Pulse Communication

Pulse Communication:

Measurement of Information in Communication System : Having said what information is not (it is not meaning), we now state specifically what information is. Accordingly, information is defined as the choice of one message out of a finite set of messages. Meaning is immaterial, in this sense, a table of random numbers may well contain as much Measurement of Information in Communication System as a table of world track-and-field records. Indeed, it may well be that a cheap fiction book contains more information than this textbook, if it happens to contain a larger number of choices from a set of possible messages …


Noise in Information – Carrying Channel: Noise in Information-carrying capacity of a channel. This idea will now be explored further, as will means of combating noise. Effects of Noise: That Noise in Information has some harmful effect has already been demonstrated. To quantify the effect, consider again the earlier suggestion that each letter in the alphabet could be represented by a different signal amplitude, using 32-scale code. If this were done, the information flow would be greatly speeded (according to the Hart­ley law), since each letter would now be represented by one symbol instead of five. Unless transmitting power were raised tremendously, noise …


Telegraphy in Electronic Communications : Telegraphy in Electronic Communications that employs typewriter like machines operating at a maximum speed of about 60 words per minute (wpm) to send written messages from one point to another. In telegraphy, a user lodges a written message for transmission at a telegraph or post office. The message is subsequently transmitted to the office nearest to the addressee, and delivered in typewritten form, perhaps after having been first telephoned through, if that was part of the request. Telex combines the above system with subscriber dialing techniques. The originator of the message composes the address of the message …


Telemetry in Electronic Communications : Telemetry in Electronic Communications consists of performing measurements on distant objects. Although hydraulic or wire circuits may be used for this purpose, this section will deal with radiotelemetry only, particularly as this form is now prevalent. The alternatives to radiotelemetry are either having observers on the spot or having some form of multitrack recorders on the site from which data may be collected when conve­nient. However, there are situations in which neither of these alternatives is possible, and in fact radiotelemetry arose in the early 1940s from the need to obtain in-flight information from fighter aircraft and …


Updated: May 1, 2020 — 5:10 pm