JPH07240956A - Isdn signal repeating method - Google Patents

Abstract

PURPOSE:To immediately enable B channel communication when a call incoming side terminal off hooks. CONSTITUTION:A setup signal 21 transmitted from a mobile terminal 13 is temporarily stored in a base station side unit 14 and after the end of interleaving between a mobile equipment side unit 12 and the base station side unit 14 and processing 13 peculiar for a mobile communication system for a call originating/terminating procedure, a setup signal 23 is transmitted through an ISDN to a fixed terminal 16. At the fixed terminal 16, the setup signal 23 is received and after a Call Proc signal, Alert signal and Conn signal are returned by a normal processing procedure, the B channel communication can be immediately started.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the influence of another network when setting a communication line through a fixed ISDN network (service integrated digital network) and another network such as a mobile communication network.
That is, the present invention relates to an ISDN signal relaying method in an ISDN outgoing / incoming call procedure when a connection delay occurs due to synchronization, interleaving, outgoing / incoming call processing unique to the network.

[0002]

2. Description of the Related Art In recent years, needs for diversification of mobile communication have been increasing. Conventionally, the form of mobile communication is shifting from the form of mobile communication, which was mainly telephone, to various needs including non-telephone type communication such as image communication and data communication. In the mobile communication system of ISDN service, Offering is about to be attempted.

In a mobile communication system mainly for voice transmission, the wireless section signal transmission quality is extremely poor as compared with the fixed ISDN transmission quality. That is, fixed ISDN
In contrast, a bit error rate of 10 ⁻⁶ or less is provided, whereas a bit error rate for obtaining a voice quality that is acceptable in mobile communication is about 10 ⁻² . Therefore, a fixed ISD is used in a mobile communication system mainly for voice transmission.
In order to provide an ISDN service with a signal transmission quality equivalent to N, it is inevitable to apply a quality improvement technique such as an error correction code. Such a method for providing high-quality facsimile communication or modem communication by interposing a function for improving quality (hereinafter, referred to as a unit) in a mobile radio section has already been practically used (Reference, Uebayashi, Sawai, Nagata, Ishino, "Digital mobile communication system: Non-telephone signal transmission service" NTT DoCoMo Technical Journal V
ol. 1, No. 1, pp. 47-49, Jul. 19
93).

In the case of using such a unit to provide an ISDN service in a mobile communication system, the unit which is a function on the network side assigns a demand (when the user requests the ISDN communication, the unit intervenes. It can be said that it is desirable to use the above in order to improve the efficiency of unit device operation. In this case, it is necessary to establish synchronization between the units within the poor transmission quality as described above from the time the units are allocated until the B channel communication actually becomes possible, which requires time. become. Further, if interleaving is applied in order to randomize burst errors occurring in the wireless section and bring out the performance of the error correction code, a delay time for this purpose will occur. In addition, the normal ISDN defined incoming / outgoing call procedure (for the ISDN normal incoming / outgoing call procedure, see CCIT
In addition to the T recommendation, there may be a case where a procedure specific to the mobile communication system is required (for details, refer to References, Yamamoto, Takamura, Uchida, Hirata, "Digital Mobile Communication System: Network Configuration and Signaling System"). NTT DoCoMo Technical Journal Vol.1, No.1, pp.20-2
2, Jul. 1993), and time will be needed for these.

For example, as shown in FIG. 2, a mobile terminal 13 is connected to a mobile communication system 11 via a mobile unit 12 and the mobile communication system 11 is connected to a fixed ISDN network 15 via a base station unit 14. A system is conceivable in which the mobile terminal 13 is connected and the mobile terminal 13 is connected to the fixed terminal 16 via the mobile communication system 11 and the fixed ISDN network 15 to perform various communications with each other.

In such a system, when a setup signal (corresponding to a transmission request) 21 for transmission is transmitted from a transmission side terminal, for example, the mobile terminal 13, as shown in FIG. Unit 12 is the se
Mobile communication system 11 for notifying the tup signal 21 to the terminating side unit, in this example, the base station side unit 14.
Signal 22 within. Upon receiving the signal 22, the base station side unit 14 immediately sends out a setup signal 23 to the fixed terminal 16 which is the receiving side terminal. Fixed terminal 16 is se
Upon receipt of the tup signal 23, the Call Proc signal 24, A
The lert signal 25 and the Conn signal 26 corresponding to the off-hook are sent to the base station side unit 14 (Call
The Proc signal 24 is an option, so some terminals do not output it).

[0007]

Since the Call Proc signal 24 and the Alert signal 25 do not require a response from the network side, the network side cannot control the progress of the protocol at the called terminal. However, as described above, in the wireless section, processing unique to the mobile communication system for the synchronization and interleaving between the mobile unit 12 and the base station unit 14 and the originating and terminating call procedure, that is, the network sets the communication line. Since the delay due to the processing 27 required for the unavoidable processing is unavoidable as shown in FIG. 3, the receiving side unit (base station side unit 14) is set to the receiving side terminal (fixed terminal 1).
Even when the Conn signal 26 from 5) is received, there is no guarantee that the B channel is established, the line setting process 27 is not completed, and the called terminal 14 goes off-hook.
There is a drawback that the B channel communication cannot be performed immediately. In the worst case, the timer of the called terminal 14 from the transmission of the Conn signal 26 to the establishment of the B channel may time out and the called terminal 14 may disconnect the line.

