Integrated waveguide Bragg gratings for microwave photonics signal processing

Abstract

Integrated Microwave photonics (IMWP) signal processing using Photonic Integrated Circuits (PICs) has attracted a great deal of attention in recent years as an enabling technology for a number of functionalities not attainable by purely microwave solutions. In this context, integrated waveguide Bragg grating (WBG) devices constitute a particularly attractive approach thanks to their compactness and flexibility in producing arbitrarily defined amplitude and phase responses, by directly acting on coupling coefficient and perturbations of the grating profile. In this article, we review recent advances in the field of integrated WBGs applied to MWP, analyzing the advantages leveraged by an integrated realization. We provide a perspective on the exciting possibilities offered by the silicon photonics platform in the field of MWP, potentially enabling integration of highly-complex active and passive functionalities with high yield on a single chip, with a particular focus on the use of WBGs as basic building blocks for linear filtering operations. We demonstrate the versatility of WBG-based devices by proposing and experimentally demonstrating a novel, continuously-tunable, integrated true-time-delay (TTD) line based on a very simple dual phase-shifted WBG (DPS-WBG).

Simultaneous Multi-Channel Microwave Photonic Signal Processing

“…In particular, high performance AWGs in SiP [36] have been realized and BGs are now routinely produced [37,38]. By introducing a pn junction to the silicon waveguide and applying a bias voltage, reconfiguration can be enabled through the plasma dispersion effect.…”

Silicon photonic Bragg-grating couplers for optical communications

“…38 High-Q resonators in phase-shifted (PS) Bragg gratings with measured Q factor of up to 1 × 10 5 were demonstrated. Photonic resonators with add-drop operation are desired for integrated applications to avoid use of on-chip isolators.…”

Recent progresses on optical arbitrary waveform generation

“…The state-of-the-art digital electronics has a very limited sampling speed due to its narrow signal processing bandwidth, the sampling rate of currently available arbitrary waveform generation (AWG) systems based on electronics technologies is limited to about 50 Gb/s. Thanks to the inherent high-speed and broad bandwidth offered by rapidly developed optical techniques, the photonic-assisted generation of ultrafast arbitrary optical/microwave waveforms in the optical domain has been a hot topic of interest in the past few years [32][33][34][35][36][37][38][39][40].…”

“…Over the decades, many kinds of optical techniques from free-space-based [4], fiber-based [34] to integrated optics [40] have been proposed to generate wideband and ultrafast optical/microwave waveforms. Microwave waveform is in general generated in the optical domain and then converted into microwave waveform with optical-toelectrical conversion in a photodetector (PD).…”