JPH09200144A - Optical amplifier and relay system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the optical amplifier and relay system in which a repeater output level is suppressed low and a long relay interval is realized by arranging an Er added fiber to an optical transmission line between repeaters so as to amplify an optical data signal on the way of the transmission line. SOLUTION: The repeater 1 is made up of an optical amplifier 3, a remote stimulation light source 4, and an optical multiplexer/demultiplexer 5 and an Er added fiber 6 is arranged to an optical transmission line 2. A stimulated light emitted from the stimulation light source 4 in the repeater is multiplexed main signal group and an optical data signal in the Er added fiber 6 of the optical transmission line is amplified. Furthermore, the repeater 1 consists of the 2-way optical amplifier 3, the optical multiplexer/demultiplexer 5, the stimulated light source 4 and a loopback section 8 used for a monitor function and the Er added fiber 6 is arranged on the way of the optical transmission line 2 consisting of optical fibers. The optical data signal is amplified and propagated by the optical amplifier 3 and the Er added fiber 6 on the way of the optical transmission line alternately.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a repeater transmission system, and more particularly to an optical amplification repeater system using an optical amplifier.

[0002]

2. Description of the Related Art Conventionally, as an optical amplification repeater system, a plurality of optical amplification repeaters are arranged at regular intervals in an optical transmission line to repeat amplification of an optical data signal to realize long-distance transmission. It was FIG. 5 is a configuration diagram of a conventional optical amplification repeater system and a relationship diagram of signal light power thereof. The signal light power decreases at a constant rate in the optical transmission line, and the pattern of collective amplification in the optical amplification repeater is repeated.

[0003]

The repeater interval is mainly determined by the transmission rate, repeater output, S / N, transmission line loss, and dispersion value of the transmission line fiber. It is most effective to increase the output. However, when the output of the optical signal is increased, a non-linear phenomenon occurs in the transmission line and the quality of the optical data signal deteriorates.
There was a restriction on the output level of each optical amplification repeater. A further drawback of increasing the output of the optical amplification repeater is the problem of reliability of the semiconductor laser in the amplifier.
The repeater output and the reliability of the semiconductor laser are generally inversely proportional to each other, and the reliability of the semiconductor laser decreases as the repeater output increases.

An object of the present invention is to provide an optical amplification repeater system which can suppress the output level of a repeater device and realize a long repeat interval.

[0005]

According to the present invention, an optical amplifier for amplifying an optical data signal, a pumping light source, and an optical multiplexer / demultiplexer are used in a repeater transmission system in which attenuation and amplification of an optical data signal are repeated for propagation. A relay device including a container,
By providing an Er-doped optical fiber in the optical transmission path between the repeaters, the optical amplification signal is obtained by alternately amplifying and propagating the optical data signal in the repeater and the optical transmission path. To be

Further, according to the present invention, in a repeater transmission system which repeats attenuation and amplification of an optical data signal for propagation, it is constituted by an optical amplifier for amplifying the optical data signal, a pumping light source and an optical multiplexer / demultiplexer. And a remote pumping amplifier configured to have Er-doped fibers bidirectionally in each of the optical transmission lines between the relaying devices so that the optical data signal is transmitted to the relaying device and the remote pumping amplifier. An optical amplification repeater system is obtained which is characterized by alternately amplifying and propagating.

Further, according to the present invention, in the repeater transmission system for repeating the attenuation and amplification of the optical data signal for propagation, the optical amplifier for amplifying the optical data signal, the pumping light source and the optical multiplexer / demultiplexer are used. And the optical transmission line itself between each relay device is composed of a low-doped fiber,
An optical amplification repeater system is obtained in which the optical data signal is alternately amplified and propagated in the repeater and the optical transmission line.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing the relationship between the configuration of the optical amplification relay system of the present invention and the signal light power. The repeater 1 is composed of an optical amplifier 3 having a function equivalent to that of a conventional optical amplification repeater, a pumping light source 4 for remote pumping, and an optical multiplexer / demultiplexer 5, and an Er-doped fiber 6 is arranged in the optical transmission line 2. doing. It becomes possible to combine the pumping light emitted from the pumping light source in the repeater with the main signal system and amplify the optical data signal in the Er-doped fiber portion in the optical transmission path.

