Spurious-free dynamic range improvement in a photonic time-stretched analog-to-digital converter based on third-order predistortion

Spurious-free dynamic range (SFDR) limited by intermodulation distortions is a usually accepted measure for dynamic performance of a photonic time-stretched analog-to-digital converter (ADC). In this paper, SFDR improvement in a photonic time-stretched ADC based on third-order predistortion is proposed. The third-order predistortion is achieved optically within an integrated dual-parallel Mach–Zehnder modulator (DPMZM). The mechanism of SFDR improvement with third-order predistortion in the DPMZM is theoretically analyzed. Compared with a conventional scheme without predistortion, the experimental results show that the SFDR improvement of ∼26  dB in the proposed scheme is proved. [Publisher's Note: This paper is part of the Microwave Photonics special issue published in Photonics Research, Vol. 2, No. 4. It was mistakenly published in Issue No. 5.]