摘要 |
A differential demodulator has a region discrimination unit that generates a discrimination signal indicating the phase region of a complex-valued received signal. A discrimination signal delay unit, a comparison unit, and a switching unit then single out a minimal computational procedure necessary for demodulation. The procedure is carried out by one of two decision units and, when necessary, by a received signal delay unit and a multiply-add operation unit. The multiply-add operation unit performs only a multiplication operation on the imaginary part of the received signal and the real part of the delayed received signal, a multiplication operation on the real part of the received signal and the imaginary part of the delayed received signal, and a subtraction operation on two real numbers. A selection unit outputs a decision signal generated by the one of the decision units as the demodulated signal. |