JPH09191483A - Radio type private branch of exchange - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the need for line installation at the installation of the private branch of exchange by acting each extension terminal like a PHS (personal handiphone station) terminal and using a PHS terminal trunk for interface control with a public network. SOLUTION: A PHS terminal trunk 12 of a radio PBX 1 (private branch exchange) corresponding to an incoming call number detects a trunk line incoming call signal from a PHS radio base station (CS). The detected incoming call is given to an automatic reply transfer trunk 13 and a reply signal and a talkie tone are sent to a caller as a called party reply. Upon the receipt of a PBX extension number from the caller, the call is connected to a specific extension terminal 15 in response to the extension number switch-connected by a switch section 10. In the case of an external line dial request from an optional extension terminal 15, a dial call is sent from an idle PHS terminal trunk 12 to the CS2. Since the interface part with a public network and a mobile communication network utilizes an existing radio channel, a problem of line installation is avoided.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a private branch exchange (private exchange).
ate branch exchange: PBX)
The present invention relates to a wireless private branch exchange having an interface function with a mobile communication network.

[0002]

2. Description of the Related Art A PBX is an exchange for making switching connections between extension terminals within a premises and between extension terminals and subscriber terminals of a public network. Generally, an extension circuit for accommodating extension terminals,
PSTN (Public Swichd Telephone Network) and IS
It is composed of a trunk section that serves as an interface of a public network such as DN, a switch section that switches connection between the extension circuit and the trunk section, and a control device that controls them. In addition to wired terminals such as subscriber telephones, mobile networks such as car telephone systems, mobile telephone systems, and simple mobile telephone systems (personal handyphone systems: PHS) are also connected to the public networks. In addition, PHS
Connects a PHS connecting device to a public network, and further arranges a plurality of PHS radio base stations (cell stations: CS) in front of the PHS connecting device, and between PHS terminals and subscribing terminals via individual CSs. It provides personal communication (individual call).

[0003]

Generally, a plurality of extension terminals are connected to the PBX. Also, since the public network is connected to the switch section, wiring work in the trunk section is indispensable. Therefore, considering the line laying, it is impossible to arbitrarily change the installation location of the PBX once determined. In particular, when a PBX is installed in a depopulated area where there is no existing communication network to build a new communication network, there is a problem that the line laying cost increases significantly.

An object of the present invention is to provide a public network (PS) by cable.
It is an object of the present invention to provide a wireless PBX that eliminates the problem of line laying by utilizing the advantages of wireless public communication in the process of merging TN and ISDN) with a mobile communication network by wireless.

[0005]

In the wireless PBX provided by the present invention, an extension terminal in a premises is connected to a mobile communication network such as a PH.
The S terminal functions as a terminal group. In order to realize this function, a wireless terminal capable of mutual communication with a wireless base station connected to a public communication network, at least one trunk unit having interface means between this wireless terminal and an extension line, and the trunk Switch unit for selectively switching the extension telephone terminal connected to the trunk unit and an outgoing call from the extension terminal switched and connected by the switch unit from the trunk unit to the wireless base station, and the trunk unit receiving the call. And a control means for connecting the call to a designated extension terminal. When the trunk section is installed in an area where radio waves cannot reach, the wireless terminal and the interface means are separated from each other via a line.

The control means has, for example, an automatic response / transfer device for returning information prompting the caller to specify an extension number when a call is received at the trunk section, and the automatic response / transfer device receives the information due to the reply information. The extension terminal corresponding to the extension number is connected to the incoming call. Also, when there are a plurality of trunk units, the control means causes the call originated by the extension terminal to be sent from the trunk unit in an idle state to the radio base station.

[0007]

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is an overall configuration diagram of a public communication system including a wireless PBX of the present invention. Wireless PBX
1 is a PH via an existing PHS radio base station (CS) 2.
It is connected to the S connection device 4. Other CS2 and LS (local site) are connected to the PHS connection device 4,
This allows mutual connection with other PHS terminals 3 and public networks such as PSTN / ISDN. A public PBX 5 or public subscriber terminal 6 is connected to the public network via the LS.
Is connected.

The wireless PBX 1 of the present embodiment includes a switch unit 10 and a PB which are time division switches (TDSW).
PBX control unit 11 for controlling the operation of the entire X, public PHS
A PHS terminal trunk (P trunk) 12 having a terminal interface function, and an automatic response / transfer device (AA)
T) 13. A plurality of extension terminals 15 are connected to the switch section 10 via a line circuit (LC) 14.

The P trunk 12 has not only the function of the trunk portion (station line trunk (COT), ISDN trunk) of the conventional wired PBX, but also the interface function of the PHS terminal. The specific configuration of the P trunk 12 is as shown in FIG. 2, and includes a wireless unit A and a wired / wireless interface unit B.

The radio section A is composed of an antenna selector 121 for switching between transmitting and receiving antennas, and an RF unit 122 for converting high frequency / intermediate frequency based on the output of the synthesizer 123. Wireless / wired interface section B
Is a known π / 4 shift QPSK modem 124, (1 to
4) Channel codec 125, multiplexing / demultiplexing circuit 126, LAP-D control unit 127, trunk control unit 12
8 and an interface unit 129. LAP-
The D control unit 127 controls communication according to the ITU-T recommendation I430 standard, and the trunk control unit 12
8 analyzes the communication control information exchanged between the LAP-D control unit 127 and the PBX control unit 11.

