Broadband linearization in photonic time-stretch analog-to-digital converters employing an asymmetrical dual-parallel Mach-Zehnder modulator and a balanced detector

Abstract

A broadband linearization scheme for time-stretch analog-to-digital converters (TS-ADCs) is proposed based on an asymmetrical dual-parallel Mach-Zehnder modulator and a balanced detector. The theoretical and simulation results indicate that, compared with the differential and arcsine operation method generally employed in TS-ADCs, the proposed scheme has a superior performance on enhancing the spur-free dynamic range and suppressing the even-order distortions and the third-order spurs even under a large modulation depth. Additionally, the proposed scheme realizes online linearization. Therefore, it has the potential to enhance the dynamic range of a broadband TS-ADC in real time.