JP2001313586A - Wireless link and its system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wireless link and its system that can switch incoming and outgoing signal lines with a simple configuration. SOLUTION: In the wireless link method that conducts 2-way communication with a time division duplex system where an incoming/outgoing signal is alternately transmitted, a power level of a signal line 2 connected to a wireless unit 1 is monitored, a signal line 3 used to transmit an incoming signal to the wireless unit 1 or the signal line 2 used to transmit an outgoing signal from the wireless unit 1 are selected and connected to an antenna 6 depending on the power level.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radio link method and a system thereof for performing bidirectional communication by a time division duplex system, and more particularly to a radio link method and a system thereof capable of switching between upper and lower signal lines with a simple configuration. It is about.

[0002]

2. Description of the Related Art Conventionally, a radio link method for performing bidirectional communication by a time division duplex system in which uplink and downlink signals are transmitted alternately includes a radio 1 for generating a radio signal (an electric signal for wireless transmission). A downlink signal line 2 for transmitting the generated radio signal (downlink signal), an uplink signal line 3 for transmitting the uplink signal, and a switch 4 for switching between the downlink and uplink signal lines 2 and 3; Control signal line 21 for transmitting a control signal for line switching from wireless device 1 to switch 4
And an antenna 6 for actually transmitting and receiving a radio signal (radio wave) to and from the terminal 5.

The radio 1 generates a radio signal (down signal) to be transmitted to the terminal 5 and sends it to the down signal line 2, and a radio signal (up signal) input from the terminal 5 to the antenna 6. From the upstream signal line 3 for receiving and processing, and a function for controlling line switching by the switch 4.

The switch 4 has a function of connecting one of the signal lines 2 and 3 to an antenna by opening and closing the downstream signal line 2 and the upstream signal line 3 in response to a control signal from the wireless device 1. .

[0005]

In the conventional radio link method, a control signal for controlling a switch is transmitted from the radio 1 separately from a radio signal for transmission to the terminal 5. Therefore, it is necessary to secure the function of the wireless device 1 for transmitting the control signal and the physical or logical link for transmitting the control signal, which has led to the complexity and high cost of the wireless link system.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems and to provide a radio link method and a system thereof capable of switching between upper and lower signal lines with a simple configuration.

[0007]

SUMMARY OF THE INVENTION In order to achieve the above object, a method of the present invention is a wireless link method for performing two-way communication by a time division duplex system in which uplink and downlink signals are transmitted alternately. Monitoring the power level of a connected signal line, and connecting to an antenna by switching between a signal line for transmitting an uplink signal to the radio and a signal line for transmitting a downlink signal from the radio according to the power level. It is.

In addition, the device of the present invention monitors the power level of a signal line connected to a radio in a radio link system for performing bidirectional communication by a time division duplex system in which uplink and downlink signals are transmitted alternately. Signal line monitoring means, and upper and lower signal line switching means for switching between a signal line for transmitting an upstream signal to the wireless device and a signal line for transmitting a downstream signal from the wireless device and connecting to an antenna according to the power level. It is provided.

An optical transmission system for converting a signal of the line into an optical signal and transmitting the signal through an optical fiber may be inserted into the signal line.

[0010]

An embodiment of the present invention will be described below in detail with reference to the accompanying drawings.

As shown in FIG. 1, the radio link system according to the present invention transmits a radio signal 1 for generating a radio signal (electric signal for wireless transmission) and a generated radio signal (downlink signal). A downstream signal line 2; an upstream signal line 3 for transmitting upstream signals; a switch 4 for switching between the downstream and upstream signal lines 2 and 3;
A detector 7 for detecting whether or not a downlink signal is being transmitted by monitoring the power level of the signal and providing a control signal to the switch 4; and an antenna for actually transmitting and receiving a radio signal (radio wave) between the terminal 5 6.

The wireless device 1 generates a wireless signal (downlink signal) to be transmitted to the terminal 5 and sends it to the downlink signal line 2, and a wireless signal (uplink signal) from the terminal 5 to the antenna 6. From the upstream signal line 3 to perform reception processing.

The detector 7 constitutes signal line monitoring means for monitoring the power level of the downstream signal line 2, and includes a switch 4.
Constitutes up / down signal line switching means for switching the down / up signal lines 2 and 3 to connect to the antenna 6 according to the power level.

The switching operation of the signal line according to the present invention will be described below.

In the radio link method for performing two-way communication by the time division duplex method, the downlink is transmitted while the signal is being transmitted from the wireless device 1 to the downlink signal line 2 and while the signal is not being transmitted. The power levels of the signal lines 2 are different.

The detector 7 constantly monitors the power level of the downstream signal line 2, and when the power level of the downstream signal line 2 exceeds a predetermined power level, the radio 1 Is transmitted, and a control signal is transmitted to the switch 4 so that the contact of the switch 4 on the down signal line 2 side is closed and the contact of the up signal line 3 side is opened. If the power level of the downstream signal line 2 does not exceed a predetermined power level, control is performed so that the downstream signal line 2 side contact is opened and the upstream signal line 3 side contact is closed.

