JPH04176225A - Multi-channel signal synchronization multiplex transmission system - Google Patents

Abstract

PURPOSE:To prevent the transmission speed from being increased due to multiplexing by providing a converter whose output level is changed depending on read of digital signals to the system. CONSTITUTION:A converter T receives n-sets of digital signals of each channel whose phases are arranged and outputs one level of 2<n> sets of voltage levels according to a clock. An electric signal includes information comprising the n-sets of signals and the signal speed is unchanged from a speed of one channel. The electric signal is distributed and sent through m-sets of transmission lines. A converter R at a receiver side having a function inverse to the converter T at the sender side demodulates the received signal into n-sets of digital information.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a system for synchronously multiplexing and transmitting multi-channel signals in the field of telecommunications.

[Conventional technology]

1-
,. .

The conventional multiplexing method is based on modern communication line theory (Morikita Publishing)
As described in , this is a method for time-division multiplexing transmission of multi-channel digital signals.

[Problem to be solved by the invention]

The above conventional technology does not take into consideration the increase in signal speed due to multiplexing of multi-channel digital signals, and when the types of ICs used increase and the speed per channel is high,
There were problems such as the multiplexed signal becoming extremely fast and difficult to implement in hardware.

The purpose of the invention is to avoid increasing the transmission rate by multiplexing.

[Means to solve the problem]

In order to prevent the transmission speed from increasing due to multiplexing of multi-channel digital signals, a converter whose output amplitude changes depending on the combination of digital signals is provided.

[Effect]

The converter converts a total of n digital signals taken from each of the n channels according to a clock into one of 2n amplitude values.

, 2° This allows the multiplexed electrical signal to have one amplitude value within its -clock, so that the signal speed does not increase. When an electric signal is sent from the transmitting side, it is possible to demodulate n pieces of digital data on the receiving side by using a converter having the opposite function to the converter based on the amplitude value.

Therefore, by using a converter, it is possible to perform synchronous multiplex transmission of n-channel signals without changing the signal speed.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

FIG. 1 is a system diagram of n-channel signal synchronous multiplex transmission. The information sources 1a, lb, and in are converted into digital signals by A/D converters 2a, 2b, . . . 2n, respectively, according to the clock from the clock source. The converter T aligns the phases of the digital signals and outputs one amplitude value out of 2n voltage amplitude values in accordance with the clock using a total of n digital signals from each channel. This is a multiplexed electrical signal. The electrical signal contains the information of n signals, but the signal rate is the same as that of the -channel. Electrical signals are distributed and transmitted using m transmission paths. On the receiving side, the signal is demodulated into n pieces of digital information by a converter R having the opposite function to the converter T on the transmitting side.

The digital information is restored to the information sources J to Jn by the D/A converters 3a to 3n. Through these series of operations, multi-channel synchronous multiplex transmission can be realized.

Now, the input and output of the converter T will be explained using FIG. For simplicity, consider the two-channel case. Converter T takes in digital signals from channels 1 and 2 in synchronization with the clock and adjusts the phases. The converter outputs a digital signal■. -■ Output one of the four. In this example, S(channel 1.channel 2)=
When (0, O), V=Vo; when S (0, l), V=V□.

When S (1, O), V=V2. S (1, L) (7
), then V=V. From Figure 2, it can be seen that the signal speed does not increase even if channels 1 and 2 are multiplexed.
· Recognize.

The above uses a baseband transmission method, but
A carrier system in which a multiplexed electrical signal is used as a modulation signal may also be used. - For example, a method can be considered in which amplitude modulation is performed using the amplitude value of the multiplexed signal on the transmitting side, and demodulation is performed on the receiving side to obtain the amplitude value.

Although m transmission lines are used in FIG. 1, m may be 1.

〔Effect of the invention〕

According to the present invention, the signal speed does not increase even when N multi-channel digital signals are multiplexed, so the following effects are achieved.

For example, consider a case where the signal speed of one signal channel is IOMHz and n=10. At this time, in the conventional method, the multiplexed signal is 100MHz, but in this method, the multiplexed signal is 100MHz.
It remains at 0 MHz. If it is about 10 MHz, it is possible to implement the IC using only TTL, but in the conventional system, it is necessary to use ECL. As a result, the number of types of power sources increases and the amount of power used also increases. This method does not have this problem by 1.4 degrees and can be said to be superior.

[Brief explanation of drawings]

FIG. 1 is a block diagram of n-channel signal synchronous multiplex transmission according to an embodiment of the present invention, and FIG. 2 is an explanatory diagram of the input/output relationship of the converter T when 1=2. ■a-]-n: Transmission side information source, 2a-2n: A/D converter, 3 a-3n: D/A converter, 4 a-4n
:Recipient information source.

Claims (1)

[Claims] 1. After digitizing signals from n different channels using the same clock source for each piece of information and adjusting the phase of each piece of digital information, reading the digital information at the same time, characterized in that it is equipped with a converter that converts the signal into one amplitude value (multiplexed electrical signal),
Multi-channel signal synchronous multiplex transmission system. 2. A multi-channel signal synchronous multiplex transmission system according to claim 1, wherein the multiplexed electrical signal is transmitted using m transmission lines and by a baseband transmission system or a carrier transmission system.