JPH04326893A - Exchange system capable of receiving radio subscriber terminal - Google Patents

Abstract

PURPOSE:To offer an exchange system which can deal with the frequent switching of a channel during communication, and can receive radio subscriber terminal to a line interface receiving part where a wired subscriber terminal is received, and can mix and receive a wired system excellent in extendability and economical efficiency and a radio system. CONSTITUTION:A radio subscriber terminal interface means 16 which receives a radio base station 50 to communicate with the corresponding subscriber terminal in a zone by radio and interfaces this radio subscriber terminal, a switching means 20 for mobile control which is connected to plural radio subscriber terminal interface means 16, and switches and controls the radio subscriber terminal interface means in conformity to a switching instruction, and a call control means 18 for mobile control which instructs the switching of the switching means 20 for mobile control when the radio subscriber terminal 60 moves between the zones of plural radio base stations 50 during the communication so that the communication following the movement between the radio base stations 50 is made possible are provided.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a switching system, and more particularly to a switching system capable of accommodating mobile communication terminals such as cordless telephones via radio base stations.

0002

2. Description of the Related Art In recent years, in offices and the like, an increasing number of cases are being provided to each employee with an extension telephone housed in a private branch exchange or the like in order to improve work efficiency. In this way, when each employee is handed a phone, cordless phones are more portable and can be easily carried around even on short trips, rather than wired phones that are fixed to desks like before. desired. Private branch exchange systems for mobile communications that accommodate such cordless telephone terminals have conventionally included systems that housed cordless subscriber circuits in the line interface accommodating section (line trunk module), and systems that connected cordless subsystems to the exchanges to provide cordless services. There was a system that provided

For example, in the conventional technology in which a cordless subscriber circuit is housed in a line trunk module along with a wired subscriber circuit, a central processing unit that performs wireline call processing and is housed in a private branch exchange performs tasks such as zone switching. Call processing unique to mobile communications is performed. That is, when a cordless telephone terminal moves between zones of multiple wireless base stations connected to a cordless subscriber circuit during a call, a channel switching request from the cordless terminal is sent to the central processing unit, and the central processing unit Communication channels of wireless base stations were switched via a time division switch. Mobile communication systems that are generally applied to private branch exchanges and the like often have a microzone configuration. For this reason, the central processing unit has had to frequently switch channels during communication as the communication terminal moves.

[0004] Furthermore, when an independent cordless subsystem is connected to a private branch exchange and accommodates a plurality of wireless base stations for cordless terminals, communication within the cordless subsystem is interrupted when a channel switching request is received from the cordless telephone. Switch channels. Therefore, the central processing unit of the exchange did not need to perform call processing specific to mobile communication, and could perform call processing for mobile communication terminals in the same way as for wired terminals.

[0005]

[Problems to be Solved by the Invention] For example, in the conventional technology in which a cordless subscriber circuit is housed in a line trunk module of a private branch exchange, when a large number of channel switching requests are received from cordless terminals, it is difficult to reduce the processing capacity of the central processing unit. Therefore, it has been difficult to switch channels at high speed. In other words, with this conventional technology, the line interface accommodation section can accommodate cordless subscriber circuits as well as wired subscriber circuits and central office line trunks, but it is difficult to avoid the frequent switching of channels during calls, which is typical of mobile communication with a micro zone configuration. The disadvantage was that it was not able to respond to In addition, conventional technology in which an independent cordless subsystem is housed in an exchange can support frequent channel switching during calls, but cannot accommodate a mix of wired interface circuits and cordless subscriber circuits in the line interface housing. First, since the cordless subsystem must be installed independently of the wired line interface accommodating section, it lacks versatility and economic efficiency. Furthermore, in this case, when a plurality of cordless subsystems are housed in an exchange, it is not possible to switch the communication channels between the subsystems, resulting in a lack of expandability.

