FOUR CHANNELS WIRELESS VIDEO COMMUNICATION SYSTEM «MARK-TV MOBILE»

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System is designed for organizing of  movable wireless video communication.

The system consists of:
— transmitter  MARK-TV MOBILE/ TR;
— receiver      MARK-TV MOBILE/ R;
— 2 antennas (at will of the customer or Rod-antenna, or V-antenna are delivered).

Channel selection is carried out by the push-button switch. The output power of transmitter can be changed by control button. Inputs and outputs of audio and video signals, indicators of channels and radiated power and supply tumbler have mounted on the front panel. Storage battery is delivered by separate order.

SPECIFICATIONS

 Transmitter   Receiver
Frequency range 1700….2150 MHz 1700-2150 MHz
Band of frequencies of one channel 28 MHz 28 MHz
Power consumption 3,5 W 2,0 W
Noise factor 6 dB
Output power 100 mW
Power supply 12…16 V 12….16 V
Dimensions 200x95x22 mm 200x95x22 mm
Weight 500 g 500 g

 

Input impedance of antennas 50 Ohms
Communication range of one interval with rod antenna within the line-of-sight distance 300 mm
Directivity:
 — Rod-antenna 1,5 dB
 — V-antenna 10 dB
Angular aperture of V- antenna 600C

SYSTEMS OF LOCAL COMPUTER NETWORKS

Posted on by mmm

The system of operative communication is intended for organization of the data transmitting network by wireless.

Radio modems (RM), which operates in a monofrequent duplex mode with time division of reception-transfer and use of pseudo-casual sequences by number of elements 127 are used as radio stations.

Following structure of systems is proposed:

· central station (CS);

· 16 subscriber’s stations (SS) i.e. radio modems (RM).

Before the operation, addressing of RM is carried out by the cartridge with SS addresses and operating codes. The device (cartridge) with SS addresses and operation codes are moved from CS.

Number of subscribers in subgroup is 16, and number of subgroup in one region is 6.

In that case RM-s operate on one logical direction.

FOUR CHANNELS WIRELESS EXTENDER

Posted on by mmm

It is intended for creation of multi channel radiotelephone communication:

a) for subscribers of out-of-the-way and remote regions, where there are not enough telephone lines;

b) between automatic exchanges (AE);

c) between subscribers of commutators (C).

It is used for creation of special types of communication and for development of operative channels at extreme circumstances.

Wireless extender provides high noise-immunity and reliability of transmitting information, by using of spread-spectrum systems of communication and digital processing of data with additional coding of information.

On the long distances it can be used as repeater with using of additional extender. Using method of the digital transmission and signals’ processing removes the limitation of retransmissions coefficient.

Wireless extender consists of station complete (SC) and subscriber complete (SbC). Main units of SC and SbC are radio modem (RM) and matching unit (MU).

Diagram of radiotelephone communication based on wireless extender