RU19240U1 - SVP-03T / 04R VIDEO-TRANSFER SYSTEM - Google Patents

Description

SVP-03T / 04R twisted pair video transmission system.

The utility model relates to video signal transmission systems via

twisted pair wired communication lines providing

noise immunity and correction of the communication line and can be used

in branched television surveillance systems.

Known technical solution A.S. No. 1543567 Al, H04N5 / 21 02/15/1990

"A device for video correction, which contains a filter

bass, differentiation unit, adjustable amplifier,

bilateral limiter. Input noise level

the video signal is regulated by the selection of weights

adjustable amplifier.

The disadvantage of this device is the impossibility of correction

symmetrical video signal.

The program is currently gaining great popularity.

video signal over a twisted pair cable. The transmission principle is based on

converting an unbalanced video signal to a balanced one,

broadcasting the received bipolar video signal over twisted pair with

subsequent inverse transformation and correction of the communication line. Such

the principle of video transmission is called differential or

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The purpose of the claimed utility model is to create a system for implementing the claimed differential principle for transmitting a signal over a twisted pair cable and for correcting the transmitted symmetric video signal.

It provides high noise immunity when broadcasting in a single multi-pair cable several types of signals of different types (video, sound, power, telephony).

In FIG. 1 shows a functional diagram of a twisted pair video transmission system, which contains: a video camera - 1, a coaxial cable - 2, a transmitter - 3, a transmission line in the form of a twisted pair cable - 4, a receiver - 5, a coaxial cable - 6, a monitor - 7, the first and the second power supply units - 8, 9, with blocks 1-7 connected in series, the outputs of power supplies 8 and 9 connected to the power inputs of the universal voltage stabilizers of the transmitter and receiver. In FIG. 2 shows a diagram of a twisted pair signal transmitter, which contains a coaxial cable -1, a matching unit with a signal source -2, a pre-corrector-3, a unit for converting the signal to a balanced view4, a protection and matching unit with a line - 5, twisted pair - 6, universal voltage stabilizer - 7, and blocks 1-6 are connected in series. All transmitter units are powered from a universal voltage regulator 7. In Fig. 3, a functional diagram of a video signal receiver is shown in

twisted pair, which contains a twisted pair - 1, a protection and matching unit with a line - 2, a differential conversion unit - 3, an amplifier corrector for the amplitude-frequency characteristic of a line-4, a matching unit with a signal receiver - 5, a coaxial cable - 6, a universal voltage regulator -7. Blocks 1-6 are connected in series. All receiver units are powered by a universal voltage regulator 7.

The claimed system operates as follows. The general principle of operation of the system is described in accordance with FIG. 1 The video signal from the camcorder through a coaxial cable arrives at the transmitter, from which it is fed through a twisted pair cable to a receiver, from which it is transmitted through a coaxial cable to a monitor or some other terminal device. The operation of the transmitter is described in accordance with figure 2. An unbalanced signal on the coaxial cable arrives at the matching unit with the signal source. In the pre-corrector, preliminary correction is carried out depending on the cable length. Then, the corrected signal is converted into a symmetric form in block 4. Twisted pairs are subject to electrostatic and lightning pickups, therefore, protection block 5 is provided, which contains a gas-discharge device for shunting electrostatic charges to earth.

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3 At the input of the receiver (Fig.Z), the signal comes through a twisted pair -1, and

to the protection unit and coordination with the line. Next, the signal is fed to the input of the differential conversion unit, where the inverse transformation of the symmetric signal into the asymmetric takes place. The amplifier corrector of the amplitude-frequency characteristics of line 4 provides amplification with the possibility of adjustment and correction “roughly using the P2, PZ switch and fine adjustment of the low and high frequencies depending on the length of the twisted pair.

The matching unit with the signal receiver 5 negotiates with the signal receiver. Further, the signal corrected in this way can be applied to any monitor terminal device, VCR, etc.

The transmitter and receiver are supplied with power from any sources of direct or alternating voltage 24v. The abbreviation SVP-03T 04R stands for the name of the organization SPECVIDEOPROJECT, Inc. The claimed system can be widely used in the implementation of projects of television surveillance systems. An advantage of the claimed system is the use of twisted pairs instead of expensive coaxial lines and the possibility of transmitting a large number of video signals in one multi-pair cable.

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4 channels. In addition, in buildings under construction there are often free twisted

pairs that can be used to transmit the described symmetrical signals. Therefore, the use of this system to create branched television surveillance systems is cost-effective and technically justified, because allows you to transmit signals with the least distortion over long distances (up to 1500m).

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Claims (1)

A twisted pair video signal transmission system comprising a transmitter and a receiver connected by a communication line, characterized in that the communication line is made in the form of a twisted pair, the transmitter comprises serially connected matching unit with a signal source, a pre-corrector, a signal to symmetrical conversion unit and a protection unit, and coordination with a line, the output of which through a twisted pair is connected to the input of the receiver, which contains a protection and coordination block connected in series with the line, a differential conversion unit, amplifier - corrector amplitude-frequency characteristics of the communication line.