http://www.dslreports.com/forum/r18035 en Wed, 09 Dec 2009 09:53:18 EDT Wed, 09 Dec 2009 09:53:18 EDT http://www.dslreports.com/forum/remark,18035 DrTCP : My $0.02 regarding DMT upstream/downstream frequency usage mentioned in the article:

DMT uses echo cancellation. As a result upstream/downstream frequencies may overlap. That's the modem can use the same frequency to transmit and recive at the same time. The difference, is that downstream frequencies extend much higher than upstream frequencies.

Some implementations of DMT choose to do away with echo cancellation and separate upstream/downstream frequencies. But, again this is just an implementation issue. To satisfy full rate (8Mbps) downstream, upstream and downstream freqencies must overlap and echo cancellation must be used by DSLAM and modem.

Tolunay
]]> http://www.dslreports.com/forum/remark,18035 Tue, 27 Jun 2000 03:51:11 EDT