[0006] The present invention overcomes these drawbacks of the prior art, can cope with frequent switching of channels during calls, and can accommodate wireless subscriber terminals in the line interface accommodation section in which wired subscriber terminals are accommodated. The purpose is to provide a flexible exchange system.

[0007]

[Means for Solving the Problems] In order to solve the above-mentioned problems, the present invention accommodates a plurality of wired and wireless subscriber terminals, and performs switching control associated with call connections between the subscriber terminals as a main call. A switching system capable of accommodating wireless subscriber terminals operated by a control means and a main switch means, accommodating a wireless base station that wirelessly communicates with wireless subscriber terminals within a zone,
a wireless subscriber terminal interface means for interfacing with a wireless subscriber terminal; a movement control switch means connected to a plurality of wireless subscriber terminal interface means and controlling switching of the wireless subscriber terminal interface means according to a switching instruction; When a wireless subscriber terminal moves between zones of a plurality of wireless base stations during communication, it instructs the movement control switch means to switch, and enables communication as it moves between wireless base stations. and call control means.

The switching system according to the present invention also includes a wired interface means and a wireless interface that accommodates a wireless base station that wirelessly communicates with wireless subscriber terminals in the zone and interfaces with the wireless subscriber terminals. a general-purpose slot in which any one of the means is mounted; and a movement control switch means for controlling switching of the wireless subscriber terminal interface means in accordance with a switching instruction when the wireless subscriber terminal interface means of the wireless system is mounted in the general-purpose slot. , relays and distributes wired and wireless call control information between the interface means installed in the general-purpose slot and the main call control means, and also relays and distributes call control information for wired and wireless systems between the interface means installed in the general-purpose slot and the main call control means, and also relays and distributes call control information for wired and wireless systems between the interface means installed in the general-purpose slot and the main call control means. It has a mobile control call control means that instructs the mobile control switch means to switch when moving, and enables communication between radio base stations as the mobile station moves.

[0009]

[Operation] According to the present invention, when a wireless subscriber terminal moves between zones of a plurality of wireless base stations during communication, switching control of the movement control switch means is performed to connect to the base station of the movement destination. Do the following.

0010

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of a switching system capable of accommodating wireless subscriber terminals according to the present invention will be described in detail with reference to the accompanying drawings.

Referring to FIG. 2, there is shown a system configuration diagram when the switching system capable of accommodating wireless subscriber terminals according to the present invention is applied to a digital private branch exchange. The private branch exchange 1 is a general analog telephone, a multifunction telephone, or an I
It accommodates a plurality of wired subscriber terminals 70 such as SDN terminals and a wireless subscriber terminal 60 via a wireless base station 50, and the station line side thereof is connected to a public network of an analog line or a digital line such as ISDN, Exchange processing is performed between these terminals or between a terminal and a central office line. The wireless base station 50 is
This is a base station that exchanges voice signals and control signals with the cordless telephone 60, which is a wireless subscriber terminal, through a micro zone, and the cordless subscriber circuit 16 (
(see Figure 1). The wireless base stations 50 are arranged at predetermined intervals so that communication can be performed even if the cordless telephone 60 moves between zones during communication. FIG. 1 shows a functional block diagram of an embodiment in which the present invention is applied to such a private branch exchange.

The private branch exchange 1 in this embodiment has line trunk modules 10-1 to 10- as shown in FIG.
n, time division switch 30 and central processing module 40
has. Each line trunk module 10 is
It is a line interface housing unit that can accommodate wired and wireless systems, and has multiple universal slots (US0 to U
Sn) 12, a cordless controller 18, a cordless switch 20, and a highway interface controller 22. Universal slot 12 is comprised of a wired interface circuit 14 that interfaces with highway 100 and control bus 102 and a cordless subscriber circuit 16 that interfaces with cordless control bus 110 and cordless highway 112.

