JPH04213249A - Method of connecting data transmission line and data transmission line connected by using the method - Google Patents

Abstract

PURPOSE:To reduce the cost of the entire system by applying serial parallel conversion to a digital signal sending a high speed data transmission line and connecting a data subject to parallel conversion to plural low speed transmission lines. CONSTITUTION:A data is sent to a high speed data transmission line F (comprising a optical fiber and called a high speed optical LAN) at a high speed in nearly 100Mbps and sent to a low speed data transmission line M (comprising plural metallic cables and called a branch line LAN) at a low speed in nearly 10Mbps. A conversion circuit is provided to a relay station S1 of the high speed LAN. A serial data through the optical LANF is converted into an electric signal by an O/E converter to be a 10-bit parallel data and inputted to the branch LANM. The parallel signal returned through the branch line LAN is converted again into the optical signal and sent to a succeeding station. The high speed data transmission line and the low speed data transmission line are connected smoothly without decreasing the data transmission speed entirely to reduce the cost of the entire system.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of connecting a low-speed data transmission line to a high-speed data transmission line capable of high-speed data transmission using an optical fiber or the like, and to a data transmission line connected in this manner.

0002

[Background Art] Normally, when transmitting high-speed digital signals on a data transmission line, a high-speed transmission medium such as light is required, and when signal processing is performed at each relay terminal station, an optical branch that handles light is required. This requires expensive and complicated elements such as photoelectric converters and photoelectric converters. When connecting a data transmission line to such a high-speed data transmission line within a limited area, such as within a factory, it is necessary to use metallic cable instead of optical fiber or other high-speed transmission line for economical reasons. There are cases where it is desired to use a low-speed transmission line such as This is because if a low-speed transmission line such as a metallic cable is used, the above-mentioned expensive elements are no longer necessary, and only commonly used electronic elements are sufficient.

0003

[Problems to be Solved by the Invention] However, simply connecting a low-speed transmission line such as a metallic cable to a high-speed transmission line such as an optical fiber will naturally limit the signal transmission speed of the transmission network to the upper limit of the low-speed transmission line. The signal transmission speed of the entire system decreases. Therefore, the present invention provides a method that allows even a low-speed data transmission path to be connected to a high-speed data transmission path without reducing the signal transmission speed of the system, and a data transmission path connected in this way. The purpose is to

0004

[Means for Solving the Problems] The data transmission line connection method of the present invention to achieve the above object performs serial/parallel conversion on digital signals transmitted through a high-speed data transmission line, and performs the parallel conversion. This method connects the transmitted data to multiple low-speed data transmission lines.

Furthermore, the data transmission line of the present invention has a high-speed data transmission line arranged in a loop, and a conversion circuit for performing serial/parallel conversion on the digital signal being transmitted is installed at both ends of the high-speed data transmission line. A plurality of low-speed data transmission lines are provided, respectively, and both ends of a plurality of low-speed data transmission lines for transmitting parallel-converted data are connected to each of the conversion circuits.

[0006]

[Operation] According to the method for connecting the data transmission line with the above configuration, by performing serial/parallel conversion on the digital signal transmitted on the high-speed data transmission line, the data transmitted at high speed is damaged. You can slow down to low speed without any problems. Then, the parallel-converted data can be connected to a plurality of low-speed data transmission lines and sent out as is, allowing low-speed transmission. In this case, since the data is serial/parallel converted, the transmission speed of the entire data transmission path does not decrease.

Further, according to the data transmission path of the present invention, conversion circuits that perform serial/parallel conversion on digital signals being transmitted are provided at both ends of the loop-shaped high-speed data transmission path, so that parallel conversion is performed. Since both ends of the low-speed data transmission line that transmits the data are connected to each of the conversion circuits described above, a loop using the low-speed data transmission line is connected to the loop-shaped high-speed data transmission line, and the transmission speed of the high-speed data transmission line is can be added without dropping.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples will be explained in detail below with reference to the accompanying drawings showing examples. Figure 1 shows serial/parallel conversion of digital signals transmitted through a high-speed data transmission line (hereinafter referred to as "high-speed optical LAN") consisting of optical fiber cables F including relay stations S1, S2, and S3, and the parallel conversion. This figure shows a configuration in which the transmitted data is connected to a transmission line consisting of a plurality of metallic cables M connecting relay stations T1, T2, T3, and T4, that is, a plurality of low-speed data transmission lines (hereinafter referred to as "branch LAN"). .

[0009] In this embodiment, the high-speed optical LAN is about 100
Data is sent at a speed of Mbps, and the branch LAN can send data at a speed of about 10 Mbps. Therefore, when connecting both transmission lines, it is necessary to convert the speed, so the relay station S1 of the high-speed optical LAN
A conversion circuit is provided. As shown in FIG. 2, this conversion circuit consists of 10-bit shift registers B1,
B2, etc., and the 100Mbps high-speed serial data (data transmitted one bit at a time) sent through the optical fiber cable F is sent to the converter O/E.
This converted electrical signal is input to the shift register B1, taken out as 10-bit parallel data (data that is divided into two or more transmission lines and transmitted simultaneously), and input to each branch LAN. be done.

[0010] Therefore, the speed of data transmitted over the branch LAN has decreased to 1/10, 10 Mbps, so
It is possible to pass through the branch LAN without any problem. Branch line LA
The parallel signal that has returned after going around N is converted again into a 100 Mbps serial signal by shift register B2, converted into an optical signal by converter E/O, and sent to the next station via optical fiber cable F.

[0011] With the above configuration, a branch LAN with a slow transmission speed can be connected to a high-speed optical LAN for data transmission without reducing the speed of data transmitted through the optical fiber cable F.

0012

As described above, according to the data transmission path connection method of the present invention, serial/parallel conversion is performed on digital signals transmitted through a high-speed data transmission path, and the parallel-converted data is By connecting to a plurality of low-speed data transmission paths, it is possible to smoothly connect the high-speed data transmission path and the low-speed data transmission path without reducing the overall data transmission speed.

Further, according to the data transmission line of the present invention, serial/parallel conversion circuits are provided at both ends of the loop-shaped high-speed data transmission line, and both ends of the low-speed data transmission line for transmitting parallel-converted data are provided. Since the converter is connected to each of the conversion circuits described above, a loop using a low-speed data transmission path can be added and used without reducing the transmission speed of the loop-shaped high-speed data transmission path. Furthermore, the lines and elements constituting this low-speed data transmission line can be compatible with low-speed transmission, and the overall cost can be reduced.

[Brief explanation of the drawing]

[Figure 1] High-speed optical L using serial/parallel conversion method
FIG. 2 is a diagram showing the configuration of a transmission line in which a branch LAN is connected to an AN.

[Figure 2] Serial/
FIG. 2 is a block diagram showing the configuration of a parallel conversion circuit.

[Explanation of symbols]

B1, B2 shift register, F　Optical fiber cable, M metallic cable,

Claims (2)

[Claims] 1. A method for connecting a data transmission line, which performs serial/parallel conversion on a digital signal transmitted over a high-speed data transmission line, and connects the parallel-converted data to a plurality of low-speed data transmission lines. Claim 2: A high-speed data transmission path is provided in a loop, and conversion circuits that perform serial/parallel conversion on the digital signal being transmitted are provided at both ends of the high-speed data transmission path, and the parallel-converted data is 1. A data transmission line connected using a data transmission line connection method, characterized in that both ends of a plurality of low-speed data transmission lines for transmitting the data are connected to each of the conversion circuits.