JPH01319336A - Automatic equalization system for transmission line - Google Patents

Abstract

PURPOSE:To improve the stability of a current of a DC closing circuit and to make a voltage detection circuit small in size by applying voltage conversion to the current of the DC closing circuit by means of an automatic line equalizer so as to control the equalizer thereby obtaining a prescribed output level and shaping its waveform. CONSTITUTION:A DC power supply 13 forms the DC closing circuit via a load resistor 12, a relay coil 11, a transmission line 20, a relay coil 31, a load resistor 32 and grounding points 33, 14. The output side of the relay coil 31 of a data reception section 30 is connected to an equalizer 41 of an automatic line equalizing section 40. The equalizer 41 adjusts the output level of the inputted reception data by a command of the voltage detection circuit 42 to give an output to a reception data extraction path 50. The voltage detection circuit 42 detects the voltage drop across a load resistor 32 in the DC closing circuit via the transmission line 20, informs it to the equalizer 41, thereby selecting the equalizing circuit to obtain a prescribed output level and an equalized waveform. Thus, the current of the DC closing circuit is made stable and the voltage detection circuit 42 is miniaturized.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention automatically adjusts the received data to a predetermined output level when receiving data transmitted through transmission lines with different transmission conditions, and also shapes the waveform and outputs the data. This paper relates to an automatic equalization method for transmission lines.

[Conventional technology]

Conventional transmission line automatic equalization methods detect the signal level of the received data waveform, which has been subjected to attenuation distortion and waveform distortion due to the line, and automatically adjust the waveform signal level to a higher level if it is lower than a predetermined output value, or lower if it is higher than the specified output value. It also had an automatic line equalizer that shaped the waveform.

This will be explained with reference to FIG. In FIG. 2, the transmission line 20 has a data transmitter 60 and a data receiver 70 at both ends.
and are connected to respective relay rings 61 and 71.

The output of the data receiving section 70 is connected from the secondary winding of the relay coil 71 to the received data output path 50 via the equalizer 41 of the automatic route equalizing section 80 . The automatic route equalization unit 80 is the equalizer 4
It has a signal level detection circuit 81 which inputs the output of 1, detects the signal level, and feeds back the output effect to the equalizer 41. The signal level detection circuit 81 employs means for calculating and detecting the power, or means for detecting the waveform apex of the received data signal waveform and adjusting the equalizer.

[Problem to be solved by the invention]

As mentioned above, the conventional transmission line automatic equalization method feeds back the self-output of the received signal wave, so the circuit for power calculation is complicated and large, and the detection of the waveform apex is affected by the amount of code and interference. There was a problem that distortion occurred and errors were large.

An object of the present invention is to provide an automatic equalization method for transmission lines that solves the above problems.

[Means to solve the problem]

The automatic equalization method for a transmission line according to the present invention includes a data transmitter that supplies DC power to the transmission line through a load resistor, and a data transmitter that is provided opposite to the data transmitter to supply earth air to the transmission line through the load resistor. a data receiving unit that outputs received data via a relay ring connected to the transmission line while cutting off direct current and coupling to the transmission line;
The automatic line equalization section adjusts the received data inputted from the data reception section to a predetermined output level according to the voltage value detected from the load resistance of the data reception section, shapes the waveform, and outputs the same.

[Effect]

The automatic transmission line equalization method using the above means detects the direct current resistance of the transmission line and controls the equalizer to maintain the output level at a predetermined value and shapes the waveform to improve the signal-to-noise ratio. .

〔Example〕

Next, an automatic equalization method for transmission lines according to the present invention will be explained with reference to the drawings.

FIG. 1 is a block diagram showing one embodiment of the present invention. In FIG. 1, a data transmitter 10 for transmitting data is connected to a data receiver 3° via a transmission path 20, and the data is further connected to a received data extraction path 50 via an automatic line equalizer 4o.

The data transmitter 10 includes a relay ring 11. It has a load resistance R12 and a DC power supply 13, and the ground air 14 is connected to the DC power supply 13. Load resistance 12. It is connected to the transmission line 20 via the relay ring 11. The data receiving section 3o connects the transmission line 20 to the input side of the relay ring 31 and supplies earth air 33 via a load resistor R32. Therefore, the DC power supply 13 has a load resistance 12. Relay wire ring 11. Transmission line 20. Relay wire ring 31. Load resistance 32. A DC closed circuit is formed via the ground air 33 and the ground air 14.

The output side of the relay ring 31 of the data receiving section 30 is connected to an equalizer 41 of an automatic line equalization section 4o via an amplifier. Equalizer 41 adjusts the output level of input received data according to instructions from voltage detection circuit 42 and outputs it to received data extraction path 50 . The voltage detection circuit 42 detects the voltage drop across the load resistor 32 due to the DC closed circuit described above via the transmission line 20, and notifies the equalizer 41 of the voltage drop to obtain a predetermined output level and equalized waveform. let them choose. The formation of the DC closed circuit including the transmission line 2o is not limited to the above description.

〔Effect of the invention〕

According to the automatic transmission line equalization method of the present invention, the automatic line equalization unit converts the current value of the DC closed circuit of the transmission line into voltage to control the equalizer, obtain a predetermined output level, and generate a waveform. Since the structure is configured to shape the current value of the DC closed circuit, the stability of the current value of the DC closed circuit and the miniaturization of the voltage detection circuit can be realized.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of a conventional automatic equalization system for a transmission line, and FIG. 2 is a Zorrock diagram showing an example of the conventional method. 10... Data transmission section, 11.31...
・Relay wire ring, 12, 32...Load resistance, 13.
・Mark・DC power supply, 14.33... Earth air, 20・
・・・Transmission line, 3o・old・data receiving section, 40・
... Automatic line equalization section, 41 ... Equalizer,
42... Voltage detection circuit, 50... Reception data extraction path.

Claims (1)

[Claims] A data transmitter that supplies DC power to the transmission line via a load resistor; a data receiving unit that outputs received data via a relay ring coupled to a transmission line; and a data receiving unit that outputs received data input from this data receiving unit to a predetermined output according to a voltage value detected from a load resistance of the data receiving unit. An automatic line equalization system for a transmission line, comprising: an automatic line equalization unit that adjusts the level, shapes the waveform, and outputs it;