| 摘要 |
<P>PROBLEM TO BE SOLVED: To attain digital demodulation having improved process efficiency by reducing an arithmetic operation quantity at the time of determination of a symbol of a QAM signal. <P>SOLUTION: A digital demodulator for demodulating a QAM signal has a quasi-synchronous detector for applying quadrature detection to the QAM signal, and a symbol determination section for determining the symbol of a signal having an I component and a Q component acquired in the quasi-synchronous detector. The symbol determination section solves the above problem by specifying a specific symbol on the basis of a rectangular region set for each of a plurality of symbols and a symbol adjacent to the specific symbol, and performing region determination on the basis of a polygonal region corresponding to each of the specific symbol and the adjacent symbol. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
