Chromatic dispersion compensation using two pilot tones in optical OFDM systems

We propose a novel approach to compensate the fiber chromatic dispersion (CD) and to adjust the phase/amplitude using two pilot tones in fiber optical OFDM transmission. In the conventional channel estimation methods, one or more symbols have to be applied as the pilot tones. The new approach makes full use of the fiber CD properties while using less pilot tones. The simulations show a significant improvement (~ 2 dB) of the optical OFDM signal in terms of the bit error rate (BER) penalty, compared with the conventional least-square (LS) linear interpolation and one-reference-symbol methods.