Analysis of the inverted-F antennas integrated on the displacement detector for wireless sensor network applications

A printed inverted-F antenna integrated on the displacement detector for wireless sensor network applications is designed and studied. The antenna, the ground plane, and other required components are integrated onto a two-layer FR-4 PCB. The antennas with two rectangular plates, with circuit layout, and with mounted ICs are analyzed, respectively. Adding the circuit layout on the PCB shifts the working frequency of the antenna to the lower one, decreases the antenna gain and efficiency, and ripples the radiation patterns. The mounted ICs increase the antenna frequency, bring the return loss to the margin of -10 dB, but affect the radiation pattern insignificantly. Designing the optimal circuit layout from the point of view of antenna parameters is an important step to improve the performance of the proposed displacement detector fabricated on a two-layer FR-4 PCB.