Communication Systems

Communication at its most basic level involves three elements ─ the source, the message and the destination. A general outline of features common to all practical communication systems is shown below:

Fig.3. Communication Systems.

Brief explanations follow of the terminology used.

• Encoding: all messages originate in a person’s mind and the process of encoding is the way that the message is written down or spoken in order to be able to communicate with another person. Variation in word connotation by different people can alter the meaning of a message and voice emphasis and/or facial expressions and/or gestures all play a part in the encoding process when conversation is used. It will be realised that the way we convey meaning by the written word, figures, diagrams, and speech is an individual process.

• Channel: the means by which the information is carried, e.g. the internal mail system, external postal services, telephone and telecommunication networks, television, adio, satellite links and so on. Channels are not perfect because distortion, losses and delays may occur. Care must be taken by the MIS designer to ensure that the correct type of channel is used having regard to such matters as urgency, sensitivity, need for security and accuracy, type of information, cost effectiveness.

• Noise: the term used in communication theory for anything which causes the message at the receiver to be different from the message that went into the transmitter. For example, poor or illegible writing, accents, bad form design, poor picture quality, loss or damage, actual physical noise etc.

• Decoding: this is the process of achieving understanding from the message. I general, people read, see and hear what they want to read, see and hear so that decoding is an individual process. Different people are likely to derive different meanings from the same message, influenced by their experience, attitudes and value systems.

Numerous methods are used to ensure that messages are properly received and understood, particularly if they contain urgent or important items.

Examples include:

• repetition of important words or figures

• confirmatory letters or fax messages following meetings or telephone calls

• multiple copies of the message

• repeated V.D.U. screening at intervals.

Most communication systems deal readily with hard communications i.e. where there is some tangible record of the information. For example; letters, memoranda, tape/disc recordings etc. Where information is in a less concrete form, such as the tone of voice, body language, facial expression, it is known as soft communication. For obvious reasons these nuances are difficult to transmit through formal channels although these less tangible characteristics provide assistance in interpreting or judging the quality of a message and are thus important in making information more useful.