JPH06132896A - Optical output monitor circuit - Google Patents

Abstract

PURPOSE:To prevent an optical output alarm signal from being outputted at the time of no signal by inhibiting an output alarm in the state of no signal of a burst signal. CONSTITUTION:A transmitting signal generation part 1 is controlled timing for outputting transmitting data 101 by a control signal 103 from a timing control part 5 for sending the burst signal. The transmitting data 101 are converted to optical signals 107 and 108 and outputted by driving a laser diode 3 with a laser diode driving part 2. The optical signal 107 is monitored by a PIN diode 7 for monitoring light output and when the abnormality of the optical output is detected by an optical output abnormality detection part 4, an optical output alarm signal 105 is outputted. An AND circuit 6 sends an optical alarm output 106 corresponding to the AND of the optical output alarm signal 105 and the control signal 103 and inhibits the output at the time of no signal of a burst signal by ANDing the optical output alarm signal 105 and the control signal 103 from the timing control part 5, and the optical output alarm signal 105 is prevented from being outputted at the time of no signal.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical output monitoring circuit,
In particular, the present invention relates to an optical output monitoring circuit that issues an alarm when the output level of signal light drops during optical burst signal transmission.

[0002]

2. Description of the Related Art In a conventional optical output monitoring circuit, in the case of burst signal transmission by an optical transmission device, an optical output alarm is issued when the optical output is stopped when there is no burst signal.

A ping-pong transmission system, which is an application example of optical burst signal transmission, will be described with reference to FIG. The optical transmission device 21 and the optical transmission device 22 are composed of one optical fiber 23 connecting them. One-core optical fiber 23
Burst signals are transmitted and received alternately in a time-division transmission system. FIG. 3 shows a change in data on the optical axis on the optical fiber, A is a burst signal from the optical transmission device 21 to the optical transmission device 22, and B is a burst signal from the optical transmission device 22 to the optical transmission device 21. It is a signal.

[0004]

In this conventional optical output monitoring circuit, in the optical burst signal transmission by the optical transmission device, the optical output is stopped when there is no signal in the burst signal. There was a problem that an output alarm was output.

[0005]

SUMMARY OF THE INVENTION An optical output monitoring circuit of the present invention comprises a transmission signal generator for outputting transmission data at the timing of a control signal, and a laser diode and a laser diode for converting the transmission data into an optical signal and outputting the optical signal. A drive unit, a PIN diode for monitoring that monitors the optical signal and outputs it as an optical output signal, an optical output abnormality detection unit that outputs an optical output alarm signal when an abnormality of the optical output signal is detected, and a burst signal A burst signal sending timing control section for outputting the control signal for controlling the sending of the signal, and a logical product circuit for sending an optical alarm output by a logical product of the control signal and the optical output alarm signal.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of the present invention.

In this embodiment, the transmission signal generator 1 for outputting the transmission data 101 at the timing of the control signal 103.
And a laser diode 3 and a laser diode drive unit 2 that convert the transmission data 101 into an optical signal 107 and output the optical signal 107.
The optical output signal 10 (108) by monitoring the optical signal 107 (108).
4 for monitoring PIN diode 7 and optical output alarm signal 10 when an abnormality of the output signal 104 is detected.
5, an optical output abnormality detection unit 4 that outputs 5, a burst signal transmission timing control unit 5 that outputs a control signal 103 that controls the transmission of a burst signal, and a logical product of the control signal 103 and the optical output alarm signal 105. The logical product circuit 6 for sending out the alarm output 106.

Next, the operation of this embodiment will be described. The transmission signal generator 1 controls the output timing of the transmission data 101 by the control signal 103 from the burst signal transmission timing controller 5. The transmission data 101 is converted into an optical signal 107 by the laser diode driving section 2 driving the laser diode 3. The optical signal 107 is monitored by the optical output monitoring PIN diode 7, and when the optical output abnormality detecting unit 4 detects an abnormality in the optical output, it outputs the optical output alarm signal 105. In a burst signal,
The optical output warning signal 105 output when there is no signal and the control signal 103 from the burst signal transmission timing control unit 5 are logically ANDed to inhibit the output of the optical output warning signal 105 when there is no signal. .

[0009]

As described above, according to the present invention, in the optical burst signal transmission by the optical transmission device, by inviting the optical output warning without a burst signal, the optical output warning signal when there is no signal can be generated. It has the effect of preventing emission.

[Brief description of drawings]

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

FIG. 2 is a block diagram for explaining an example of a conventional optical output monitoring circuit.

FIG. 3 is a diagram for explaining ping-pong transmission of optical burst signal transmission.

[Explanation of symbols]

 1 Transmitting Signal Generation Section 2 Laser Diode Driving Section 3 Laser Diode 4 Optical Output or Higher Detection Section 5 Timing Control Section 6 Logical Product Circuit 7 PIN Diode

Claims (1)

[Claims] 1. A transmission signal generator for outputting transmission data according to the timing of a control signal, a laser diode and a laser diode driver for converting the transmission data into an optical signal and outputting the optical signal, and an optical output for monitoring the optical signal. A PIN diode for monitoring that outputs as a signal, an optical output abnormality detection unit that outputs an optical output alarm signal when an abnormality of the optical output signal is detected, and a burst that outputs the control signal for controlling the transmission of a burst signal. An optical output monitoring circuit, comprising: a signal transmission timing control unit; and a logical product circuit for transmitting an optical alarm output by a logical product of the control signal and the optical output alarm signal.