Updating the full-profile incoherent scatter analysis at Jicamarca

Abstract

A full-profile incoherent scatter analysis, in which all ionospheric state variables at all altitudes are estimated simultaneously, has been implemented at Jicamarca for topside research. Such an analysis is particularly expedient at Jicamarca where the correlation time of the 50-MHz echoes is long. Long pulses are interleaved with short double pulses which provide complementary measurements at altitudes below and near the F peak. Absolute number density calibration is performed by exploiting Faraday rotation. We compute range-lag ambiguity functions for lag profile forward modeling in a general way. Autocorrelation function calculations take into account the small magnetic aspect angles of Jicamarca observations. Regularization is used to confine the solution space of the analysis and confer stability. A grid search provides the initial state for the iterative method we use. The overall algorithm can be made to run in real time on a single i7 processor core. Representative data are used to demonstrate the efficacy of the algorithm.