Mitigation of Radio Frequency Interference in Synthetic Aperture Radar Data: Current Status and Future Trends

Abstract

Radio frequency interference (RFI) is a major issue in accurate remote sensing by a synthetic aperture radar (SAR) system, which poses a great hindrance to raw data collection, image formation, and subsequent interpretation process. This paper provides a comprehensive study of the RFI mitigation techniques applicable for an SAR system. From the view of spectrum allocation, possible terrestrial and spaceborne RFI sources to SAR system and their geometry are analyzed. Typical signal models for various RFI types are provided, together with many illustrative examples from real measured data. Then, advanced signal processing techniques for removing RFI are reviewed. Advantages and drawbacks of each approach are discussed in terms of their applicability. Discussion on the future trends are provided from the perspective of cognitive, integrated, and adaptive. This review serves as a reference for future work on the implementation of the most suitable RFI mitigation scheme for an air-borne or space-borne SAR system.

RFI Artefacts Detection in Sentinel-1 Level-1 SLC Data Based On Image Processing Techniques

“…In the SAR images these incoherent electromagnetic interference signals usually appear as various kind of bright linear features [30,31] like bright stripes with curvature or dense raindrops [2,4]. RFI introduces artefacts in image by slight haziness [2,31] that acutely degrade its quality [4,30]. Such affected images may lead to wrong interpretation process and results [2].…”

“…RFI introduces artefacts in image by slight haziness [2,31] that acutely degrade its quality [4,30]. Such affected images may lead to wrong interpretation process and results [2].…”

“…The reason for RFI contamination for SAR is that many different radiation sources operate with the same frequency band as the SAR system [2,30]. In general they can be grouped into terrestrial and space-borne sources [2].…”

“…The reason for RFI contamination for SAR is that many different radiation sources operate with the same frequency band as the SAR system [2,30]. In general they can be grouped into terrestrial and space-borne sources [2]. Most of these incoherent electromagnetic interference signals are emitted by terrestrial commercial or industrial radio devices [2], e.g., communication systems, television networks, air-traffic surveillance radars, meteorological radars, radiolocation radars, amateur radios and other, mainly military-based, radiation sources [2,4,30,31].…”

“…SAR is an active microwave remote sensing tool [2] with wide spatial coverage, fine resolution, all-weather and day-and-night image acquisition capability [3,4]. These features allow the ability to use SAR images for a multitude of scientific research, commercial and defense applications ranging from geoscience to Earth system monitoring [2,4,5].…”