Share Email Print

Proceedings Paper

Ultrawideband wide-open RF spectrum analysis using spectral hole burning
Author(s): Max Colice; Friso Schlottau; Kelvin Wagner
Format Member Price Non-Member Price
PDF $14.40 $18.00
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

We propose performing ultrawideband RF spectrum analysis using spectral-hole-burning (SHB) crystals, which are crystal hosts lightly doped with rare earth ions such as Tm3+ or Er3+. Cooling SHB crystals to cryogenic temperatures suppresses phonon broadening, narrowing the ions' homogeneous linewidths to <100 kHz; local inhomogeneities in the crystal lattice shift the individual ionic resonances such that they're distributed over a bandwidth of 20 GHz or in some structurally disordered crystals to up to 200 GHz. Illuminating an SHB crystal with a beam modulated with multiple RF sidebands digs spectral holes in the crystal's absorption profile that persist for the excited state lifetime, about 10 ms. The spectral holes are a negative image of the modulated beam's spectrum. We can determine the location of these spectral holes by probing the crystal with a chirped laser and measuring the transmitted intensity. The transmitted intensity is the double-sideband spectrum of the original illumination blurred by a 100 kHz Lorentzian and mapped into a time-varying signal. Scaling the time series associated with the transmitted intensity by the instantaneous chirp rate yields the spectrum of the original illumination. Postprocessing algorithms undo distortion due to swept laser nonuniformities and ringing induced by fast chirp beams, eliminating the need for long dwell times to resolve narrow spectral features. Because the read and write processes occur simultaneously, SHB spectrum analyzers can operate with unity probability of intercept over a bandwidth limited only by the inhomogeneous linewidth. These capabilities make SHB spectrum analyzers attractive alternates to other approaches to wideband spectrum analysis.

Paper Details

Date Published: 5 October 2005
PDF: 10 pages
Proc. SPIE 5971, Photonic Applications in Nonlinear Optics, Nanophotonics, and Microwave Photonics, 597128 (5 October 2005); doi: 10.1117/12.628844
Show Author Affiliations
Max Colice, Univ. of Colorado at Boulder (United States)
Friso Schlottau, Univ. of Colorado at Boulder (United States)
Kelvin Wagner, Univ. of Colorado at Boulder (United States)

Published in SPIE Proceedings Vol. 5971:
Photonic Applications in Nonlinear Optics, Nanophotonics, and Microwave Photonics
Roberto A. Morandotti; Harry E. Ruda; Jianping Yao, Editor(s)

© SPIE. Terms of Use
Back to Top