JPH0937340A - Time-division double terminal control system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the price of connected transmission lines between a control station in TDMA/TDD mobile communication such as PHS and plural terminal base stations conneced to the control station. SOLUTION: Single direction transmitting optical fibers 25, 26 are prepared as transmission lines between a terminal base station 60 and a control station 70. Switches 21, 23, 28, 30 are connected like solid lines in a TDMA transmitting frame and switched like dotted lines in a receiving frame. A control signal and a monitor signal are transferred by the counter transmission line of the transmission line of transmitting/receiving data time-dividedly transmitted alternately through the fibers 25, 26. Consequently the number of optical fibers can be reduced from conventional four fibers to two fibers.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a TDMA / TDD.
The present invention relates to a terminal control method in a (time division multiple access / time division duplex) communication system, and particularly to control / monitoring of a distributed base station connected to a control station added to a private branch exchange.

[0002]

2. Description of the Related Art Time division duplex communication (TDD)
n Duplex) system as an example, Personal Handy phone System (PHS)
There is. The PHS is a simple mobile phone system, which is a cordless phone system that enables outdoor calls. It is possible to add a control station to a private branch exchange (PBX), connect a plurality of terminal base stations to the control station, and disperse them to form a kind of wireless microcellular system, which can be used as a so-called system cordless telephone.

In this system cordless, PBX
When using an optical fiber to exchange data between the attached control station and terminal base station, the optical demultiplexer is expensive for bidirectional transmission with a single optical fiber, and moreover, the optical loss due to the demultiplexer is large. Due to many technical issues such as high cost, the line that sends traffic transmission data from the control station to the terminal base station and the line that sends traffic reception data from the terminal base station to the control station are installed separately. . Further, when the control station performs control / monitoring for maintenance of terminal base stations distributedly arranged, in addition to the two lines used for the traffic transmission, a line for transmitting control data from the control station to the terminal station, and a terminal Lines are provided for transmitting monitoring data such as the status of terminal stations from the station to the control station.

FIG. 3 is a block diagram of a conventional control station and terminal base station. In the figure, 40 is a terminal base station, 50 is a control station, 1 is a terminal base station traffic transmission data transmission unit (T
x), 2 is a terminal base station traffic transmission data receiving unit (Rx), 3 is a terminal base station control data receiving unit (CONT)
Receiving unit), 4 is a terminal base station monitoring data transmitting unit (MON transmitting unit), 5 is a control station traffic transmission data transmitting unit, 6
Is a control station traffic transmission data receiving unit, 7 is a control station control data transmitting unit (CONT transmitting unit), 8 is a control station monitoring data receiving unit (MON receiving unit), and 9, 11, 18 and 20 are optical-electric conversions. Section (O / E conversion section) 10, 12, 17,
Reference numeral 19 is an electric-optical conversion unit (E / O conversion unit), and 13 to 16 are optical fiber transmission lines. The transmitter 5 and receiver 6 of the control station 50 are connected to the private branch exchange, but are not shown.

The transmission data for traffic transmission output from the transmission section 5 of the control station 50 is converted into light by the E / O conversion section 17 and sent to the terminal base station 40 by the optical fiber 13, and the O / E conversion section 9 is transmitted. Is converted into an electric signal by the transmitter (T
x) 1 is transmitted to the mobile station. Radio waves from the mobile station are received by the receiving unit (Rx) 2 of the terminal base station 40, and E
The light is converted into light by the / O converter 10 and sent to the control station 50 by the optical fiber 14, converted into an electric signal by the O / E converter 18, and input to the receiver 6.

On the other hand, the control signal from the control station 50 to the terminal base station 40 is output from the CONT transmission section 7 and the E / O
The light is converted by the converter 19 and transmitted to the terminal base station 40 by the optical fiber 15, converted into an electric signal by the O / E converter 11, and input into the CONT receiver 3 to be input to the terminal base station 4
0 control is performed. The monitoring signal that detects the operation state of each unit of the terminal base station 40 is output from the MON transmission unit 4,
It is converted into light by the E / O converter 12, transmitted to the control station 50 via the optical cable 16, converted into an electric signal by the O / E converter 20, and input to the MON receiver 8.