In the P trunk 12 having such a structure, the received wave Rx from the antenna selector 121 is RF.
It is converted into an intermediate frequency signal RxIF by the unit 122 and Q
After being converted into a digital signal RxD by the PSK modem 124, it is demultiplexed (separated) by the multiplexing / demultiplexing circuit 126 via the channel codec 125. The control signal included in the demultiplexed signal is sent to the trunk control unit 128 via the LAP-D control unit 127. In the trunk control unit 128, the CPU analyzes the control signal based on the program in the ROM and the parameters in the RAM,
The result is sent to the PBX control unit 11 via the interface unit 129.

On the other hand, the control signal generated at the time of transmission is
From the PBX control unit 11 via the interface unit 129, the trunk control unit 128, the LAP-D control unit 127, the multiplexing / demultiplexing circuit 126, the channel codec 125,
It is sent to the wireless unit A via the QPSK modem 124.
It should be noted that each P trunk 12 is assigned a called number (subscriber number of a public PHS terminal) as in a normal PHS terminal.

Next, in the public communication system of FIG.
An operation example when a call is received to the wireless PBX 1 via the PHS connection device 4 and when an extension terminal 15 connected to the wireless PBX 1 makes a call to the public network will be described.

(Incoming connection from public network to extension terminal) CS
The incoming call number (public PHS
The P trunk 12 corresponding to the subscriber number of the terminal detects an incoming call. The detected incoming call is passed to the AAT 13. The AAT 13 automatically sends a response signal and a talky sound to the calling party as a called party response. The talky tone is a message for accepting an additional dial (extension number information) such as a PB signal from the calling party. PBX from the caller
When the extension number is received, the call (the P trunk 12 that received the call) is switched and connected to the specific extension terminal corresponding to the extension number. As a result, a call can be made between the caller and the extension terminal 15.

(Outgoing Connection from Extension Terminal to Public Network) A plurality of P's are issued in response to an outside call request from any extension terminal 15.
An empty P trunk 12 is captured from the trunks 12, and the captured P trunk 12 and the extension terminal 15 are connected. As a result, the same state as when a normal PHS terminal originates a call is formed.

The wireless PBX 1 of the present embodiment is CS
In the case where the P trunk 12 is installed in a portion where the radio wave from 2 does not reach directly, the P trunk 12 is separated into a wired / wireless interface section (B) 12a and a wireless section (A) 12b, and the wireless section 12b is provided as shown in FIG. Is preferably installed on a site within the coverage area of CS2, for example, on the roof of a building, and the wired / wireless interface unit 12a connected by a cable is installed on the premises.

As described above, the wireless PBX 1 of this embodiment
The individual extension terminals 15 function as a PHS terminal group that can be connected to the public network. Moreover, since the interface control with the public network is performed by the P trunk 12 equipped with the wireless terminal, the problem of line laying at the time of installation is eliminated. Therefore, temporary PBXs may be installed at various event venues,
Alternatively, it becomes possible to construct a communication network in a depopulated area or the like at low cost.

[0018]

As is clear from the above description, according to the wireless PBX of the present invention, the interface portion with the public network or the mobile communication network is realized by using the existing wireless line, and therefore the line is connected. There is no need to consider installation, and the conventional problems are solved.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a public communication system including a wireless PBX of the present invention.

FIG. 2 is a detailed configuration diagram of a trunk portion (P trunk) according to the present embodiment.

FIG. 3 is an explanatory diagram showing an example of an installation form of a wireless PBX.

[Explanation of symbols]

 1 wireless PBX 2 PHS wireless base station (CS) 3 other PHS terminal 4 PHS connection device 5 ordinary wired PBX 6 public subscriber terminal 10 switch unit 11 PBX control unit 12 PHS terminal trunk (P trunk) 13 automatic response / Transfer device 15 Extension terminal 121 on the premises 121 Antenna selector 122 RF unit 123 Synthesizer 124 QPSK modem 125 Channel codec 126 Multiplexing / demultiplexing circuit 127 LAP-D control unit 128 Trunk control unit 129 Interface unit

Claims (4)

[Claims] 1. A wireless terminal capable of mutual communication with a wireless base station connected to a public communication network, and at least one trunk section having interface means between the wireless terminal and an extension line, and the trunk section. A switch unit for selectively switching extension terminals connected to the extension circuit, and an outgoing call from the extension terminals switched and connected by the switch unit is sent from the trunk unit to the radio base station, and the trunk unit receives an incoming call. A wireless private branch exchange having control means for connecting the established call to a designated extension terminal. 2. The control means has an automatic response / transfer device that returns information prompting the caller to specify an extension number when a call is received at the trunk section, and is caused by the reply information. 2. The wireless private branch exchange according to claim 1, wherein an extension terminal corresponding to the extension number received by the user is connected to the incoming call. 3. The control means causes the call originated by the extension terminal to be sent from the trunk section in an empty state to the radio base station when there are a plurality of trunk sections. Wireless private branch exchange. 4. The wireless base station is a personal handyphone system (hereinafter, PHS) wireless base station,
4. The wireless private branch exchange according to claim 1, 2 or 3, wherein the wireless terminal is a PHS terminal according to the same communication protocol as the PHS wireless base station.