CO-OFDM (COherent light-Orthogonal Frequency Division Multiplexing) system channel estimation method based on channel impulse response filtering

The invention provides a CO-OFDM (COherent light-Orthogonal Frequency Division Multiplexing) system channel estimation method based on channel impulse response filtering, which can improve the noise resistance capability for channel estimation with smaller system expenditure. The method comprises the following steps of: carrying out IFFT (Inverse Fast Fourier Transform) transform on a channel transfer function estimated by an LS (Least Square) channel to obtain a channel impulse response; calculating the length of the channel impulse response according to optical fiber channel parameters, such as dispersion, polarization mode dispersion and the like; constructing a Blackman window function according to the length of the channel impulse response; carrying out time domain multiplication on the channel impulse response and the Blackman window function; carrying out FFT transform on the processed channel impulse response to obtain a channel transfer function of which the noise is filtered out ...