Sea-Spike Detection in High Grazing Angle X-Band Sea-Clutter

Knowledge of sea-clutter phenomenology allows accurate models to be developed for assessing target detection performance. The majority of work in this area has been at low grazing angles from clifftops or wave tanks and does not consider scattering in the high grazing angle region beyond 10 °. To improve our understanding at high grazing angles of 15 ° -45 °, the Defence Science and Technology Organisation´s Ingara airborne X-band fully polarimetric radar has been used to collect 12 days´ worth of sea-clutter data. This paper focuses on understanding the characteristics of sea-spikes as they are often the cause of false detections in a radar processor. Using the Ingara data, a threshold is used to isolate these scatterers in the range/time domain with results verified against the KK probability distribution function. Detections due to discrete and persistent scattering are then isolated to provide more information regarding the underlying cause of sea-spikes and answer the question of whether Walker´s three-component mean Doppler spectrum model is suitable at high grazing angles.