THE RADIATION IMPEDANCE OF ORBITING CONDUCTORS

The dispersion relation for waves in a cold, magnetized plasma is disc ussed using the potential for the longitudinal part of the electric fi eld. This clarifies wave emission from a conductor in low Earth orbit and should be useful in considering the far field and both hot plasma and nonlinear, near-field effects. General formulas for radiation impe dance are directly obtained. For tethers a fundamental dependence on c ontactor size is discussed. Spherical and ellipsoidal contactors and a n (anodeless) bare tether are considered. Simple arguments on nonlinea r contactor effects lead to a surprisingly simple result for impedance s off the Alfven branch.