Slotted Microstrip Patch Antenna for Improved Sensing of Moisture Content in Leaf

The study of the molecular resistance against drought stress through the measurement of moisture content in leaf tissues leads to better plant management and breeding techniques. Implementation of a slotted patch antenna is presented for a non-destructive assessment of the moisture content of leaves at the resonant frequency of 2.80 GHz. The proposed antenna sensor is designed on an inexpensive F4B substrate having a thickness of 0.8 mm, dielelectric constant εr of 2.65, and a reduced dimension of 34.8 mm x 41.3 mm. Slots are employed above the feed line to miniaturize the size of the antenna. By positioning the wet leaf on a patch antenna sensor, the Vector Network Analyzer (VNA) is utlized to analyze the frequency variation in proportion to the moisture content. Subsequently, parametric analysis is carried out to demonstrate the actual behavior of the proposed technique with regard to the frequency of the designed antenna sensor. The dry and wet weight of the leaf are analyzed to determine the moisture content. The methodology is validated by the experimental results, which agree well with the simulation results.