Nature of Information

Telecommunication provides a transport mechanism for information. Therefore, it is necessary to have basic knowledge on the subject of information for one to understand telecommunication.

Information comes in the form of spoken words (voice), image, computer data, video or written and printed documents. Information can be sent in its original/native form from the source to its destination (receiver), information is sent in the form of signals over a transmission medium. A block diagram below might help us visualize this.

Figure 3: Communication System

The source (e.g. voice, data, video, etc.) is the origin of the information. The destination (receiver) (e.g. radio, television, facsimile, computer, etc.) is the end of the terminal of the transmission of the information. Bearing in mind what we have just discussed, we can now define telecommunication as the process of transporting or passing information from source to destination over long distances. A number of intermediate devices are involved in this transfer of information (e.g. modems codecs, switches and so on). Some of these devices will be covered later in the course.

There is a wide variety of signals and media. Examples of media:

Physical media includes; copper wire (e.g. twisted pair or co-axial cable), glass or plastic. (E.g. fiber optic cable).

Wireless media includes; radio, infrared light, space or airwaves (e.g. microwaves, satellite and cellular). The signals take the form of a voltage varying with time. Many signals are in non-electric form (e.g. voice) when they start off. Transducers (e.g. microphone) change non-electric signals to electrical Signals. These electrical signals contain INFORMATION that is to be transmitted / sent.