Signal processing in a nonperiodically time-varying magnetoelastic medium
- 1 March 1968
- journal article
- Published by Institute of Electrical and Electronics Engineers (IEEE) in Proceedings of the IEEE
- Vol. 56 (3) , 258-272
- https://doi.org/10.1109/proc.1968.6270
Abstract
Wave propagation in a nonperiodically time-varying medium provides a means for realizing in simple physical structures a variety of signal-processing operations, such as frequency translation and coding, variable delay recall, gating, time-scale stretching or shrinking, and time reversal. The use of low-velocity modes, such as acoustic, spin, or magnetoelastic waves in solids, reduces the length of the propagation structure required to less than an inch. A general review is given of the principles of wave propagation in a spatially uniform medium with nonperiodic time variation. Both abrupt and gradual time variations are discussed. Illustrations are given for the cases of spin-wave and magnetoelastic-wave propagation and signal processing operations in these media are explained. Consideration is given to the problem of spin-wave propagation in a time-and space-varying magnetic field of the form encountered in experiments; and it is shown that a simple separated variable solution exists. For the more difficult problem of magnetoelastic propagation with both space and time variations, an approximate space-time ray theory is described. Experimental results for pulsed-field processing of spin and magnetoelastic waves are given and related to the theory.Keywords
This publication has 25 references indexed in Scilit:
- Theoretical considerations of time delay for bias-field pulsing in y.i.g.Electronics Letters, 1967
- DOPPLER CONVERSION AND ADIABATIC TIME DOMAIN CONVERSION OF ACOUSTIC AND SPIN WAVESApplied Physics Letters, 1966
- Transformation and reversal of time scale by a time-varying transmission lineElectronics Letters, 1966
- Phase-Velocity-Modulated Magnetoelastic WavesJournal of Applied Physics, 1966
- Signal processing with a time-varying transmission linePublished by Institute of Electrical and Electronics Engineers (IEEE) ,1966
- Ultrawide bandwidth pulse compression in YIGProceedings of the IEEE, 1966
- Microwave pulse compression utilising an yttrium-iron-garnet delay lineElectronics Letters, 1965
- Linear Signal Stretching in a Time-Variant SystemIEEE Transactions on Circuit Theory, 1965
- Elastic and magnetoelastic waves in yttrium iron garnetProceedings of the IEEE, 1965
- Velocity Modulation of Propagating WavesJournal of Applied Physics, 1963