Evaluation of Harvest Status in Sugarcane Fields, Khon Kaen Province, Thailand using Sentinel-1 SAR Data

Abstract

In this study, the Synthetic Aperture Radar (SAR) satellite image technology was employed to monitor the status of sugarcane fields and determine whether they had been harvested or not. The study was conducted during the closing season of sugar cane factories in Khon Kaen, utilizing L1 Ground Range Detection (GED) Polarization VV satellite image data from the Sentinel-1 satellite between 25 April 2021, and 14 December 2023, covering the Khon Kaen area (Path 164 Frame 538/ Path 164 Frame 533). A total of 14,971 sugarcane plots were surveyed in April 2021 to establish an appropriate backscatter trend to assess the status of the sugarcane fields. It was demonstrated that a backscatter range of -7.000 to -12.999 dB tended to represent harvested sugarcane fields. The accuracy of the study was verified by comparing the backscatter data with surveyed plots from the field on 18 January 2023, which indicated an accuracy of 83.017 percent, similar to the current system. The optical satellite results revealed an accuracy of 83.135 percent, suggesting that the SAR system could also be utilized to monitor the harvest.