Integrated Lithium Niobate Acousto-optic Frequency Shifter

Shao, Linbo; Sinclair, Neil; Leatham, James; Hu, Yaowen; Yu, Mengjie; Turpin, Terry M.; Crowe, Devon G.; Lončar, Marko

doi:10.1364/cleo_si.2020.sth1f.5

Cited by 7 publications

(6 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The benchtop EDFA can be replaced with a compact EDFA (such as ACL-PM-mini-EDFA-24) that can offer sufficient gain to offset the in-loop losses. On-chip components, such as AOM [48], [49], bandpass filter [50], and waveguide amplifier [51], are also promising to reduce the optical system's size further. A commercial data acquisition (DAQ) unit could be sufficient to simultaneously generate the RF driving signal and acquire the demodulated signal, therefore minimizing the system's electronic footprint.…”

Section: Discussionmentioning

confidence: 99%

Photonic Generation of 30 GHz Bandwidth Stepped-Frequency Signals for Radar Applications

Zhang

Liu

Eggleton

2022

J. Lightwave Technol.

View full text Add to dashboard Cite

Wideband microwave signals with high timefrequency linearity for high-resolution radar applications can be optically generated using high-speed electronic waveform generators. Frequency-shifting modulation in an optical cavity provides an attractive approach to generate broadband microwave signals with reduced complexity requiring only MHz-level electronics. However, the in-loop signal instability and inter-pulse interference usually cause amplitude fluctuations, leading to limited signal-to-noise ratio and signal bandwidth. Here, we overcome these challenges and demonstrate, for the first time, the photonic generation of 30-GHz-wide stepped-frequency (SF) signals with 100 MHz frequency steps defined by an MHz-level electrical oscillator. We achieved this performance by mitigating the in-loop polarization scrambling and inter-pulse interference using a polarization-maintaining cavity and a high-extinction optical switch. This allows stable consecutive acousto-optic frequency-shifting modulation that significantly improves the signal-to-noise ratio. While achieving a bandwidth surpassing the state-of-the-art demonstrations based on wideband electronics, our approach alleviates the necessity for high-speed signal generators or wideband tunable lasers. To exemplify the utility, we systematically evaluate the signal quality and show its applications in radar imaging compared to those using electrical waveform generators.

show abstract

Section: Discussionmentioning

confidence: 99%

Photonic Generation of 30 GHz Bandwidth Stepped-Frequency Signals for Radar Applications

Zhang

Liu

Eggleton

2022

J. Lightwave Technol.

View full text Add to dashboard Cite

show abstract

“…Thus, multiple sensors, enabled by one centralized photonic system, can seamlessly work together without interference to achieve broader detection coverage with lower overall complexity and cost. In terms of future developments towards the miniaturization of photonic systems, recent advances in the photonic integration of critical function building blocks, such as on-chip AOFSs 57,58 and optical waveguide amplifiers 59,60 , are providing a promising technical basis with which to achieve compact size for portable sensing 31,53 . This photonic approach offers a new path towards high-resolution, rapid-response and cost-effective hybrid radar-LiDAR modules for distributed, contactless vital sign detection.…”

Section: Articlementioning

confidence: 99%

Photonic radar for contactless vital sign detection

Zhang

Liu

Stephens³

et al. 2023

Nat. Photon.

View full text Add to dashboard Cite

Vital sign detection is used across ubiquitous scenarios in medical and health settings, and contact and wearable sensors have been widely deployed. However, they are unsuitable for patients with burn wounds or infants with insufficient areas for attachment. Contactless detection can be achieved using camera imaging, but it is susceptible to ambient light conditions and has privacy concerns. Here we report a photonic radar for non-contact vital sign detection to overcome these challenges. This photonic radar can achieve millimetre-level range resolution based on synthesized radar signals with a bandwidth of up to 30 GHz. The high resolution of the radar system enables accurate respiratory detection from breathing simulators and a cane toad as a human proxy. Moreover, we demonstrate that the optical signals generated from the proposed system can enable vital sign detection based on light detection and ranging (LiDAR). This demonstration reveals the potential of a sensor-fusion architecture that can combine the complementary features of radar and LiDAR to achieve improved sensing accuracy and system resilience. The work provides a technical basis for contactless and high-resolution vital sign detection to meet the increasing demands of future medical and healthcare applications.

show abstract

“…As this work presented a broad bandwidth operation, the fabrication process is difficult and still exotic. In [8], a PIC was fabricated using a thin film of Lithium Niobate, and the acousto-optic effect was applied to achieve a 3 GHz frequency shift with a 30 dB carrier suppression. However, this work is still not compatible with current foundry fabrication standards.…”

Section: Introductionmentioning

confidence: 99%

Photonic Integrated Frequency Shifter Based on Double Side Band Modulation: Performance Analysis

2022

View full text Add to dashboard Cite

In this research, we present an analysis of a photonic integrated frequency shifter as a stage for a THz dual comb generator. We studied the performance of the PIC by simulating it with standard building blocks, and aimed toward an improvement of the output signal quality. We revised two approaches of the PIC by simulating two modes of generating a double side band modulation suppressed carrier (DSB-SC) with a Mach Zehnder modulator structure (MZM). One approach was using a single Electro-Optic Phase Modulator (EOPM) on an MZM structure (SE-MZM), and the other one was using Double EOPM (DE-MZM). We found a cleaner spectrum with the DE-MZM, since this structure is usually applied to reduce the chirp effect in optical communication systems. We obtained 23 dB of side mode suppression ratio SMSR with one filter, and 44 dB of SMSR with a two-stage filter. In the case of DE-MZM, we obtained a clean tone on intermediate frequency (IF) free of spurious sidebands and comb in IF frequency with 10 dB more power compared to SE-MZM.

show abstract

Integrated Lithium Niobate Acousto-optic Frequency Shifter

Abstract: We demonstrate a 3-GHz acousto-optic frequency shifter on a thin-film lithium niobate platform, featuring over 30 dB carrier suppression. The active frequency shifting loop generates a frequency comb with 200 lines over 5 nm optical bandwidth.

Cited by 7 publications

References 8 publications

Photonic Generation of 30 GHz Bandwidth Stepped-Frequency Signals for Radar Applications

Photonic Generation of 30 GHz Bandwidth Stepped-Frequency Signals for Radar Applications

Photonic radar for contactless vital sign detection

Photonic Integrated Frequency Shifter Based on Double Side Band Modulation: Performance Analysis

Contact Info

Product

Resources

About