As described above, the object of the present invention is ISDN.
The above problem caused by the connection delay caused by the influence of the other network when setting the communication line through the network and the other network is solved, and the communication of the B channel is immediately performed when the called terminal goes off-hook. Another object of the present invention is to provide a method of relaying an ISDN outgoing / incoming signal that enables communication.

[0009]

According to the present invention, the processing in the other network necessary for temporarily accumulating the setup signal transmitted from the originating terminal in the other network and relaying the B channel signal. After the above, the setup signal is sent to the called terminal.

[0010]

With such a configuration, B channel communication is immediately possible when the called terminal goes off hook. Then, from the receiving side terminal, it seems that the protocol is proceeding in exactly the same manner as the normal outgoing / incoming call procedure.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a case where a communication line is set up via a fixed ISDN network and a mobile communication network as another network will be described with reference to FIG. Therefore, the system configuration to which this embodiment is applied is the same as that shown in FIG. 2, for example. Similar to the case of FIG. 3, for example, the mobile terminal 13
1 sends a setup signal 21 to originate a call, as shown in FIG.
The mobile communication system 11 for notifying the base station side of the setup signal 21 from the mobile unit 12 as shown in FIG.
The internal signal 22 is transmitted to the base station side unit 14. The base station unit 14, that is, the processing 27 for temporarily accumulating the notification signal 22 received in the mobile communication network, that is, the setup signal, and relaying the B channel signal in the mobile communication system 11, that is, the mobile unit 12 and the base. After the processing unique to the mobile communication system 11 for the synchronization and interleaving with the station side unit 14 and the call originating / receiving procedure is completed, the base station side unit 14 sends a setup signal 23 to the called side terminal, that is, the fixed terminal 16. Send out. Fixed terminal 1
When receiving the setup signal 23, the 6 sends an exactly the same incoming procedure as the normal incoming procedure, that is, the Call Proc signal 24, the Alert signal 25 and the Conn signal 26 to the base station side unit 14. The base station unit 14 is C
When the onn signal 26 is received, the confirmation signal Conn
The Ack signal 28 is returned to the fixed terminal 16 and the fixed terminal 16
Communication between the mobile terminal 13 and the mobile terminal 13 becomes possible.

According to this embodiment, if the fixed terminal 16 goes off-hook, the communication channel between the units 13 and 14 is set at that time, so that the B channel communication can be performed immediately. Although the case where the mobile terminal 13 starts moving has been described above, even when the fixed terminal 16 makes a call, the base station side unit 14 or the mobile unit side unit 12 causes the fixed terminal 1 to move.
Temporarily compensate the setup signal from 6 and
It may be sent to the mobile terminal 13 after the setting processing of the B channel line between the No. 2 and 14 is completed. In the above, setu
Although the p signal is temporarily stored in the base station side unit, it may be temporarily stored in the mobile unit side unit. Furthermore, the communication line was set up via the fixed ISDN network and the mobile communication system, but not only the mobile communication network but also the satellite communication network and other fixed ISDN networks.
The present invention can be applied to signal relay of an ISDN call originating / receiving procedure in a system in which a connection delay occurs due to the influence of the other connected network when the network is connected to another network to set up a line.

[0013]

As described above, according to the present invention, the IS signal is temporarily stored in the called side network and IS
Since the setup signal is sent to the receiving side terminal after the line setting process of the B channel communication between the DN network and another network is completed, the B channel communication can be performed immediately when the receiving side terminal goes off hook. From the terminating side terminal, it seems that the protocol is proceeding in exactly the same manner as the normal outgoing / incoming call procedure. The timer of the called terminal times out and the called terminal does not disconnect the line.

[Brief description of drawings]

FIG. 1 is a diagram showing a processing procedure in an embodiment of the present invention.

FIG. 2 is a block diagram showing an example of a system targeted by the present invention.

FIG. 3 is a diagram showing a conventional processing procedure and its problems.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI Technical indication location H04Q 7/30 H04L 12/02 H04M 3/00 C 7406-5K (72) Inventor Akira Hiroike Tokyo 2-10-1 Toranomon, Minato-ku NTT Mobile Communications Network Co., Ltd.

Claims (2)

[Claims] 1. An ISDN signal relay method in an ISDN outgoing / incoming call procedure when a connection delay occurs due to the influence of the other network when a communication line is set up through a fixed ISDN network and another network. The setup signal sent from the terminal is temporarily stored in the other network, and the setup signal is sent to the called terminal after the processing in the other network for relaying the B channel signal is completed. A characteristic ISDN signal relay method. 2. The ISDN signal relay method according to claim 1, wherein the other network is a mobile communication network.