| 摘要 |
PURPOSE:To reduce the memory capacity, by converting a compiling data to a function by use of Fourier conversion, and storing it as a function. CONSTITUTION:An original data X(t) is A/D converted at each data which is brought to sampling, and thereafter, is stored in a built-in memory. After compiling of all data ended, the compiled data is Fourier-converted by a high speed Fourier conversion FFT10, and magnitude of a constant part, frequency and a component of a real part and a virtual part of complex display is calculated. As for the Fourier-converted data, the component being below a limiter level is cut by a power spectrum limiter 11. These power spectrum components are fetched successively from that which has a large contribution rate, by a reloaded data processor 12, and are Fourier reverse-converted by a reverse Fourier conversion IFT13. As a result, a multinominal expression of n-order (n is an integer) is reproduced as a reloaded data X'(t). A digital processor stores only a coefficient of the multinominal expression in a data memory. In this way, the memory capacity can be reduced. |
