Introduction To Multiplexing
Definition Multiplexing is used for the transmission of a plurality of information channels over a single transmission medium. An information channel may be a telephone voice channel, data channel, or…
Essential Concepts In Transmission
Introduction In this section we discuss two-wire and four-wire transmission and two impairments that are commonly caused by two-wire-to-four-wire conversion equipment. These impairments are echo and singing. The second part…
Introductory Switching Concepts
All local telephone switches have, as a minimum, three functional elements: concentration, distribution, and expansion. Concentration and expansion were discussed in Section 4.3.3. Viewing a switch another way, we can…
The Essential Functions of a Local Switch
As we mentioned above, means are provided in a local switch to connect each subscriber line to any other in the same exchange. In addition, any incoming trunk must be…
Introduction To Switching
In this section our concern is telephone switching, the switching of voice channels. We will deal with some switching concepts and with several specifics. Switching was defined in Section 4.1…
Transmission And Switching: Cornerstones Of A Network
Transmission And Switching Defined The IEEE defines transmission as the propagation of a signal, message, or other form of intelligence by any means such as optical fiber, wire, or visual…
Level
Level is an important parameter in the telecommunications network, particularly in the analog network or in the analog portion of a network. In the context of this book when we…
Voice Transmission
Loudness Rating and Its Predecessor Historically, on telephone connections, the complaint has been that at the receiving telephone the distant talker’s voice was not loud enough. “Hearing sufficiently well” on…
Quality Of Service And Telecommunication Impairments
OBJECTIVE Quality of service (QoS) was introduced in Section 1.4. In this chapter we will be more definitive in several key areas. There are a number of generic impairments that…
Radio Transmission
Up to now we have discussed guided transmission. The signal is guided or conducted down some sort of a “pipe.” The “pipes” we have covered included wire pair, coaxial cable,…
