| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a symbol synchronization method and a digital demodulator which allow shortening time to a symbol synchronization. <P>SOLUTION: When a modulating signal is digital-demodulated, the symbol synchronization method makes a midpoint detect as a zero crossing point when codes of two continuous symbol points differ, and makes a symbol point close to an ideal symbol point based on the zero crossing point. Further, after the step of detecting the zero crossing point, the method provides a step of detecting a symbol/zero cross reversal condition in which an amplitude of the symbol point becomes approximately zero, and makes compensation for 0.5 symbols perform when the symbol/zero cross reversal condition is detected. Moreover, the step of detecting the symbol/zero cross reversal condition detects as a symbol/zero cross reversal condition, when the absolute value of an amplitude value of the zero crossing point is larger than the sum of the absolute values of amplitude values of two symbol points. <P>COPYRIGHT: (C)2010,JPO&INPIT |
