JPH04290020A - Multiplex optical communication system - Google Patents

Abstract

PURPOSE:To attain transmission with a small distortion even with a low modulation frequency by modulating and synthesizing plural electric signals into an optical signal of a different wavelength, sending it as one optical signal, decomposing and demodulating the signal after reception. CONSTITUTION:Plural electric signals SIG1-SIGn are modulated into optical signals of different wavelengths by optical modulator 111-11n of a transmitter 8 respectively and converted into one optical signal by an optical mixer 3 and sent through one optical fiber cable 4a and received by a receiver 9. A received optical signal is decomposed into optical signal with different wavelengths by a spectroscope 5 and demodulated into the original electric signals SIG1-SIGn by optical demodulators 171-17n respectively. Through the constitution without time division multiplex as above, the signal is sent with a small distortion even at a low modulation frequency.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical communication system, and more particularly to a multiplex optical communication system.

0002

2. Description of the Related Art Conventional multiplex optical communication systems generally employ a system in which a plurality of signals are multiplexed and transmitted in a time-division manner via a transmission line such as an optical fiber cable using a light source of one type of wavelength.

0003

[Problems to be Solved by the Invention] Conventional multiplex optical communication systems as described above use transmission paths in a time-division manner, so when transmitting analog signals, the modulation frequency must be raised to reduce distortion. There is a drawback that it must be done.

0004

[Means for Solving the Problems] The multiplex optical communication system of the present invention uses a plurality of optical signals that input one electrical signal among a plurality of different electrical signals, convert it into optical signals of mutually different wavelengths, and output the optical signals. a transmitting device comprising an optical modulator group having a modulator, and an optical mixer that inputs a plurality of optical signals of different wavelengths from the optical modulator group and outputs a single optical signal by combining them; Or one of the same type as the optical signal sent out from the transmitting device, which is a combination of multiple optical signals of different wavelengths.
A spectrometer that inputs an optical signal, divides it into multiple optical signals of different wavelengths, and outputs it; and an electrical signal that receives one of the multiple optical signals from the spectroscope. The receiver is equipped with an optical demodulator group having a plurality of optical demodulators for reproducing and outputting.

[0005]

Embodiments Next, embodiments of the present invention will be described with reference to the drawings.

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

In FIG. 1, an optical modulator group 1 includes optical modulators 11-1 that input electrical signals SIG1 to SIGn and convert them into optical signals having mutually different wavelengths λ1 to λn.
~11-n. Optical modulators 11-1 to 11-n
The optical signal from λ1 is inputted to the optical mixer 3 via the optical fiber cable 2, and the optical mixer 3
n optical signals of ~λn are combined and output as one optical signal to the optical fiber cable 4a. The optical modulator group 1, the optical fiber cable 2, and the optical mixer 3 constitute a transmitting device 8.

On the other hand, the spectrometer 5 uses the optical fiber cable 4
One optical signal is input via b. This optical signal is the same type of signal as the optical signal output from the transmitting device 8, and is obtained by combining n optical signals of different wavelengths λ1 to λn into one optical signal. The spectrometer 5 decomposes one input optical signal into n optical signals of different wavelengths λ1 to λn, and sends them to the optical demodulator group 7 via the optical fiber cable 6. The optical demodulator group 7 receives different input wavelengths λ
1 to λn to electrical signals SIG1 to SIG in corresponding optical demodulators 17-1 to 17-n, respectively.
n and output. The spectrometer 5, optical fiber cable 6, and optical demodulator group 7 constitute a receiving device 9.

[0009]

As explained above, the multiplex optical communication system of the present invention uses a plurality of optical signals of different wavelengths on the transmitting side, combines them and transmits them as one optical signal, On the receiving side, by receiving a single optical signal, decomposing it into multiple optical signals with different wavelengths, and regenerating them into electrical signals even if they are demodulated individually, even with a low modulation frequency. This has the effect of being able to transmit data with small distortion.

[Brief explanation of the drawing]

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

[Explanation of symbols]

1. Optical modulator group 2 Optical fiber cable 3. Optical mixer 4a Optical fiber cable 4b Optical fiber cable 5 Spectrometer 6. Optical fiber cable 7 Optical demodulator group 8 Transmitting device 9 Receiving device 11-1 to 11-n Optical modulator 17-1 to 17-n Optical demodulator

Claims (3)

[Claims] 1. An optical modulator group comprising a plurality of optical modulators that input one electrical signal among a plurality of different electrical signals, convert it into optical signals of mutually different wavelengths, and output the optical signals; a transmitter including an optical mixer that inputs multiple optical signals of different wavelengths from a group of devices and outputs a single optical signal that combines them; and a transmitter that combines multiple optical signals of different wavelengths from each other. a spectrometer that inputs one optical signal of the same type as the optical signal sent out from the transmitter, divides it into a plurality of optical signals of different wavelengths, and outputs the divided optical signals; and a plurality of optical signals from the spectrometer. 1. A multiplex optical communication system comprising: a receiving device comprising an optical demodulator group having a plurality of optical demodulators that input one optical signal, regenerate it into an electrical signal, and output the electrical signal. 2. An optical modulator group comprising a plurality of optical modulators that input one electrical signal among a plurality of different electrical signals, convert it into optical signals of mutually different wavelengths, and output the optical signals; 1. A multiplex optical communication system comprising a transmitting device including an optical mixer that inputs a plurality of optical signals of different wavelengths from a group of devices and outputs a single optical signal obtained by combining them. 3. A spectrometer that inputs a single optical signal obtained by combining a plurality of optical signals with different wavelengths, and divides and outputs the multiple optical signals with different wavelengths, and a plurality of optical signals from the spectrometer. A multiplexing system characterized by comprising a receiving device comprising a group of optical demodulators having a plurality of optical demodulators that input one optical signal among the main optical signals, regenerate it into an electrical signal, and output the electrical signal. Optical communication method.