학술논문

High Rejection and Frequency Agile Optical Filtering of RF Signals Using a Rare Earth Ion-Doped Crystal
Document Type
Periodical
Source
Journal of Lightwave Technology J. Lightwave Technol. Lightwave Technology, Journal of. 40(20):6901-6910 Oct, 2022
Subject
Communication, Networking and Broadcast Technologies
Photonics and Electrooptics
Radio frequency
Optical filters
Laser beams
Crystals
Optical diffraction
Bandwidth
RF signals
Filtering
microwave photonics
rare-earth ion-doped crystals
spectral hole burning
Language
ISSN
0733-8724
1558-2213
Abstract
While photonics is broadly considered as a leading solution for analog RF processing, photonic RF filters often show a limited out-of-band rejection. In this work we demonstrate a high rejection and high steepness photonic RF bandpass filter based on spectral hole burning in a rare earth ion-doped crystal. The filter is obtained by programming a frequency-selective absorption grating in the crystal. With an experimental and theoretical study we identify the optimal parameters for this filter. We achieve a remarkable rejection of 60 dB and a rejection of 45 dB at 50 MHz from the edge of the filter, compliant with most demanding applications.