The wired interface circuit 14 includes a wired terminal subscriber circuit such as a general analog telephone, a multifunction telephone, an analog data terminal, or an ISDN data terminal;
It accommodates office line interface circuits such as office line trunks or ISDN lines, conference trunks, paging trunks, voice guidance trunks, service trunks that interface with relay boards, and the like. That is, when the wired interface circuit 14 accommodates a multi-function telephone, for example, a multi-function telephone interface circuit is used, and when an ISDN line is accommodated, an ISDN interface circuit that provides an ISDN primary group interface is used, and a central office line When accommodating trunks, interface circuits for bidirectional office line trunks are used. Each wired interface circuit 14 is connected to the time division switch 30 via a highway 100, which is a time division multiplexed path having a transmission capacity of 2M bits, and to the highway interface controller 22 via a control bus 102.

The cordless subscriber circuit 16 is a subscriber circuit that accommodates a plurality of wireless base stations 50 and provides a signal interface with the base stations 50. Each cordless subscriber circuit 16 is connected to a cordless controller 18 via a cordless control bus 110 and to a cordless switch 20 via a cordless highway 112, which is a time division multiplexed path having a transmission capacity of 2M bits. Cordless switch 20 is a time division switch for movement control that performs switching between wireless base stations 50 when cordless telephone 60 moves across multiple wireless base stations 50 during communication. Cordless switch 20 is connected to time division switch 30 via highway 100 to realize call connection.

The cordless controller 18 mainly manages the movement of the cordless terminal 60 and controls the movement of the cordless terminal 60.
The cordless switch 20 is controlled in response to a request for switching the active channel between the wireless base stations 50 from the wireless base station 0 to the wireless base station 50. That is, the cordless controller 18 is connected to the central processing module 40 via the highway interface controller 22, and terminates control information from the central processing module 40 and transmits it to the cordless subscriber circuit 16. The station 50 and the cordless terminal 60 are controlled and managed. Cordless controller 18 also terminates control information received from wireless base station 50 or cordless terminal 60 via cordless subscriber circuit 16, and autonomously performs control according to a predetermined processing procedure. This allows the line trunk module 10
A process of switching channels during calls between the radio base stations 50 accommodated within the network is performed. The cordless controller 18 further transfers control information associated with the exchange process to the central processing module 40 via the highway interface controller 22, and also transfers control information associated with the exchange process to the central processing module 40 when the cordless terminal 60 moves to the zone of the wireless base station 50 of a different line trunk module 10. It also exchanges control information with the central processing module 40 so that the communication channel can be switched and the call can be continued.

FIG. 3 shows the backboard wiring of the line trunk module 10 in this embodiment. The universal slot (US0 to USn) 12 is a control bus (PP bus) 10 of the wired interface circuit 14.
2 and the time division switch 30. Therefore, access to the time division multiplex (2MHW) 100 is possible without being affected by the cordless subscriber system. In this embodiment, each line interface module US is also shown in FIG. The backboard is wired as shown, and the cordless controller (CCNT) 18 and cordless switch (
CSW) 20. Note that the universal slot 12 is equipped with either a wired interface circuit 14 or a cordless subscriber circuit 16.

Returning to FIG. 1, the interface controller 22 is a control circuit that relays control information among each component within the line trunk module 10. That is, the controller 22 is connected to the wired interface circuit 14 via the control bus 102 and to the cordless subscriber circuit 1 via the cordless controller 18.
6, and relays control information between these circuits and the central processing module 40.

The time division switch 30 is a line trunk 1
This is a main switch that forms a communication path between terminals or trunks accommodated within 0 or between line trunks 10. The time division switch 30 is connected to a central processing module 40, and performs switching processing in a time division multiplexing manner according to connection control instructions from this module 40. The central processing module 40 is a main control device that controls each component of the exchange 1, and has a function of executing connection control according to a call processing program. Note that in this embodiment, the wireless base stations 50 between different line trunk modules 10
Zone switching is performed via the central processing module 40, but in reality, the base station 50 is arranged so that the cordless terminal 60 moves within the zone of the wireless base station 50 accommodated within the same line trunk 10. will be established. Therefore, the central processing module 40 does not frequently switch channels during communication, and as a result, the central processing module 40
The load on 0 will not increase.

