The most important aspect is ionospheric gradients, which can reduce users of the global navigation satellite system's positional accuracy, especially in low-latitude areas. This paper's primary goal is to estimate the fluctuations in the ionospheric gradient measured by the NAVIC receiver near Guntur, India (16.23 N, 80.44 E). Total electron content (TEC) measurements of S-band (2492.028 MHz) transmissions are used to calculate ionospheric time delays and carrier phase. This study is the first to examine ionospheric gradients over a low-latitude region using NAVIC's S-band signals. The RLS algorithm, short for recursive least squares, is implemented as a single frequency ionospheric model for determining the absolute TEC and the ionospheric gradients along the longitudinal (E-W) and latitudinal (N-S) axes.Also addressed is the annual statistical analysis of the periodic nature of the spatial ionospheric gradients observed in NAVIC S-band signals from June 2016 to May 2017. The RLS model clearly has the ability to predict ionospheric gradients for a single NAVIC station.The results of this effort will help us understand the climatology of ionospheric abnormalities across low-latitude regions.