matlab通带滤波，是在频域内实现的，最好用于地震波，或其他一些信号逐渐衰减的情况-bandpass filter,used for strong motion data process for better. because the software carry out the filter function through fft

信号分析系统，用于对各种信号进行各种时域、频域、时频分析，此仿真软件方便快捷。-Signal analysis system, used for the analysis of all kinds of time domain, frequency domain, time-frequency signals of various kinds, this simulation software, convenient and quick.

对信号进行离散傅里叶变换，将信号从时域变换到频域进行分析-Discrete Fourier transform of the signal, the signal the time domain to the frequency domain analysis