ESTIMATION PERFORMANCE OF SOIL MOISTURE WITH GPS-IR METHOD

Authors : Cemali ALTUNTAŞ, Nursu TUNALIOĞLU

Pages : 2217-2230

View : 49 | Download : 6

Publication Date : 2021-10-05

Article Type : Research Paper

Abstract :This study aims to retrieve soil moisture from Global Positioning System insert ignore into journalissuearticles values(GPS); Signal-to-Noise Ratio insert ignore into journalissuearticles values(SNR); data with varying analysis to compute the best-fitting analyzing methodology. Phase, amplitude, and reflector height, which are SNR-derived interferogram metrics are examined and results are proofed with respect to correlation coefficients compared with in-situ measurements. Here, Soil Moisture Content insert ignore into journalissuearticles values(SMC); is estimated from SNR data with four data analyzing strategies using Lomb Scargle Periodogram to retrieve dominant frequency as; insert ignore into journalissuearticles values(1); considering it is four times greater than background noise assuming the reflector height is inconstant in each day, insert ignore into journalissuearticles values(2); considering it is three times greater than background noise assuming the reflector height is inconstant in each day, insert ignore into journalissuearticles values(3); assuming the reflector height is constant and median values are used for overall estimations in each day, insert ignore into journalissuearticles values(4); assuming the reflector height is constant and median values are used in each day. To do that, the GPS Interferometric Reflectometry insert ignore into journalissuearticles values(GPS-IR); method was implemented to the data of OSOR station, installed in Chile insert ignore into journalissuearticles values(within the scope of the CAP Andes GPS Network Project carried out by UNAVCO);, during 213 days from 01 January 2015 to 31 July 2015. Validation of the estimates is done by the recorded soil moistures from the Oromo Calibration Site in the LAB-net network. Results show that SMC estimated from SNR-derived metrics shows well agreement with in-situ measurements i.e. as the highest correlation of 95%; whilst the second strategy was followed.
Keywords : Global Positioning System Interferometric Reflectometry GPS IR, Signal to Noise Ratio SNR, Soil Moisture Content

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