This paper proved that a frequency stochastic sequence obtained from a stationarily correlated time series by using discrete Fourier transform is orthogonal.

本文证明了时间域内的平稳相关序列经离散傅里叶变换之后，听得到的是频域内的正交随机序列。

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This paper describes the need to transform the continuous periodic signal in time domain to the discrete signal in frequency domain by using Fourier Series (FS).

讨论了利用傅里叶级数把连续周期时域信号转换成离散的频域信号的必要性。

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