|Title of Invention
A HIERARCHICAL QUADRATURE AMPLITUDE MODULATION RECEIVER FOR CONTROL OF CENTER OF GRAVITY.
||The invention relates to a hierarchical QAM receiver for control of center of gravity, comprising: an input for receiving a hierarchical QAM signal, representing successive data points in the I-Q plane, each data point being in one of four quadrants. A level 1 decoder (304), responsive to a received data point, for detecting the quadrant in the I-Q plane of a received data point; a first circuitry (306, 308, 310), coupled to lthe hierarchical QAM signal input for translating the received data point in the I-Q plane such that a center point of the detected quadrant is translated to the neighborhood of the origin of the I-Q plane. A level 2 decoder (312), responsive to the translated data point for detecting the quadrant of the translated data point. A second circuitry (320, 322, 324), coupled to the hierarchical QAM signal input, being provided for calculating the location in the I-Q plane of the center-or-gravity of successive received data points in a quadrant. The first circuitry (306, 308, 310) additionally comprising circuitry for translating the received data point in the I-Q plane such that the calculated center-of-gravity location is translated to the origin of the I-Q plane.
in-pct-2002-656-kol-granted-reply to examination report.pdf