JPH029239A - Multi-channel access communication system - Google Patents

Abstract

PURPOSE:To attain communication to an urgent call from a mobile station by adding a forced call request to a call signal from a mobile station and switching the communication time in short when forced call processing is applied or S-ch (speech circuit) congestion is detected by a line controller. CONSTITUTION:When all S-ch are in use when a call signal is sent by using a C-ch (control line) 9a11 from a mobile station 7ax and a call from the mobile station 7ax is urgent, the mobile station 7ax sends a forced call request call signal added with a forced call request to the line controller 5a through the S-ch9a2. The line controller 5a receiving the forced call request call signal through the S-ch9a2 terminates the S-ch8a1 to be registered in advance with low priority through the C-ch9a2 forcibly and the ch designation signal is sent by using the C-ch9a. When mobile stations 7ax, 7ay receive the ch designation signal, the transmission and reception frequency of its own station is matched with the frequency of the designated S-ch8a1 and the mobile stations 7ax, 7ay use the S-ch8a1 to attain communication.

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to a multi-channel access communication system in which a call is forced only to a specific mobile station when all mobile stations are in use.

[Conventional technology]

Figure 4 shows conventional multi-channel access (hereinafter referred to as MC).
In the figure, 1 is a monitoring device, 2a is a 2-bit modem, 3 is a dedicated line, 4 is a DC branching device, and 5a.

5b is a line control device, 6a1, 6a2. =-6an
, 6b1, 6b2.

...6bn is the transmission/reception device of each line control device 5a, 5b, 7al, 7a2+...7am, 7b1, 7b2
,=4bm is a mobile station, 8a1-8ap, 8bl"
' abq is S ch s 9 a * 9 b is a control (b) line (hereinafter referred to as C-ah). Next, the operation will be explained. When the mobile station 7a1 makes a call, the calling signal passes through the C-chsa, is received by the C-chsa transmitter/receiver 6al, and is transmitted to the line controller 5a.

The line control device 5a searches for a vacant 5-ch and
A is used to transmit a channel designation signal.

When mobile stations 7a1 and 7a2 receive the ah designation signal, they adjust their own transmitting and receiving frequencies to the designated frequency of 5-ch 8al, and thereafter mobile stations 7al + 7a2 transmit 5-ch 8.
You can make calls using a1.

On the other hand, the monitoring device 1 and the line control devices 5a and 5b are connected to the modem 2.
A and 2b are connected to each other by a dedicated line 3 and a DC branching device 4, so that the operational status of the line control devices 5a and 5b can be constantly monitored and controlled.

[The problem that the invention aims to solve]

The conventional MCA communication system is configured as described above, so if all 5-channels are in use, new calls cannot be accepted until any 5-channel is terminated. However, there was a problem in that even in an emergency, you may have to wait.

This invention was made to solve the above-mentioned problems, and it is possible to make a call in an emergency from a mobile station even when all 5-channels are in use.
The purpose is to obtain a CA communication system.

[Means to solve the problem]

The MCA communication system according to the present invention allocates 5-ah preferentially to a specific mobile station that makes an emergency call even when all 5-ch is used, or reduces the congestion of 5-Ch. It is equipped with a line control device that shortens the call time when it is detected.

[Effect]

When the forced call request data is added to the call signal from the mobile station in this invention, the line control device that receives the data forcibly terminates the 5-ah call that is in progress and responds to the call with the forced call request. If 5-ch is assigned preferentially or if the line control device detects 5-ahO congestion, the call time is shortened.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. 1st
In the figure, 5a is a line control device, 6a1゜6a2...
・6an is the transmitting/receiving device, 7al, 7a2.7a3 +
7a4 +...7ax+γay is a mobile station, 8a1.8
a2*=-8ap is 5-ch, and 9a is C-ch.

Note that the monitoring device 1, modem 2ae2b,
The system of the dedicated line 3, the DC branching device 4, the line control device 5b, the transmitting/receiving devices 6a1 to 6bns, and the mobile stations 7b1 to 7bn is not illustrated.

FIG. 2 shows line control equipment 5a1 to mobile stations 7a1 to 7ax+.
It is a sequence diagram of C-ch between Tay, 9a11
+9a12, 9a2.9a4 are 5-ch.

Next, the operation will be explained. As shown in FIG. 1, mobile station 7a1+7a2Ja3+7a4- has S ch 8a1.
．． Assume that 8a2s=8ap are all allocated.

Here, as shown in FIG. 2, assume that the mobile station 7ax newly sends out a call signal using C-ch 9au.

At this point all 5-ahs are in use, mobile station 7a
The call request from x sends C-ah 9a12, but
You will have to wait.

If the call from mobile station 7ax is an emergency, mobile station 7
ax sends a call signal with a forced call request added to the line control device 5a to 5-ch 9a2. The line control device 5a, which received this call signal with forced call request through 5-ah 9a2, forcibly terminates the call to 5-ah 8a1, which has a low priority registered in advance through C-ah 9a3, and uses C-ch 9a. and sends an ah designation signal.

When mobile stations 7ax and 7ay receive the channel designation signal, they adjust their own transmitting and receiving frequencies to the designated frequency of 5-ch8al, and from then on, mobile stations 7ax + 7ay change to 5-ch8a.
You can make calls using 1.

In the above embodiment, the call signal processing at the time of S-ch congestion was shown by forced calling and forced termination.
When congestion is detected, the call duration may be shortened to provide a wider opportunity to talk.

That is, as shown in FIG. 3, in the line control device 5a, the usage rate of 5-ah is constantly monitored in step STI, and when the 5-ch usage rate reaches a certain level (N%) or more, the usage rate of 5-ah is monitored in step ST2. 5-chi call maximum time T is shifted from step ST2 to step ST3 and changed from T1 to T2.
(However, Tt > T2).

Further, in step STI, when the 5-ch usage rate falls within a certain level (N%), the process moves from step STI to step ST4, and in step ST5, the 5-ch usage rate is within a certain level (N%).
Maximum call time T from step ST4 to step ST5
, and return from T2 to T1.

〔Effect of the invention〕

As described above, according to the present invention, when a forced call request is added to a call signal from a mobile station and forced call processing is performed or when 5-ch congestion is detected by the line control device, the call time is 5-chfi
This has the effect of receiving an emergency call signal when an i-book is available.

[Brief explanation of the drawing]

FIG. 1 is a system configuration diagram of the main parts of the MCA communication system according to an embodiment of the present invention, FIG. 2 is a sequence diagram of the C-ch between a line control device and a mobile station in the same embodiment, and FIG. FIG. 4 is a flowchart showing the operation flow of the MCA communication method according to another embodiment of the invention, and is a system configuration diagram of the conventional MCA communication method. 1 is a monitoring device, 5a is a line control device, 6a1 to 6an are transmitting/receiving devices, 7a1 to 7ax, 7ay are mobile stations, 8a1
~8ap+9a2.9a4.9a11.9a12 is 5-
ch, 9a, 9a3 are Cch. In addition, the same symbols in the figures indicate the same or equivalent parts.

Claims (1)

[Claims] When a channel is specified, it becomes possible to communicate according to the frequency of the specified telephone line, and when all the telephone lines are allocated, it is possible to output a call signal with a forced call request when an emergency call is necessary. When receiving a call signal with a forced call request from a plurality of mobile stations, the system forcibly terminates a low-priority call line through a predetermined control line or detects congestion on the call line. A multi-channel access communication system that includes multiple line control devices that shorten call time and a monitoring device that monitors and controls the operational status of the multiple line control devices.