because the radio waves transmitted by the transmitter in the home zone cannot be received alone. Therefore, there will be no response. In such a case, the calling party makes a second call, and this time, the calling party specifies a zone in which the called party is likely to be located and makes the call. Same as the first call,
The paging signal reaches the control device via the exchange and the encoding device, where it is determined that it is the second paging and the designated zone, and a control signal is sent to the transmitter to operate the transmitter in the designated zone at the assigned frequency. send to If there is no response to the second call, the same procedure as the second call is repeated. (Embodiments of the invention) Hereinafter, embodiments of the invention will be described based on the drawings. FIG. 2 is a block diagram showing the structure of an embodiment of the method of the present invention in which there are two zones. Numbers 1 to 5, 10, 13, 14, 20, 23, and 24 in the figure are the same as in FIG. 1. 15, 25 are newly provided control devices in the method of the present invention, 19, 26, 27
is a synthesizer transmitter. In this embodiment, the number of subscribers whose home zone is zone 10 is greater than the number of subscribers whose home zone is zone 20. Therefore, there are two transmitters in zone 10 and one transmitter in zone 20. It is a stand. Generally, an optimal number of transmitters is installed depending on the number of subscribers who make each zone their home zone. Now consider the case where calling party 1 calls subscriber 14 whose home zone is zone 10. The calling signal passes through exchange 3,
It enters either the encoding device 4 or 5, which is predetermined by the subscriber's code. Assume that the encoder 4 is now entered. The output signal of the encoding device 4 is applied to a control device 15 of zone 10 and a control device 25 of zone 20. In this embodiment, since the subscriber 14 has the zone 10 as his home zone, the control device 15 tunes the transmitter 19 or 27 to the radio frequency of the subscriber 14 and then sends out a calling signal for the subscriber 14. However, the controller 25 corresponding to zone 20 is
Since 4 is not a subscriber in his zone, transmitter 26
Zone 20 because no command to tune to subscriber 14's radio frequency and no command to send out a paging signal is issued.
No radio waves will be emitted. Subscribers generally register the zone in which they are most frequently present among multiple zones as their home zone, so simply emitting radio waves for a paging signal from the transmitter in the home zone can resolve the purpose of the call. The frequency of achieving this will inevitably increase. This eliminates the need to emit unnecessary radio waves from transmitters in other zones, thereby reducing the emission of unnecessary radio waves. In this embodiment, if the subscriber 14 is within the zone 10, the purpose is achieved with one call and no radio waves are emitted in the zone 20. On the other hand, if the subscriber 14 happens to be present in the zone 20, the subscriber 14 will not be able to sense the call and will not respond if only the radio waves of the calling signal are emitted in the zone 10. Then, the caller 1 receives no response from the subscriber 14 after a certain period of time has elapsed, so the caller 1 then specifies zone 20 and calls the subscriber 14 again, and this time the control device 15 corresponding to zone 10 Rather than commanding transmitters 19 and 27 to emit radio waves, controller 25 corresponding to zone 20 tunes transmitter 26 to the radio frequency of subscriber 14 and then sends out a ringing signal for subscriber 14. FIG. 3 is an example in which a control device 6 having both functions is used in place of the control devices 15 and 25 in FIG. 2, and the same effects as in FIG. 2 can be obtained. In the embodiment shown in Figure 2, it is assumed that the radio waves transmitted by each transmitter will be distributed over the entire area of its own zone, but depending on the topographical conditions of the zone, the installation conditions and area of the transmitting equipment, If the radio waves from the transmitter do not reach the entire zone, install multiple transmitters in appropriate locations that receive the same command from the same control device and operate at the same time, so that the radio waves calling subscribers can spread throughout the zone. It is also done to An example is shown in FIG. i.e. one zone 10
Inside, they receive the same commands from the same control device,
Transmitters 19 and 16 have the same operation, transmitters 12 and 27 have the same operation, and subscriber 14 is in zone 10.
The call signal can now be received no matter where you are in the country. (Effects of the Invention) As explained above, the wide area paging system to which the method of the present invention is applied has the following advantages. First, by adopting a variable frequency synthesizer transmitter as a transmitter, there is no need to install a separate transmitter for each assigned frequency as in the past, and wasteful capital investment can be saved. Second, among multiple zones, by registering the zone where each subscriber is present most frequently as the home zone, it is possible to grasp the call frequency for each zone. The number of transmitters to be installed can be determined accordingly. This, together with the first advantage, makes it possible to set the number of transmitters installed in each zone to a necessary and sufficient number. Third, the first call to a subscriber activates only the transmitter in the subscriber's home zone to emit a paging radio wave, and if there is no response, the paging radio wave is emitted in the next zone according to the caller's specifications. However, since the probability that the subscriber exists in the home zone is high for the reason that the home zone was established, the purpose of the call is often achieved by calling only in the home zone. Therefore, compared to the conventional system in which radio waves are emitted in all zones, the emission of unnecessary radio waves in other zones can be significantly reduced. The method of the present invention has the advantages described above. Hereinafter, the effects of the invention in Examples of the present invention will be shown with specific numerical values. There are two service zones, Zone A and Zone B, and the number of subscribers that can be accommodated per encoding device is
10,000, the total number of subscribers is 30,000, and the number of calls per day to each subscriber is one. In the conventional system, there are three encoders and a transmitter for each encoder, so it is zone A. There will be a total of 6 units, 3 units each in Zone B, and the number of call radio waves emitted will be 30,000 times a day in both Zone A and Zone B. Next, consider a case where the method of the present invention is applied. First, set your home zone. Of the subscribers accommodated in encoding device No. 1, 7000 subscribers have zone A as their home zone, 3000 subscribers have zone B as their home zone, and similarly for encoding device No. 2, the former has 8000 subscribers. , the latter is 2000, and for encoding device No. 3, the former is 9000 and the latter is 1000, then the total number of subscribers whose home zone is zone A is 24000,
The total number of subscribers whose home zone is Zone B is
It will be 6000. The appropriate number of transmitters for this number is Zone A
This means that the number of transmitters in zone B is three, and the number of transmitters in zone B is one, which means that two transmitters in zone B can be saved compared to the conventional system. Next, regarding the number of call radio waves emitted per day, the first call is 24,000 in zone A, and 24,000 in zone B.
So it becomes 6000. In addition, there are two cases where the subscriber is located in another zone instead of his home zone.
If the second call occurs once in 10 times, then the second call in zone A is 6000 x 0.1 =
600, and the second call in zone B is 24000×0.1=2400, resulting in 24600 calls in zone A and 8400 calls in zone B. In the conventional system, each zone was 30,000 times, so for zone A, it was 5,400 times (18%),
For Zone B, unnecessary radio wave emissions will be saved by 21,600 times (72%). If the above is tabulated, it will look like Table 1. As described above, the wide area paging system to which the method of the present invention is applied has the great effect of significantly reducing the number of installed transmitters and the number of times unnecessary radio waves are emitted, compared to conventional systems.