Next, the operation when the cordless terminal 60 moves to another wireless zone during a call will be described. Note that channel switching processing when the cordless terminal 60 moves from wireless zone A of the wireless base station 50A to wireless zone B of the wireless base station 50B accommodated in the same line trunk module 10 will be described here.

Since the cordless terminal 60 constantly monitors the received electric field strength, for example, from zone A to zone B,
, it is detected that the electric field from the wireless base station 50 in zone A becomes weaker and the electric field from the wireless base station 50 in zone B becomes stronger. Cordless terminal 60 transmits a channel switching request to zone B to radio base station 50 in zone A when the received electric field strength of the zone in use becomes weak. Radio base station 50 notifies cordless controller 18 of this switching request via the connected cordless subscriber circuit. If there is an empty channel in zone B, the cordless controller 18 notifies the requesting cordless terminal 60 via the base station of zone A of permission to switch the channel to zone B, controls the cordless switch, and switches the communication channel. Process.

[0021] The cordless switch 20 can connect multiple voices from the other party of the cordless terminal 60 in Zone A and Zone B, mixes the voices of Zone A and Zone B to which the cordless terminal 60 belongs, and selects the one with the voice to make a call. It has the ability to connect to other parties. Since the cordless switch 20 has such a function, in this embodiment, there is a time difference between the call path switching inside the exchange when switching channels and the cordless terminal 60 that has received channel switching permission when switching from zone A to zone B. Even if this occurs, instantaneous call interruptions can be minimized.

[0022] As described above, in the above operation example, an example has been described in which the cordless terminal 60 monitors the received electric field strength, but the radio base station 50 may also perform this monitoring. An example of operation in this case is shown below. When the cordless terminal 60 moves from zone A to zone B, for example, the wireless base station 50A detects a decrease in the reception level in zone A. When the wireless base station 50A detects this, it notifies the connected cordless subscriber circuit 16 of control information indicating a decrease in the reception level. When cordless subscriber circuit 16 receives this control information, it forwards it to cordless controller 18 via cordless control line 110. When the cordless controller 18 receives control information indicating a decrease in the reception level from the wireless base station 50, it instructs the wireless base stations 50 disposed around the wireless base station 50A to monitor the reception level. Each base station 50 that receives this monitoring instruction reports the monitoring result to the cordless controller 18. The cordless controller 18 selects the wireless base station 50B with the highest reception level among the reported ones.
is determined to be the destination zone B, and the communication channel switching process is performed by controlling the cordless switch 20.

In either case, according to the present embodiment, the time division switch 30 and the central processing module 40 do not need to be involved in the communication channel switching process within the line trunk module 10. Therefore, it is possible to quickly respond to the frequent switching of channels during communication, which is unique to mobile communication.

In the embodiment shown in FIG. 1, the highway interface controller 22 and the cordless controller 18 are configured separately, but they may be configured as the same controller 74 as shown in FIG. In addition, at this time, in the case of the wired interface circuit 70 that does not require switching processing of the channel during a call, the call path of the cordless switch 72 is fixedly connected.

In this embodiment, the switching system capable of accommodating wireless subscriber terminals according to the present invention is applied to a digital private branch exchange, but the present invention is not limited to this, and can be used, for example, for key telephones and central offices. It is also applicable to switching systems such as exchanges or collective telephone exchanges (CES). If the present invention is applied to a central office exchange,
The zone configuration may be configured in consideration of the movement range of the mobile communication terminal. Furthermore, in this embodiment, a cordless telephone is used as an example of the wireless mobile terminal, but it may also be a portable data terminal, for example.

