Data e.g. voice, transmitting method for e.g. powerline transmission type modem, involves estimating common mode current on conductors, finding adaptation impedance to reconstruct current and injecting current in conductor in opposite phase

摘要

#CMT# #/CMT# The method involves estimating common mode current carried on each of several conductors by performing recursive least mean square type adaptive filtering. An adaptation impedance of the conductor is determined to reconstruct the common mode current estimated on the conductor. The adaptation impedance is chosen such that a differential mode voltage between the conductors is not altered. The reconstructed common mode current is injected in the conductor in opposite phase. #CMT# : #/CMT# Independent claims are also included for the following: (1) a device for connecting a client terminal to a communication network (2) a computer program comprising program code instructions for executing steps of a data transmitting method. #CMT#USE : #/CMT# Used for transmitting data e.g. voice and multimedia data, in differential mode on a bifilar link such as electric line or twisted copper cable pair, towards a receiver equipment (claimed) e.g. powerline transmission or xDigital subscriber line (xDSL) type modem, which is connected to user equipment e.g. telephone, computer and server, using wireless fidelitystandard. #CMT#ADVANTAGE : #/CMT# The injection of constructed common mode current in the conductor in opposite phase suppresses the common mode current, which disturbs data transmission in differential mode, thus preventing the radiation of electromagnetic fields from affecting the domestic apparatus or radio amateur service. The method presents a reduced sensitivity to the dis-symmetry of the cable pairs, thus permitting to transmit the data in a large range of transmission frequencies. The method does not affect the useful information to be transmitted and can be implemented in a simple and inexpensive manner. #CMT#DESCRIPTION OF DRAWINGS : #/CMT# The drawing shows a flowchart representing the technique of reducing the common mode effects.