FIG. 2 is a block diagram showing an embodiment of the present invention. The repeater 1 is composed of a bidirectional optical amplifier 3, an optical multiplexer / demultiplexer 5, an excitation light source 4, and a loopback unit 8 used as a monitoring function. Further, the Er-doped fiber 6 is arranged in the middle of each optical transmission line 2 formed by the optical fiber. The pumping light emitted from the pumping light source 4 of the repeater 1 is combined with the main signal system by the optical multiplexer / demultiplexer 5 and is backward-pumped by the Er-doped fiber unit 6, so that the optical amplifier 3 and the optical transmission line It propagates while alternately amplifying with the Er-doped fiber 6.

FIG. 3 is a block diagram showing another embodiment of the present invention. The repeater 1 is composed of the optical amplifier 3, the optical multiplexer / demultiplexer 5, the pumping light source 4, and the loopback unit 8 as in FIG. The remote excitation amplifier 9 is composed of bidirectional Er-doped fibers. The repeater 1 and the remote pumping amplifier 9 are alternately arranged in the optical transmission line 2, and the pumping light source 4 in the repeater emits pumping light to amplify the optical data signal by the remote pumping amplifier 9.

FIG. 4 is a block diagram showing still another embodiment of the present invention. As in FIGS. 2 and 3, the repeater 1 includes an optical amplifier 3, an optical multiplexer / demultiplexer 5, a pumping light source 4, and a loopback unit 8. The transmission path itself between each relay device is E
In this method, r is composed of a lightly doped fiber 10 to propagate an optical data signal.

[0012]

As described above, according to the present invention, by arranging the Er-doped fiber in the optical transmission line between the repeaters, it becomes possible to amplify the optical data signal in the middle of the transmission line, and to repeat the long repeater. Intervals can be realized. Also,
If the repeater interval is the same as the conventional one, it is possible to reduce the output level of the repeater, suppress the deterioration of the quality of the optical data signal due to the nonlinear phenomenon in the transmission line, and improve the reliability of the amplifier in the repeater. Has the effect of increasing the.

[Brief description of drawings]

FIG. 1A is a configuration diagram of an optical amplification repeater system of the present invention, and FIG. 1B is a relationship diagram of signal light power in FIG.

FIG. 2 is a configuration diagram showing an embodiment of the present invention.

FIG. 3 is a configuration diagram showing another embodiment of the present invention.

FIG. 4 is a configuration diagram showing still another embodiment of the present invention.

5A is a configuration diagram of a conventional optical amplification repeater system, and FIG. 5B is a relationship diagram of signal light power in FIG. 5A.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Repeater 2 Optical transmission line 3 Optical amplifier 4 Excitation light source 5 Optical multiplexer / demultiplexer 6 Er-doped fiber 7 Optical amplification repeater 8 Loopback unit 9 Remote excitation amplifier 10 Er-doped fiber

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Claims (3)

[Claims] 1. A repeater transmission system that repeats attenuation and amplification of an optical data signal for propagation, and a repeater comprising an optical amplifier for amplifying the optical data signal, a pumping light source, and an optical multiplexer / demultiplexer. An optical amplification repeater system, wherein the optical data signal is alternately amplified by the repeater and the optical transmission line and propagated by providing an Er-doped optical fiber in the optical transmission line between the repeaters. 2. A repeater transmission system that repeats attenuation and amplification of an optical data signal for propagation, and a repeater comprising an optical amplifier for amplifying the optical data signal, a pumping light source, and an optical multiplexer / demultiplexer. By providing the remote pumping amplifier configured with Er-doped fibers bidirectionally in the optical transmission line between the repeaters, the optical data signal is alternately amplified by the repeater and the remote pumping amplifier. Optical amplification repeater system characterized by propagation. 3. A repeater transmission system that repeats attenuation and amplification of an optical data signal for propagation, and a repeater comprising an optical amplifier for amplifying the optical data signal, a pumping light source, and an optical multiplexer / demultiplexer. An optical amplification repeater system characterized in that the optical transmission line itself between the repeaters is composed of a low-doped fiber, and the optical data signal is alternately amplified and propagated in the repeater and the optical transmission line.