Amplitude Characteristics of Littoral Sea Clutter Data at K-band and W-band

Abstract

Sea clutter data at millimeter wave frequencies are quite limited in the literature. Recent advancements in millimeter wave radar technology have created a potential for its use in maritime surveillance and autonomy. Hence, collecting data at this frequency range is of great interest to both academia and industry. This study reports on a field trial conducted at St Andrews in winter 2020 to collect littoral sea clutter data using K-band (24 GHz) and W-band (94 GHz) radar systems. Extensive data collection was done during the trial, where this work specifically concentrates on analysis of the amplitude characteristics of the sea clutter returns. Analysis of the dataset shows that the radar backscatter was heavily dominated by seaspikes. The modal normalized radar cross section (NRCS) values for Bragg, burst and whitecap scattering are measured to be -47, -30 and -17 dB respectively at 24 GHz in horizontal polarization and -48, -26 and -12 dB respectively at 94 GHz in circular polarization, measured at grazing angles of 1-3°. The backscatter from the smooth surface is found to be below the noise floor equivalent NRCS (-65 dB). Also, the power spectrum analysis of range-time intensity plots is discussed, revealing information on the sea surface dynamics.

2023 IEEE International Radar Conference (RADAR)

“…The most recently reported W-band sea clutter data were gathered by the present authors as part of the STREAM project (Sub-THz Radar sensing of the Environment for future Autonomous Marine platforms), where measurements of littoral waves in St Andrews, Scotland, were made in late 2020. That work reported σ 0 = -48 to -12 dB (depending on scattering type) in circular polarization for a grazing angle of 1-3°in an estimated sea state of 0-1 (littoral 2) [7].…”

Try living in the real world: the importance of experimental radar systems and data collection trials

“…As there exits virtually no radar data for sea clutter or objects in the sea above Ka-band, a programme of data collection trials is underway, Figure 10. Initial results have gathered data at 24 and 94 GHz from breaking waves in littoral conditions which will yield amplitude statistics [24] and Doppler information which will enable the development of classification algorithms suitable for obstacle avoidance. note include the NetRAD [25] and NeXtRAD [26-27] multistatic radar systems.…”