PURPOSE: To simplify the converter without use of a ROM or the like by providing an absolute value comparator comparing in-phase and orthogonal components to obtain a distance from an origin on a complex plane respectively, a selector selecting sets of output bits and a decoder outputting angle data on the complex plane from respective output on the converter.
CONSTITUTION: An absolute value comparator A' compares absolute values of in-phase components I-ch and orthogonal components Q-ch in terms of the absolute values which receives data 101, 102 being demodulated complex base band digital signals of digital angular modulation waves to obtain a distance from an origin on a complex plane. A selector 104 selects sets of bits B comprising the most significant bit of the in-phase signal and other bits than the most significant bit of the orthogonal signal and sets of bits A comprising the most significant bit of the orthogonal signal and other bits than the most significant bit of the in-phase signal from the outputs of the absolute value comparator. Then a decoder 105 receiving the outputs of the absolute value comparator and the selector 104 outputs angle data on the complex plane. The complex angle modulator is realized with simple circuit configuration without use of a ROM in this way.
KUNIEDA MASANORI
MATSUBARA NAOKI
