Shoichiro Oda

All-optical quantization scheme based on fiber nonlinearity

We have proposed a novel all-optical quantization scheme that may be useful for analog-to-digital conversion. The preprocess of optical sampling is performed by four-wave mixing, and optical quantizing is realized by soliton phenomena. We have conducted a simple proof-of-principle experiment, and demonstrated the optical multilevel thresholding to show the feasibility of the proposed method.

All-optical digital-to-analog conversion using nonlinear optical loop mirrors

We propose a novel ultrafast all-optical digital-to-analog conversion (DAC) scheme consisting of nonlinear optical loop mirrors, which can be applied to both a standard binary code and a Gray code. We conducted a proof-of-principle experiment and successfully demonstrated a 2-bit all-optical DAC with a Gray code, which indicates that the proposed scheme is feasible.

Two-bit all-optical analog-to-digital conversion by filtering broadened and split spectrum induced by soliton effect or self-phase modulation in fiber

The Kerr effect in fiber is expected to play a major role in ultrafast all-optical signal processing, which can overcome the obstacles of inherently limited operating speed of electronic devices. In this paper, we propose novel ultrafast and polarization-independent all-optical analog-to-digital conversion schemes. The proposed schemes are realized by filtering the broadened and split spectrum induced by the soliton effect or self-phase modulation in fiber with an arrayed waveguide grating. We conducted proof-of-principle experiments and successfully demonstrated two-bit all-optical analog-to-digital conversions with Gray code output, which shows the feasibility of the proposed scheme.

All-optical tunable delay line based on soliton self-frequency shift and filtering broadened spectrum due to self-phase modulation

We propose a novel all-optical tunable delay line based on soliton self-frequency shift and filtering broadened spectrum due to self-phase modulation to compensate for the frequency shift. We experimentally demonstrate the proposed all-optical tunable delay line and achieve a continuous temporal shift up to 19.2 ps for 0.5 ps pulse, corresponding to a delay-to-pulse-width ratio of 38.4.

2-Bit All-Optical Analog-to-Digital Conversion by Slicing Supercontinuum Spectrum and Switching with Nonlinear Optical Loop Mirror and Its Application to Quaternary ASK-to-OOK Modulation Format Converter

Recently, the research on all-optical analog-to-digital conversion (ADC) has been extensively attempted to break through inherently limited operating speed of electronic devices. In this paper, we describe a novel quantization scheme by slicing supercontinuum (SC) spectrum for all-optical ADC and then propose a 2-bit all-optical ADC scheme consisting of the quantization by slicing SC spectrum and the coding by switching pulses with a nonlinear optical loop mirror (NOLM). The feasibility of the proposed quantization scheme was confirmed by numerical simulation:.We conducted proof-of-principle experiments of optical quantization by slicing SC spectrum with an arrayed waveguide grating and optical coding by switching pulses with NOLM. We successfully demonstrated optical quantization and coding, which allows us to confirm the feasibility of the proposed 2-bit ADC scheme.

All-optical analog-to-cligital conversion by slicing supercontinuum spectrum and switching with nonlinear optical loop mirror

We propose a novel all-optical analog-to-digital conversion scheme consisting of quantization by slicing supercontinuum spectrum and coding by switching pulses with a nonlinear optical loop mirror. The proposed scheme is experimentally demonstrated.

All-optical analog-to-digital conversion utilizing nonlinear phenomena in fiber

A novel all-optical analog-to-digital conversion scheme including both sampling and quantizing is proposed. It is based on nonlinear phenomena in optical fiber, i.e. four-wave mixing is used for sampling and soliton phenomena for quantizing. An experiment on separating higher order solitons is conducted.

Optical Signal Processing Based on All-Optical Analog-to-Digital Conversion

The nonlinearity of optical fiber provides attractive functionalities for all-optical signal processing. Recently, researchers have extensively studied all-optical analog-to-digital and digital-to-analog converters in an effort to surpass the inherently limited operating speed of these devices’ electronic counterparts.

optical Signial Processing based on All-Optical Analog-to-Digital Conversion

Fiber nonlinearities provide us attractive functions for optical signal processing. In this paper, we focus our attention on all-optical analog-to-digital and digital-to-analog conversion schemes which can be applied for wide variety of signal processing.

Photonic Analog-to-Digital Conversion Using Electro-Absorption Modulator and Supercontinuum Light

We propose a novel photonic analog-to-digital conversion scheme using electro-absorption modulator and supercontinuum light. In this paper, a 2-bit photonic analog-to-digital conversion is experimentally demonstrated using an arrayed waveguide grating.