| 摘要 |
PURPOSE: To provide a diagnosing method with high accuracy by detecting the time of a sampled living body signal at the maximal point sequentially and finding the fluctuation of a heartbeat interval by dividing a time sequentially by a basic time decided in advance and performing spectrum analysis on the heartbeat interval by a linear predicting method using an autoregressive model. CONSTITUTION: A living body analog signal is inputted to a peak detection circuit 12 which finds an interval between a certain heartbeat and the next heartbeat sequentially, and detects the time T1 -Tn at the maximal point, then, the intervals P1 -Pn (n: positive integer) of the heartbeat can be formed by dividing the period between a certain time and the next time sequentially by a basic clock decided in advance and sent out from a clock circuit 13. In other words, assuming the basic clock as TCLK, relation Pn =(Tn -Tn-1 )/TCLK is established. The heartbeat interval is counted by a counter 14, and it is stored in a RAM 15 at every detection of the time at the maximal point. The content of the RAM 15 is inputted to a DSP 16, and the spectrum analysis is performed on it by the linear predicting method using the autoregressive model. |
