| 摘要 |
<P>PROBLEM TO BE SOLVED: To detect a carrier that does not depend on a bit rate by using a costas detector to perform FFT (fast Fourier transform) of a phase error of the carrier when detecting a PSK (phase shift keying) modulated wave carrier. <P>SOLUTION: A carrier frequency is detected by performing FFT of an output of the costas detector for acquiring a carrier frequency. Since a frequency component outputted by the costas detector is doubled in a BPSK modulation (binary phase shift keying) mode and is quadrupled in a QPSK (quadrature phase shift keying) modulation mode, values obtained by multiplying the frequency component by 1/2 and 1/4 become an actual carrier frequency. A PLL loop is driven in the frequency to synchronize the carrier. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
