Experimental Study on a 4-b Serial Optical Digital to Analog Convertor

Photonic techniques have potential to overcome the limitations of electronic digital-to-analog conversion. A serial optical DAC, using fiber dispersion with optical weighted wavelength multiplexing, is proposed and demonstrated. Serial Digital codes are overlapped regularly in time domain due to dispersion-based delays. Intensity information for the conversion is extracted by synchronous gating pulse train. The system is operated with a high precision time control. Performance of the ODAC is experimentally investigated by establishing a 4-b 12.5 Gb/s system. The linear transfer function is described and an ENOB of 3.55 is obtained. The proposed architecture could be easily modified for better performance.