Impact of Ambiguity Statistics on Information Retrieval for Conventional and Novel SAR Modes

Synthetic aperture radar (SAR) is an all-weather imaging tool with several applications in the field of Earth observation. In recent years, novel SAR modes have been developed, where either the pulse repetition interval (PRI) or the transmitted waveform or phase is continuously varied, leading to smeared ambiguities. Ambiguities with the same total energy but different statistical distributions are likely to have different influences on the retrieval of information from SAR images. This paper analyzes the ambiguity statistics and addresses their impact on selected applications for conventional and novel SAR modes through simple models and simulations based on TerraSAR-X and TanDEM-X data. The reported results show that an understanding of the ambiguity statistics and of the impact of their smearing on product performance is fundamental to select the SAR operation mode within the design of future SAR systems.