Telecommand
From Wikipedia, the free encyclopedia
 |
This article does not cite any references or sources. (April 2007) Please help improve this article by adding citations to reliable sources. Unverifiable material may be challenged and removed. |
A telecommand is a command sent to control a remote system or systems not directly connected (e.g. via wires) to the place from which the telecommand is sent.
Contents |
[edit] Examples
- Control of a TV from the sofa
- Remote guidance of weapons or missiles
- Control of a satellite from a ground station
[edit] Transmission of commands
For a Telecommand (TC) to be effective, it must be compiled into a pre-arranged format (which may follow a standard structure), modulated onto a carrier wave which is then transmitted with adequate power to the remote system. The remote system will then demodulate the digital signal from the carrier, decode the TC, and execute it. Transmission of the carrier wave can be by ultrasound, infra-red or other electromagnetic means.
[edit] Encryption
To prevent unauthorised access to the remote system, TC encryption may be employed.
