Vol. 24, No. 21 | 17 Oct 2016 | OPTICS EXPRESS 24061 Compensation of multi-channel mismatches in high-speed high-resolution photonic analog- to-digital converter * GUANG YANG, WEIWEN ZOU, LEI YU, KAN WU, AND JIANPING CHEN State Key Laboratory of Advanced Optical Communication Systems and Networks, Department of Electronic Engineering, Shanghai Jiao Tong University, Shanghai 200240, China *[email protected] Abstract: We demonstrate a method to compensate multi-channel mismatches that intrinsically exist in a photonic analog-to-digital converter (ADC) system. This system, nominated time-wavelength interleaved photonic ADC (TWI-PADC), is time-interleaved via wavelength demultiplexing/multiplexing before photonic sampling, wavelength demultiplexing channelization, and electronic quantization. Mismatches among multiple channels are estimated in frequency domain and hardware adjustment are used to approach the device-limited accuracy. A multi-channel mismatch compensation algorithm, inspired from the time-interleaved electronic ADC, is developed to effectively improve the performance of TWI-PADC. In the experiment, we configure out a 4-channel TWI-PADC system with 40 GS/s sampling rate based on a 10-GHz actively mode-locked fiber laser. After multi-channel mismatch compensation, the effective number of bit (ENOB) of the 40-GS/s TWI-PADC system is enhanced from ~6 bits to >8.5 bits when the RF frequency is within 0.1-3.1 GHz and from ~6 bits to >7.5 bits within 3.1-12.1 GHz. The enhanced performance of the TWI-PADC system approaches the limitation determined by the timing jitter and noise. © 2016 Optical Society of America OCIS codes: (060.5625) Radio frequency photonics; (230.0250) Optoelectronics; (250.4745) Optical processing devices; (000.4430) Numerical approximation and analysis. References and links 1. H. F. Taylor, “An optical analog-to-digital converter-design and analysis,” IEEE J. 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In this PADC [2,3], a stable pulsed laser works as a sampling source [8], an optical modulator serves as a sampling gate for RF signal, and an array of photo-detectors (PDs) is employed to convert the sampled optical signal to the sampled electronic signal that is electronically quantized by an Vol. 24, No. 21 | 17 Oct 2016 | OPTICS EXPRESS 24063 array of EADCs.