[0007]

SUMMARY OF THE INVENTION In the above-mentioned conventional configuration,
A transmission line between the terminal base station 40 and the control station 50 is provided with one optical fiber 13 and 14 respectively for transmitting and receiving data for traffic transmission, and for controlling and monitoring the terminal base station 40. Since one optical fiber 15 and 16 is arranged and a total of four optical fibers are provided, there is a problem that equipment cost is required.

An object of the present invention is to provide a terminal control system in time division duplex communication which contributes to economic efficiency by reducing the laying amount of optical fiber, which has been a problem in the prior art.

[0009]

SUMMARY OF THE INVENTION The present invention provides a control station added to a private branch exchange in a time division multiple access / time division transmission / reception mobile communication system and traffic transmission / reception data connected to the control station by a transmission line. In a terminal control system in which a terminal base station for transmitting and receiving is arranged, and the control station controls the operation of the terminal base station and monitors the operating state, the transmission line transmits traffic transmission data from the control station to the terminal base station. And a second optical fiber for transmitting traffic reception data from the terminal base station to the control station. The control station switches between the traffic transmission data and the control data and outputs the first optical fiber. A switch, a first electro-optical converter that converts the output of the first switch into light and sends the light to the first optical fiber, and an input from the second optical fiber. The terminal base is provided with a first optical / electrical converter for converting into an air signal, and a second switcher for switching and outputting the output of the first optical / electrical converter into traffic reception data and monitoring data. The station outputs a second optical / electrical converter for converting an input from the first optical fiber into an electric signal, and an output of the second optical / electrical converter by switching between traffic transmission data and control data. A third switching device to
A fourth switching device for switching and outputting traffic reception data and monitoring data; and a second electrical / optical converter for converting the output of the fourth switching device into light and sending it to the second optical fiber. Wherein the first to fourth switching devices transmit the traffic transmission data from the control station to the terminal base station via the first optical fiber, while the monitoring data is transmitted during the transmission frame. A reception frame transmitted from the terminal base station to the control station via the second optical fiber and transmitting the traffic reception data from the terminal base station to the control station via the second optical fiber. During the period, the switching control is performed so that the control data is transmitted from the control station to the terminal base station via the first optical fiber, and the first and second optical fibers are unidirectional transmission lines, respectively. Becomes It is characterized in that it has been configured Uni.

[0010]

FIG. 1 is a block diagram showing an embodiment of the present invention. In the figure, 60 is a terminal base station, and 70 is a control station. Reference numerals 1 to 8 are attached to the same parts as those of the conventional configuration example shown in FIG. 22 and 29 are optical-electrical converters (O /
E conversion unit), 24 and 27 are electric-optical conversion units (E / O conversion units), and 25 and 26 are optical fiber transmission lines 21, 23, 2
8 and 30 are switching devices. The transmitter 5 of the control station 70
Although the receiving unit 6 is connected to the private branch exchange, the illustration is omitted.

The operation of the embodiment of the present invention shown in FIG. 1 will be described. FIG. 2 is a time chart showing an example of the operation of the present invention. The number of optical fibers that used to be four in the past was changed to two,
One optical fiber 25 is connected from the control station 70 to the terminal base station 60.
The traffic transmission data (a) output from the transmission unit 5 and the control data (c) output from the CON transmission unit 7 are switched by the switch 28, and the E / O
The light converted by the conversion unit 27 is transmitted by the optical fiber 25. The switch 21 is switched corresponding to the switch 28. The other optical fiber 26 is used as a unidirectional transmission path from the terminal base station 60 to the control station 70, and the traffic reception data (b) received by the receiving unit 2 and the monitoring data output from the MON transmitting unit 4 are used. (D) is switched by the switch 23, and the light converted by the E / O converter 24 is converted into the optical fiber 26.
To transmit by. The switch 30 is switched corresponding to the switch 23.

