Section III. PRINCIPLES OF OPERATION - TM-11-5895-1179-130015

TM 11-5895-1179-13 * EE132-EA-OMP-010/E106 KY883 * TO 31S1-2GSC-161

Section III. PRINCIPLES OF OPERATION

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General Theory

Communications Links Overview. Various satellite communications links are shown in figure 1-4. Each surface

vehicle, airplane, ship or ground station has a computer, teletype unit, or other similar device that uses and creates binary

data in the course of talking to other similar devices that could be anywhere in the world. These devices are linked together

by several means, including the satellite links. Normally, the purpose of the encoder-decoder is to provide coding and

decoding functions that improve the reliability of digital data transmissions over the communications link (Mode A). The

encoder-decoder can also protect a communications channel when an enemy is attempting to jam communications (Mode

B) and when signal outages occur while ships in the communications channel switch their antennas (Mode C).

Figure 1-4. Satellite Communications

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