JPS6316793A - Optical receiving system - Google Patents

Abstract

PURPOSE:To remove a great loss occured by an optical switch circuit and to lengthen a transfer distance by converting n-number of optical signals into electrical signals in n-number of photoelectric convertors and executing a necessary selection in an electrical switch circuit according to the control signal so as to output the signal. CONSTITUTION:The titled system includes n-number of optical fiber transmission lines 11-1n, n-number of photoelectric convertors 21-2n, a switch circuit 30, a reception amplification circuit 50 where the output from the switch circuit 30 is inputted and amplified to output an output 70 and a bias circuit 40 giving a bias to the respective photoelectric convertors. The optical signals from the optical fiber transmission lines 11-1n are respectively converted into the electrical signals by the photoelectric convertors 21-2n and inputted in the switch circuit 30. The switch circuit 30 selects one of n-number of the electrical signals to output it according to a separately inputted control signal 60. And the output from the switch circuit 30 is amplified to the specified size in the reception amplification circuit 50 and the output 70 is outputted.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention is an optical fiber transmission system, particularly in a subscriber system, in which arbitrary information (or channels, hereinafter collectively referred to as (referred to as information).

〔overview〕

The present invention is an optical reception method that selects and converts arbitrary m (m<n) optical signals from n optical signals manually inputted from a plurality of 0 optical fiber transmission lines into electrical signals and outputs the electrical signals. In the conventional method, the above n optical signals are converted into electrical signals by n optical-to-electrical converters provided respectively, and the required selection is made and outputted by an electrical switch circuit according to the control signal. This eliminates the large loss caused by the optical switch circuit used for selection and increases the transmission distance.

[Conventional technology]

Conventionally, as this type of optical reception system, an optical switch system is known in which arbitrary information is selected using an optical switch, and a schematic diagram thereof is shown in FIG. Information from one optical fiber transmission line 11 to 1n is selected in the optical switch circuit 80 according to the control signal 60c, and outputted to the optical-to-electrical converter 20, which converts the optical signal into an electrical signal. The signal is converted into 0 and amplified by the receiving amplifier circuit 50a to obtain output cuff 0. Note that 40b is a bias circuit for the optical/electrical converter 20.

[Problem that the invention seeks to solve]

The above-mentioned conventional optical reception system using an optical switch has the advantage that only one optical/electrical converter is required, but has the disadvantage that the transmission distance is short because the optical switch itself has a large loss.

SUMMARY OF THE INVENTION An object of the present invention is to provide an optical reception method for an optical fiber transmission system that can extend the transmission distance by eliminating the above-mentioned drawbacks.

[Means for solving problems]

The present invention provides an optical reception system including a selection/conversion means for selecting/converting an arbitrary optical signal from among n optical signals inputted from a plurality of n optical fiber transmission lines into an electrical signal and outputting the electrical signal. n optical-to-electrical converters, wherein the i1 selection/conversion means is connected to each of the one optical fiber transmission line and converts the inputted optical signal into an electrical signal and outputs the electrical signal;
Input the n electrical signals outputted from this optical-electrical converter and select any m(
The present invention is characterized by comprising a switch circuit that selects and outputs m<n) electrical signals.

[Effect]

In the present invention, n optical-to-electrical converters are provided, and each of the n optical signals from the n optical fiber transmission lines is first converted into an electrical signal, and from among these converted electrical signals, the required A number of electrical signals are selected by an electrical switch circuit according to a control signal, and amplified to a predetermined magnitude by an amplifier circuit and output.

Therefore, the conventionally used optical switch circuit, which has a large loss, is no longer necessary, and since an optical/electrical converter and a switch circuit, both of which have extremely low loss, are used, the loss is reduced, and the transmission distance can be extended. .

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing a first embodiment of the present invention. In this embodiment, one optical fiber transmission line 11 to In and n optical-to-electrical converters each input an optical signal from each of the optical fiber transmission lines 11 to 1n and output a converted electrical signal. 21~2n, and this optical/electrical converter 21~
a switch circuit 30 which inputs the output of 2n and selects one of them and outputs it according to the control signal 60; a reception amplification circuit 50 which inputs the output of the switch circuit 30, amplifies it and outputs the output cuff 0; A bias circuit 40 that applies a bias to the optical-to-electrical converter is included.

Next, the operation of this embodiment will be explained. The optical signal from the optical fiber transmission line 11~In is transmitted to the optical/electrical converter 21~
2n, each is converted into an electrical signal and sent to the switch circuit 3.
It is input to 0. The switch circuit 30 selects and outputs one of the n electrical signals according to a control signal 60 that is separately input. And this switch circuit 30
The reception amplification circuit 50 amplifies the output from the output to a predetermined size and outputs the output cuff 0.

FIG. 2 is a block diagram showing a second embodiment of the present invention. This embodiment uses the control signal 60 in the circuit shown in FIG.
a is input to the bias circuit 40a in addition to the switch circuit 30, and the output thereof is stopped by controlling the bias of the optical/electrical converters 21 to 2n, so that the selection in the switch circuit 30 can be made more easily. It is.

FIG. 3 is a block diagram showing a third embodiment of the present invention. In this embodiment, m (m<n) reception amplifier circuits 51 to 5m are connected to the switch circuit 30a in the circuit shown in FIG. According to the control signal 60b, m electrical signals are extracted from among the n electrical signals outputted from 2n, and a predetermined amplification is performed to obtain m output cuffs 1 to 7m. .

A feature of the present invention is that in FIGS. 1, 2, and 3, the optical/electrical converters 21 to 2n and the switch circuit 30.
30a is provided.

〔Effect of the invention〕

As explained above, the present invention selects arbitrary m (m<n) outputs from among the outputs of n optical-to-electrical converters and connects them to m reception amplifier circuits, thereby achieving the following: It has the following effects.

■ The loss of the optical/electrical conversion circuit and switch circuit is extremely low, so it does not affect the transmission distance.

■ In the future, it will be effective if optical fiber transmission lines become cheaper and optical/electrical converter arrays (multiple optical/electrical converters integrated) and small multi-core optical connectors are put into practical use. This is a method.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the present invention. FIG. 2 is a block diagram showing a second embodiment of the present invention. FIG. 3 is a block diagram showing a third embodiment of the present invention. FIG. 4 is a block diagram showing a conventional example. 11~1n...Optical fiber transmission line, 20.21~2n
...optical/electrical converter, 30.30a-switch circuit,
40.40a, 40b...bias circuit, 50.50
a, 51~5m...reception amplifier circuit, 60.60a
, 60b, 60cm control signal controller 0.71~7m...
・Output, 80... Optical switch circuit.

Claims (1)

[Claims] (1) In an optical reception system that includes a selection/conversion means that selects and converts an arbitrary optical signal from among n optical signals inputted from a plurality of n optical fiber transmission lines into an electrical signal and outputs the electrical signal, the above-mentioned The selection/conversion means includes n optical-to-electrical converters connected to each of the n optical fiber transmission lines and converting the inputted optical signals into electrical signals and outputting the same, and the optical-to-electrical converters. and a switch circuit that inputs the n electrical signals outputted from the controller and selects and outputs any m (m<n) electrical signals from among them according to a control signal. Optical reception method.