The Cassini RADAR altimeter has provided broadscale surface topography data for Saturn's largest moon Titan. Herein, we adapt the Delay-Doppler algorithm to take into account Cassini geometries and antenna mispointing usually occurring during hyperbolic Titan flybys. The proposed algorithm allows up to tenfold improvement in the along-track resolution. Preliminary results are provided that show how the improved topography presented herein can advance our understanding of Titan's surface characteristics.

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We readapt ultrawideband (UWB) processing to enhance the range resolution of the Mars Advanced Radar for Subsurface and Ionosphere Sounding (MARSIS) up to a factor of 6 (25 m). The technique provides for the estimation of radar signature over a wider spectrum via the application of wellknown super-resolution (SR) techniques to adjoining subbands. The measured spectra are first interpolated and then extrapolated outside the original bands. The revised algorithm includes the estimation and removal of ionospheric effects impacting the two signals. Because the processing requires the realignment of the echoes at different frequencies, we derived the maximum tolerable retracking error to obtain reliable super-resolved range profiles. This condition is fulfilled by low-roughness areas compared to MARSIS wavelength, which proves to be suitable for the application of our processing. Examples of super-resolved experimental products over different geological scenarios show the detection of shallow dielectric interfaces not visible from original MARSIS products. Our results are validated by comparison with the Shallow Radar (SHARAD) data acquired at the crossovers, demonstrating the potential of the method to provide enhanced imaging capabilities.

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Orbital radar sounders are a useful tool to investigate planetary bodies. The sounding signal lies in the high frequency or very high frequency band, allowing a good ground penetration but limiting the system's resolution. Moreover, electromagnetic interference (EMI) may affect the system, increasing the noise in the radar products. In this Letter, a method to enhance the resolution and to suppress the EMI is presented. The method's performance and the parameters setting are investigated. Finally, some results for the Mars Advanced Radar for Subsurface and Ionosphere Sounding and for the Shallow Radar sounders are presented.