An apparatus and method for detecting signal points transmitted over a transmission line. A data transmitter encodes input data and maps this data in accordance with a Trellis Code Modulation technique. The mapped data is then modulated onto a particular carrier wave, and transmitted to a data...http://www.google.com.au/patents/US5717706?utm_source=gb-gplus-sharePatent US5717706 - Apparatus and method for detecting signal points using signal point-mapping 
