title: Resolution-enhanced all-optical analog-to-digital converter employing cascade optical quantization operation.
abstract: In this paper, a cascade optical quantization scheme is proposed to realize all-optical analog-to-digital converter with efficiently enhanced quantization resolution and achievable high analog bandwidth of larger than 20 GHz. Employing the cascade structure of an unbalanced Mach-zehnder modulator and a specially designed optical directional coupler, we predict the enhancement of number-of-bits can be up to 1.59-bit. Simulation results show that a 25 GHz RF signal is efficiently digitalized with the signal-to-noise ratio of 33.58 dB and effective-number-of-bits of 5.28-bit.
authors.forename: Zhe
authors.initials: Z
authors.lastname: Kang
authors.forename: Xianting
authors.initials: X
authors.lastname: Zhang
authors.forename: Jinhui
authors.initials: J
authors.lastname: Yuan
authors.forename: Xinzhu
authors.initials: X
authors.lastname: Sang
authors.forename: Qiang
authors.initials: Q
authors.lastname: Wu
authors.forename: Gerald
authors.initials: G
authors.lastname: Farrell
authors.forename: Chongxiu
authors.initials: C
authors.lastname: Yu