Abstract
This paper presents a novel diversity and absolute combining time domain transmitter (DACTDT) for the Enhanced Asymmetrically and Symmetrically Clipped Optical (EASCO) OFDM system. This system estimates and eliminates the clipping distortion of the signal at the transmitter. The spectral efficiency and bit-error-rate (BER) were improved. The DACTDT effectively combines time domain diversity combining technique (TDDT)-applied to ACO-OFDM stream and the novel absolute combining time domain technique (ACTDT)-applied to ESCO-OFDM stream. Both TDDT and the proposed ACTDT utilize the clipping distortion of their respective streams to improve their performance. In terms of Optical Signal-to-Noise Ratio (OSNR), at a BER of 10(-3) with 1024-QAM, the proposed EASCO-DACTDT OFDM performs 8.3 dB better than EASCO-OFDM.