As described above, the radio link system of FIG. 1 can switch between the downlink signal line 2 and the uplink signal line 3 by monitoring the power level of the signal line. Therefore, it is not necessary to secure the function of the wireless device 1 for transmitting the control signal for switching the upper and lower signal lines and the physical or logical link. Thereby, the wireless link system can be simplified and the cost can be reduced as compared with the related art.

The wireless link method according to the present invention is particularly effective for a system in which it is difficult to send a control signal from the wireless device 1 to the switch 4 for opening and closing a signal line. As an example, the application system of FIG. 2 will be described.

As shown in FIG. 2, the radio link system according to the present invention comprises a radio 1 for generating a radio signal (electrical signal for radio transmission) and an optical signal from the radio 1 Down-converting E / O converter 11, an optical fiber 13 for transmitting the optical signal, and a down-converting optical signal converted by down-converting E / O converter 11 into an original radio signal. An O / E converter 14, an amplifier 16 for amplifying the wireless signal, a downstream signal line 2 for transmitting the wireless signal (down signal), an upstream signal line 3 for transmitting the upstream signal, A switch 4 for switching between the upstream signal lines 2 and 3 and a detection for monitoring the power level of the downstream signal line 2 to detect whether a downstream signal is being transmitted and to provide the switch 4 with a control signal. Vessel 7,
An antenna 6 for actually transmitting and receiving a radio signal (radio wave) to and from the terminal 5, an amplifier 16 for amplifying a radio signal (uplink signal) from the uplink signal line 3, and an uplink for converting the radio signal to an optical signal E / O converter 12, optical fiber 13 for transmitting the optical signal, and upstream O / E conversion for reversely converting the optical signal converted by upstream E / O converter 12 into the original wireless signal And a vessel 15.

The wireless device 1 has a function of generating a wireless signal (down signal) to be transmitted to the terminal 5 and transmitting it to the down signal line 2, and a function of transmitting a wireless signal (up signal) from the terminal 5 to the antenna 6. From the upstream signal line 3 to perform reception processing.

The detector 7 constitutes signal line monitoring means for monitoring the power level of the downlink signal line 2, and the switch 4
Constitutes up / down signal line switching means for switching the down / up signal lines 2 and 3 to connect to the antenna 6 according to the power level.

In this radio link system, an optical transmission system is inserted in a signal line. The switching operation of the signal line is as described above. In the related art, in order to send a control signal from the wireless device 1 to the switch 4, it is necessary to separately provide an E / O converter, an optical fiber, and an O / E converter, which leads to a complicated system and high cost. . According to the present invention, since an optical transmission system for a control signal becomes unnecessary, a wireless link system can be simplified and cost can be reduced.

[0023]

The present invention exhibits the following excellent effects.

(1) It is not necessary to secure a function of the radio 1 for transmitting a control signal for switching the upper and lower signal lines and a physical or logical link, and the time division duplex system has a simple configuration. A wireless link for bidirectional communication can be established.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a wireless link system according to an embodiment of the present invention.

FIG. 2 is a configuration diagram of a wireless link system which is one application system of the present invention.

FIG. 3 is a configuration diagram of a conventional wireless link system.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Radio 2 Downlink signal line 3 Uplink signal line 4 Switch (up / down signal line switching means) 6 Antenna 7 Detector (signal line monitoring means) 11 Downlink E / O converter 12 Uplink E / O converter 13 Optical fiber 14 O / E converter for downstream 15 O / E converter for upstream

 ────────────────────────────────────────────────── ─── Continued on the front page F term (reference) 5K002 AA01 AA03 DA04 DA05 FA01 5K011 DA21 FA01 GA04 KA00 KA02 LA00 LA01 5K018 AA04 BA03 CA01 FA01 FA05 HA01 5K067 AA42 BB01 BB21 CC04 EE02 EE10 HH22 LL01

Claims (3)

[Claims] In a wireless link method for performing bidirectional communication by a time division duplex method in which uplink and downlink signals are transmitted alternately, a power level of a signal line connected to a wireless device is monitored, and the power level is monitored according to the power level. And a signal line for transmitting an uplink signal to the radio device and a signal line for transmitting a downlink signal from the radio device, and connecting the signal line to an antenna. 2. A signal line monitoring means for monitoring a power level of a signal line connected to a wireless device in a wireless link system for performing bidirectional communication by a time division duplex system for alternately transmitting uplink and downlink signals, Depending on this power level,
A radio link system, comprising: a radio line switching means for switching between a signal line for transmitting an uplink signal and a signal line for transmitting a downlink signal from the radio device to connect to an antenna. 3. The wireless link system according to claim 2, wherein an optical transmission system for converting a signal of the line into an optical signal and transmitting the signal through an optical fiber is inserted into the signal line.