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Consider two x-polarized waves that counter-propagate along the z axis. The wave traveling in the forward z direction is of frequency ω1; the backward z propagating wave is at frequency ω 1, where ω < ω1. Both frequencies are very slightly detuned on either side of their mean frequency, ω 0: such that ω0 - ω1 = ω1 – ω0 <<1. Using the complex field forms, construct the expression for the total electric field, and from this, find the power density distribution (proportional to EE* ). Your answer should be in the form of a '’standing wave" that in fact moves slowly along the z axis. Find an expression for the velocity of the wave pattern in terms of given or known parameters. Does the pattern move in the forward or backward z direction?
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Engineering Electromagnetics
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