A Bayesian approach to electric field and E-region neutral wind estimation with the poker flat advanced modular incoherent scatter radar

In this paper, we describe an approach for computing vector electric fields in the F region and neutral winds in the E region from incoherent scatter radar (ISR) measurements, applicable especially for Advanced Modular Incoherent Scatter Radar (AMISR) systems, namely, the Poker Flat Incoherent Scatter Radar (PFISR). PFISR is a 128-panel (upgraded from 96 panels in September 2007) AMISR system installed at the Poker Flat Research Range near Fairbanks, Alaska. The pulse-to-pulse steering capabilities of AMISR support the measurement of line-of-sight velocities in multiple look directions essentially simultaneously. This capability in turn allows electric fields and neutral winds to be resolved with minimal assumptions regarding time stationarity of the medium. The multibeamforming capability also allows additional flexibility in the estimation of those parameters, for which experiment planning can become very important. The approach described herein is ideally suited for such planning, is appropriate for the overdetermined problem characteristic of AMISR measurements, and allows in a simple way for the inclusion of appropriate a priori information such as the assumption of negligible parallel electric fields and negligible vertical neutral winds. We present some case studies from the PFISR that demonstrate some of the new capabilities.