Implementation of the Earth-based planetary radio occultation inversion technique

Zhang, Sujun; Ping, Jinsong; Han, Tingting; Xiaofei, Mao; Zhang, Hong

doi:10.1007/s11433-011-4247-7

Cited by 5 publications

(4 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Although the Mars RO data have been widely used in the literature, its retrieval algorithm has not been studied comprehensively, especially parameter optimization (Cahoy et al, ; Fjeldbo et al, ; Withers et al, ; Zhang S J et al, , ; Zou H et al, ). In this paper, we first outline how the frequency residuals and differential Doppler data from MaRS are utilized to determine the vertical electron density profile (EDP) of the ionosphere.…”

Section: Introductionmentioning

confidence: 99%

Optimization of the Mars ionospheric radio occultation retrieval

Wang

Yue

Wei

et al. 2018

Earth and Planetary Physics

View full text Add to dashboard Cite

Electron density is a key parameter to characterize Martian ionospheric structure and dynamics. Based on the ephemeris and auxiliary information derived from the Spacecraft, Planet, Instruments, C‐matrix, and Events (SPICE) toolkit, we calculated the bending angle of signal path from the frequency residuals measured by the Mars Express Radio Science Experiment (MaRS) of the Mars Express (MEX) mission under the assumption of a spherically symmetric ionosphere. We stratified the ionosphere into layers and assumed a linear change of bending angle between layers, to derive profiles in radial distance of refractivity with the optimized parameters of upper integral limit of 4890 km and baseline correction boundary of 3690 km. Meanwhile, we also compared the retrieved electron density profiles between the frequency residuals of the single‐frequency and differential Doppler of the dual‐frequency. In total, ~640 electron density profiles of Martian ionosphere between April 2004 and April 2015 were retrieved successfully. There are 24 profiles identified manually that exhibit an additional sporadic layer occurrence below the normal two‐layers. We also found that the peak altitude of this layer increases with the main peak altitude.

show abstract

Section: Introductionmentioning

confidence: 99%

Optimization of the Mars ionospheric radio occultation retrieval

Wang

Yue

Wei

et al. 2018

Earth and Planetary Physics

View full text Add to dashboard Cite

show abstract

“…After subtracting the classical geometrical Doppler shift caused by the relative movement between the spacecraft and the ground station, as well as the effect of transmission through Earth's atmosphere and ionosphere, signal variations caused by Venus' atmosphere and ionosphere were left in the Doppler residuals. Then the Doppler residuals can be used to retrieve the molecular number density, pressure and temperature profiles of the atmosphere and electron density profiles of the ionosphere by the planetary occultation observation processing software, which is described in Zhang et al (2011).…”

Section: Radio Sounding Of Venus' Ionospherementioning

confidence: 99%

Ionospheric inversion of the Venus Express radio occultation data observed by Shanghai 25 m and New Norcia 35 m antennas

Zhang

Jian

et al. 2015

Res. Astron. Astrophys.

View full text Add to dashboard Cite

The electron density profile (from 110 km to 400 km) retrieved from the X-band egress observation at Shanghai station, shows a single peak near 147 km with a peak density of about 2 × 10 4 cm −3 at a solar zenith angle of 94• . As a comparison, the VEX radio science (VeRa) observations at New Norcia station were also examined, including S-, X-band and dual-frequency data in the ingress mode. The results show that the electron density profiles retrieved from the S-band data are more analogous to the dual-frequency data in the profile shape, compared with the X-band data. Generally, the S-band results slightly underestimate the magnitude of the peak density, while the X-band results overestimate that. The discrepancy in the X-band profile is probably due to the relatively larger unmodeled orbital errors. It is also expected that the ionopause height is sensitive to the solar wind dynamical pressure in high and intermediate solar activities, usually in the range of 200 km -1000 km on the dayside and much higher on the nightside. Structural variations ("bulges" and fluctuations) can be found in the electron density profiles in intermediate solar activity, which may be caused by the interaction of the solar wind with the ionosphere. Considerable ionizations can be observed in the Venus' nightside ionosphere, which are unexpected for the Martian nightside ionosphere in most cases.

show abstract

“…With the rise of the Global Navigation Satellite System (GNSS), the radio occultation technique has been widely employed for examining the Earth's atmosphere [18,19]. Researchers have also advanced scientific works, including on the processing of data from Mars radio occultation observations and the analysis of characteristics within the Mars atmosphere and ionosphere [20][21][22][23][24].…”

Section: Introductionmentioning

confidence: 99%

Preliminary Estimations of Mars Atmospheric and Ionospheric Profiles from Tianwen-1 Radio Occultation One-Way, Two-Way, and Three-Way Observations

Liu,

Chen,

Jian

et al. 2023

Remote Sensing

Self Cite

View full text Add to dashboard Cite

The radio occultation method, one of the methods used to provide planetary atmospheric profiles with high vertical resolution, was applied to China’s first Mars mission, Tianwen-1. We carried out observations based on the Chinese Deep Space Network, and one-way, two-way, and three-way modes were used for Doppler observations from the Tianwen-1 spacecraft. We successfully obtained effective observations from Tianwen-1 on 22 and 25 March 2022. An inversion system developed for Tianwen-1 radio occultation observations enabled the derivation of neutral atmospheric density, pressure, temperature, and electron density profiles of Mars. Utilizing one-way tracking data, Martian ionospheric electron density profiles were retrieved at latitudes between 68.7 and 70.7 degrees (N). However, the presence of strong random walk noise in one-way tracking data led to poor inversion results. Meanwhile, Martian ionospheric electron density and neutral atmosphere profiles were extracted from two-way and three-way tracking data at latitudes between 55.1 and 57.0 degrees (S) on 22 March and at latitudes between 62.8 and 63.4 degrees (S) on 25 March. Importantly, our inversion results from Tianwen-1 maintained consistency with results from the Mars Express and the Chapman theory (mainly in the M2 layer). Through two days’ observation experiments, we established and verified the occultation solution system and prepared for the follow-up occultation plans.

show abstract

Implementation of the Earth-based planetary radio occultation inversion technique

Cited by 5 publications

References 28 publications

Optimization of the Mars ionospheric radio occultation retrieval

Optimization of the Mars ionospheric radio occultation retrieval

Ionospheric inversion of the Venus Express radio occultation data observed by Shanghai 25 m and New Norcia 35 m antennas

Preliminary Estimations of Mars Atmospheric and Ionospheric Profiles from Tianwen-1 Radio Occultation One-Way, Two-Way, and Three-Way Observations

Contact Info

Product

Resources

About