| 摘要 |
<P>PROBLEM TO BE SOLVED: To accurately detect a subcarrier by a simple configuration. <P>SOLUTION: A moving average part 151 calculates an average of signal levels in a signal d11 and a signal d12. A subcarrier correlation filter 152 calculates a correlation value of subcarriers for two periods by using a filter coefficient of 1/4 etu (Elementary Time Unit) sectional length. A synchronization processing part 154 detects a frame head based on signals d15, d16, and d17. A threshold determination part 155 determines whether or not subcarrier modulation is performed in each 1/2 etu section by comparing the level of the signal d15 with a threshold based on the timing of a signal d19, and specifies a series of the symbols expressed by an etu based on the timing of a signal d20. <P>COPYRIGHT: (C)2011,JPO&INPIT |
