Signal point arrangement dispersion calculation circuit

Abstract

A signal point arrangement dispersion calculation circuit whose circuit scale is small. The phase of a demodulation baseband signal is turned by a 22.5° turning remapper (3) at a speed twice the speed of the symbol rate of the demodulation baseband signal. The signal point position of the demodulation baseband signal is found by a signal point arrangement conversion circuit (73) in accordance with the demodulation baseband signal and the baseband signal whose phase is turned by a phase turning circuit. The signal point arrangement of the demodulation baseband signal is converted into the position of the first quadrant in accordance with the found signal point position from the demodulation baseband signal and the baseband signal whose phase is turned 45° by the two successive rotations made by the 22.5° turning remapper (3), and the dispersion is obtained in accordance with the baseband signal whose signal point arrangement is converted.

Dependencies are inferred from the claim text.