In the report we find parts of a satellite system, transponders, ground stations, components, frequency bands used among other connections. Transponder: A device that performs the function of reception and transmission.
Basically there are two types of transponders: the liabilities and assets.
Liabilities: Those elements that are identified by scanners, robots or computers, such as magnetic cards, credit cards, or spiral-shaped labels that carry products from stores. This involves interacting with a sensor that contains decodification information and transmit it to the data center. Generally, these transponders have a very limited scope, the order of a meter.
Assets: These are used in positioning systems, navigation and positioning. In more concrete terms, one can say that an active transponder is any chain of interconnected units or teams in series on a channel, which modify and adjust the signal from the receiver (usually receiving antenna) to the issuer (usually station antenna) with To transmit the information received. In some cases the term is used in a strictly incorrect to refer to the signal amplifier which is located just before the element issuer. In these systems, the transponder responds to a different frequency than what was asked, and both the input and output data are preset in advance. In these cases the scope is huge, both to be used without problems in the current transmission equipment in space (satellite television).

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