Toward an optimum receiving array and pulse set for the Dynasonde
The accuracy and efficiency with which radio echo parameters may be estimated by a programmable ionosonde of high resolution depend upon software-designed strategies of pulse set design and receiving antenna layout. All of the echo parameters, except amplitude and time of arrival (thus three components of echolocation, Doppler, polarization rotation, and an average phase angle) are determined by phase angle differences. The solution is conveniently expressed as a least squares estimation, provided that more than six independent phase measurements are available. Since the observed phases are necessarily obtained modulo 360°, from 12-bit complex amplitude data, each parameter is subject to aliasing ambiguities which must be anticipated in each strategy, and minimized.