Cascade Optical Quantization Scheme for Efficient Resolution Enhancement of All-optical ADC
A novel cascade optical quantization scheme for the resolution enhancement of all-optical ADC is proposed. Using a phase modulator embedded Sagnac loop and the array of splitters with specific splitting ratios, the cascade optical quantization is realized with the maximum 1.59-bit enhancement of stated-number-of-bits. Simulation results show that a 20 GHz RF signal is precisely digitalized with the spur-free dynamic range of 30.18 dBc and effective-number-of-bits of 4.22-bit.