Experimental Demonstration of All-Optical Analog-to-Digital Conversion With Balanced Detection Threshold Scheme

A novel balanced detection threshold scheme for all-optical analog-to-digital conversion is experimentally demonstrated. A 4-bit 10-GSamples/s all-optical analog-to-digital converter based on phase-shifted optical quantization and a balanced detection threshold scheme is realized to quantize a 9.9-GHz sinusoidal electrical signal, achieving a spur-free dynamic range of 24.2 dB. Compared with single-ended detection, the quantization result is improved with the balanced threshold scheme due to reducing the influence of the power fluctuation and improving the receiver sensitivity.