[0026]

As described above, according to the switching system capable of accommodating wireless subscriber terminals of the present invention, the line interface housing section (front end) of the switching device mainly performs mobility management of the mobile communication terminals to be controlled. Since the communication channel is switched without going through the main switch of the switching device main body, the processing load on the central processing unit of the switching device that controls the main switch can be significantly reduced. Therefore, without significantly improving the processing capacity of the exchange equipment or making major changes to the software of the exchange equipment itself, various wired services such as multi-function telephone accommodation and ISDN compatible functions can be inherited. In addition, it is possible to accommodate wireless communication terminals such as cordless telephone terminals that are compatible with mobile communication in a micro zone configuration. Furthermore, with the present invention, the line interface accommodating section of the switching device can accommodate a mixture of wired interface circuits and cordless subscriber circuits, flexibly responding to various mixed accommodating needs expected to be required in offices, etc. can.

[Brief explanation of drawings]

FIG. 1 is a functional block diagram showing an embodiment in which a switching system capable of accommodating wireless subscriber terminals according to the present invention is applied to a private branch exchange;

FIG. 2 is a system configuration diagram showing an embodiment in which a switching system capable of accommodating wireless subscriber terminals according to the present invention is applied to a private branch exchange;

FIG. 3 is a wiring diagram showing the backboard wiring of the line trunk module in the embodiment shown in FIG. 1;

[Figure 4]
FIG. 3 is a functional block diagram showing another embodiment in which the switching system capable of accommodating wireless subscriber terminals according to the present invention is applied to a private branch exchange.

[Explanation of symbols]

10-1 to 10-n Line trunk module 12-1 to 12-n Universal slot 14
-1 to 14-n Wired interface circuit 16-
1 to 16-n cordless subscriber circuit 18
Cordless controller 20 Cordless switch 22
highway interface controller

Claims (4)

[Claims] Claim 1: A wireless subscriber terminal capable of accommodating a plurality of wired and wireless subscriber terminals and performing switching control associated with call connection between the subscriber terminals by main call control means and main switch means. a wireless subscriber terminal interface means for accommodating a wireless base station for wirelessly communicating with the wireless subscriber terminals in a zone; mobile control switch means connected to the wireless subscriber terminal interface means for controlling switching of the wireless subscriber terminal interface means according to a switching instruction; A wireless device characterized by having a call control device for controlling movement, which instructs the switching device for controlling movement to switch when moving between zones, and enables communication accompanying the movement between the wireless base stations. An exchange system that can accommodate subscriber terminals. 2. The switching system according to claim 1, wherein the wireless subscriber terminal interface means is mounted in a general-purpose slot together with a wired interface circuit, and is connected to the main switch means via the movement control switch means. , A switching system capable of accommodating wireless subscriber terminals, characterized in that the switching system is connected to the main call control means via the mobile control call control means. 3. The switching system according to claim 2, wherein the movement control switch means, the movement control call control means, and a plurality of general-purpose slots are housed in a line interface accommodation means, and the line interface accommodation means accommodates the plurality of line interfaces. 1. A switching system capable of accommodating wireless subscriber terminals, characterized in that call control and call connection are performed by connecting the means to main switch means and main call control means, respectively. 4. A wireless subscriber terminal that accommodates a plurality of wired and wireless subscriber terminals and performs switching control associated with call connections between the subscriber terminals using a main call control means and a main switch means. In the switching system, the switching system includes a wired interface means and a wireless system that accommodates a wireless base station that communicates wirelessly with the wireless subscriber terminal in the zone and interfaces with the wireless subscriber terminal. a general-purpose slot in which any one of the interface means is mounted, and a movement control for controlling switching of the wireless subscriber terminal interface means according to a switching instruction when the wireless subscriber terminal interface means is mounted in the general-purpose slot. The switch means relays and distributes wired and wireless call control information between the interface means mounted in the general-purpose slot and the main call control means. and call control means for controlling movement, which instructs the switching means for movement control to switch when the wireless base station moves between zones, and enables communication accompanying movement between the wireless base stations. An exchange system capable of accommodating wireless subscriber terminals characterized by: