A novel training symbol structure design for transmitter IQ mismatch estimation and compensation in CO-OFDM system

In this paper, a new training symbol structure consists of two adjacent training symbols is proposed to estimate transmitter in-phase/quadrature(IQ) mismatch and channel information in coherent optical orthogonal frequency division multiplexing (CO-OFDM) system. Each training symbol of the proposed scheme has two subsets which are mirror images of each other, and one subset values are set to zeros. Simulation in high speed gives the results that proved the proposed scheme increased the system performance.