【table】

【table】 [Brief explanation of drawings]

Figure 1 is a block diagram showing the configuration of a conventional wide area paging system, Figure 2 is a block diagram showing the configuration of a first embodiment to which the method of the present invention is applied, and Figure 3 is a block diagram to which the method of the present invention is applied. The fourth is a block diagram showing the configuration of the second embodiment, and the fourth is a diagram showing an example of the transmitter configuration in one zone when the method of the present invention is applied. 1, 2... Caller, 3... Exchange, 4, 5...
... Encoding device, 10, 20 ... Service zone,
11, 12, 21, 22... Fixed frequency transmitter, 13, 18, 23... Antenna, 14, 24...
...Called subscriber, 6, 15, 25... Control device, 16, 17, 19, 26, 27... Frequency variable synthesizer transmitter.

Claims (1)

[Claims] 1. In a wide area paging system that has an encoding device and a plurality of transmitters connected to the encoding device, the home zone of the subscriber is determined in advance, and the subscriber who makes that zone his home zone for each zone. A control device is provided between each of the transmitters and the encoding device, and under the control of the control device, the first call is made only in the home zone of the subscriber to be called. in,
This wide area paging system is characterized in that the second call is made in a paging zone specified by the caller, and a paging signal is transmitted by switching the transmission frequency of the transmitter to a radio frequency corresponding to the paging number.