Retrieval of Venus' Ionospheric Profile from Radio Science Experiment Onboard Akatsuki

We retrieved the Venusian Ionospheric profiles from the Radio Science Experiment onboard Akatsuki spacecraft of JAXA, also known as Venus Climate Orbiter (VCO). A 8.4 GHz downlink radio signal transmitted from the Ultra Stable Oscillator (USO) onboard the spacecraft is received at the 32 m antenna at Indian Deep Space Network (IDSN), Byalalu. The received signal is heterodyned and sampled at the ground station and further digitized as data packets is used to apply a retrieval algorithm to estimate the frequency shift due to path delay experienced by the traveling radio ray while passing through the ionospheric and atmospheric medium of Venus. A peak electron number density of 2-4.5 ~m-3 is observed at V2 layer (∼ 140 km). V1 peak density is observed at ∼ 120-130 ~km. The sporadic V0 layer observation is also a major highlight of this work. We also made comparisons of our results obtained with retrievals from data received at the two ground stations (IDSN, Byalalu and UDSC, Japan) with results from Venus Express for similar SZA conditions for validation.