As shown in FIG. 2, 4ch TDMA / T
Data for traffic transmission of the DD system is transmitted by alternately transmitting and receiving one slot in each frame composed of four slots. For example, transmission / reception is performed in a time division manner in the transmission slot T _x1 and the reception slot R _x1 . That is, during the frame in which the transmission data (a) is sent from the control station 70 to the terminal base station 60 via the optical fiber 25, all of the slots T _{x1 to} T _x4 of the frame or any one of the slots is set. From the terminal base station 60 to the optical fiber 26
The monitoring data (d) is sent to the control station 70 via. During this period, the switches 21, 23, 28 and 30 are connected as shown by the solid lines. In the next frame, switches 21, 23, 2
8 and 30 are switched as shown by a broken line, and during a frame in which the received data (b) is sent to the control station 70 via the optical fiber 26, all or all of the slots R _{x1 to} R _x4 of the frame are The control data (c) is sent to the terminal base station 60 via the optical fiber 25 using any one of the slots.

As described above, according to the present invention, since the two optical fibers 25 and 26 are both arranged as a unidirectional transmission line, the optical components when one optical fiber is used for bidirectional transmission. Technical problems due to wave filters are avoided.

[0014]

As described in detail above, by carrying out the present invention, only four optical fibers are required to be installed, four for each terminal base station, which is extremely economically advantageous.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of the present invention.

FIG. 2 is a time chart showing an example of the operation of the present invention.

FIG. 3 is a diagram showing a configuration example of a conventional TDD control station and terminal base station.

[Explanation of symbols]

 1 terminal base station traffic transmission data transmission unit 2 terminal base station traffic transmission data reception unit 3 terminal base station control data reception unit 4 terminal base station monitoring data transmission unit 5 control station traffic transmission data transmission unit 6 control station traffic transmission Data reception unit 7 Control station control data transmission unit 8 Control station control data reception unit 9, 11, 18, 20 O / E conversion unit 10, 12, 17, 19 E / O conversion unit 13 to 16 Optical fiber transmission line 22 , 29 O / E converter 24, 27 E / O converter 25, 26 Optical fiber transmission line 21, 23, 28, 30 Switching device 40, 60 Terminal base station 50, 70 Control station

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location H04Q 7/26 7/30 11/04

Claims (1)

[Claims] 1. A control station added to a private branch exchange in a time division multiple access / time division transmission / reception mobile communication system, and a terminal base station connected to the control station by a transmission line to transmit / receive traffic transmission / reception data. In the terminal control method in which the control station controls the operation of the terminal base station and monitors the operating state, the transmission line includes a first optical fiber that transmits traffic transmission data from the control station to the terminal base station, A second optical fiber for transmitting traffic reception data from the terminal base station to the control station, wherein the control station includes a first switching device for switching and outputting the traffic transmission data and the control data, and the first switching device. A first electro-optical converter that converts the output of the switching device into light and sends it to the first optical fiber, and a first electro-optical converter that converts the input from the second optical fiber into an electric signal. / Electrical converter and a second switcher for switching and outputting the output of the first optical / electrical converter between traffic reception data and monitoring data, and the terminal base station includes the first optical fiber. Second optical / electrical converter for converting an input from the optical signal into an electric signal, a third switcher for switching and outputting the output of the second optical / electrical converter between traffic transmission data and control data, and a traffic. A fourth switch for switching and outputting the received data and the monitoring data; and a second electric / optical converter for converting the output of the fourth switch into light and sending it to the second optical fiber. Wherein the first to fourth switching devices transmit the traffic transmission data from the control station to the terminal base station via the first optical fiber during a transmission frame, and the monitoring data is transmitted during the transmission frame. From the terminal base station to the second optical fiber Is transmitted to the control station via the second base station, and the control data is transmitted from the terminal base station to the control station via the second optical fiber. Switching control is performed so as to be transmitted to the terminal base station via the first optical fiber,
A time division duplex terminal control system characterized in that the first and second optical fibers are each configured to be a unidirectional transmission line.