| 摘要 |
<P>PROBLEM TO BE SOLVED: To solve the problems of conventional periodicity detection methods for a periodic signal, employing the partial correlation method that takes a long time to detect the period because there are many numbers of parameter combinations and that it is difficult to obtain the period of header information, because peaks are hard to be detected when the length of the header information is short. <P>SOLUTION: In a receiver for receiving a periodic signal whose frame period is unknown, a frame length detector employs the AR model estimate method to detect the frame length. That is, the frame length detector segments data of a detection object, calculates coefficients äai} in the AR model and thereafter calculates a summed average AVsi (=si/N) (steps S2 to S5). Finally, the summed average results AVsi are arranged for detecting the peak and the peak period is obtained (step S6). The peak period obtained in this way can be detected as a period of a UW, that is a header, and this corresponds to the frame period. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
