A digital subscriber line communication system does not require the use of a plain old telephone service (POTS) splitter in the resident's home. Digital signal processing techniques are utilized to adapt to varying subscriber line conditions due to POTS telephone equipment. The digital signal processing...http://www.google.com.tw/patents/US6430219?utm_source=gb-gplus-share專利 US6430219 - Method of and apparatus for performing line characterization in a subscriber line communication system
