Introduction to Telecommunications: Analog Voice and Data Systems by Dover Thomas

Author:Dover, Thomas [Dover, Thomas]
Language: eng
Format: epub
Publisher: Thomas K. Dover - Dover Telecommunication Services
Published: 2014-10-03T16:00:00+00:00

Echo

Echo takes place when you talk to yourself! Echo is a major problem in the following cases:

2W hybrid circuits.

Cellular circuits using 2W connections to switches.

Terminating equipment.

Unbalanced bridges and terminations.

Echo is also called loop-around or loop-back and causes many problems in voice and data circuits. Echo is typically not a problem in 4W circuits.

DSL is prone to echo because it uses a 2W facility to pass bi-directional data.

Echo cancellation is a function of taking the out-of-phase signals returning to the source and using coherent addition of power to cancel the signal voltage. Echo cancellation equipment is external to channel modems and connected to the 2W side of the circuit.

Download

Copyright Disclaimer:
This site does not store any files on its server. We only index and link to content provided by other sites. Please contact the content providers to delete copyright contents if any and email us, we'll remove relevant links or contents immediately.