Transient signal propagation in lossless, isotropic plasmas

Abstract

The concept of the wave packet is used to obtain some general results on the propagation of signals in dispersive media. The dispersion of a Gaussian carrier pulse and a square wave carrier pulse in an isotropic plasma is carried out using the wave packet concept. A general analysis of transient wave propagation in isotropic plasmias is given using Laplace transform methods. Solutions are given in terms of series solutions which may be expressed in terms of Lornmel functions. Integral solutions which can be ear.-ly evaluated numerically are derived using the convolution theorem arid using contour integration techniques. The solutions are useful for sk.ort dispervion lengths. Mir Illustrations 4. P:ilse Definition of Two Gaussian Pulses 5. Regions of Good Pulse Definition and No Pulse Definition 6. Propagation of a Sine Wave Electric Field in an Overdense Plasma 7. Envelope Response for the Propagation of a Sine Wave Electric Field with a Finite Rise Time 8. Propagation of a Step Function Electric Field in a Plasma 9. The Complex Frequency Plane 10. The Complex Frequency Plane for a Branch Cut from-ill to +inl 11. The Sign Distribution on Each Riemann Shee'. for the Branch Cut of Figure 10 12. The Contour for the Branch Cut in Figure 10 13. The Contour for Branch Cuts in the Left Half Frequency Plane 14. The Amplitude of the Transient Envelope 15. The Total Transient Solution Obtained by Integration Along the Branch Cuts 16. The Total Solution of a Propagating Sine Wave Electric Field vi Transient Signal Propagation in Lossless, Isotropic Plasmas Volume I s,.l,,t,'tel s4o thati nil st'r-urit'' cla-6ssifte-iti:1 Is, regquiet. tl. ~ldmti. O9t. OTIIERl REPORTl NIIMIERS). if tile report has beetn fir.st seopsn te isga ritrd'nemmii ass ipr. ,d any other reltcrti numbers (ether. c by rt'e mriginauttor lacty Intuir'.t toni' riamr', feogrueph in: loviithit, may Il.btin' k~epta or y he p~~or, ls !-ie ths umhr().k-'y worols% but will be fr1 lorwt'd iry an inI icat ion tof t c':miica I or 'v it'.rpaso). lsontr tis umier~). o;It'xt. Till' anisignes'ent-if links. rolt's, andl(weighti is I eopt ionn I. Unclassified S-'curitv Clai S i (caitl m i

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“…19 when it achieved at a frequency CO= =f radians. Fig.3 The order variance increase for the old stock policy…”

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