A review of plasma based frequency shifting methods

Summary form only given. An extensive study of shifting the frequency of a propagating RF signal using a pulsed plasma discharge has been made. In the experimental work, two frequency shifting mechanisms have been used. The first uses the plasma as an nonphysical plunger to upshift the frequency of the signal. Using this method, one routinely observes frequency shifts of 0.2% from the original signal. The authors have done extensive computer models of this method using the MRC magic code and obtained good agreement with the experimental results. The second method uses the phase velocity increase of a plasma growing in density to change the frequency of the incoming radiation. Using this method, frequency shifts of 50 MHz have been observed for a 2.68 GHz signal. It was found analytically that, for a large-scale model, the frequency shift scales linearly with transit time.