Impedance-matched sensor-tag antenna design using genetic algorithm optimization

Abstract

Optimal matching between tag antenna and integrated circuit is crucial for maximizing delivered power in remotely-powered sensor systems. The method maximizes conjugate matching between antenna with inductive reactive impedance and an integrated circuit with capacitive reactive impedance. Obtaining the desired conjugate impedance by the intrinsic antenna impedance excludes the need of an impedance matching network. This enables fully integrated sensor systems with further miniaturization. In this study the design of a meandered slot antenna with genetic algorithm optimization for an operation frequency of 2.45 GHz is proposed. Investigations on constraints limiting the power link efficiency between reader and tag antenna at system level outline possible design actions and give rise to the design flow of the antenna. Simulation results on the proposed architecture verify the performance of the designed miniaturized antenna.

Design and Analysis of UHF RFID Tag Antenna on the Surface of Cylinder

“…These transmission-line currents do not give a valuable contribution to the radiated power, but nevertheless produce losses. Resonances are achieved at much lower frequencies than in the case of straight dipole of the same height, at the expense of a narrow bandwidth and a low efficiency [4] [5]. The dipole antenna surrounds the cylinder object, the two long ends can be considered as the meander-line.…”

Dynamic impedance matching network for RF energy harvesting systems

“…Although Z in is not constant during the link time, several authors propose the matching to a Z in that for the longest range fulfills all the power requirements. Kazanc et al [5] use a method that optimize the conjugate matching between an antenna with inductive reactive impedance and an integrated circuit with capacitive reactive impedance. Obtaining an antenna with the desired conjugate impedance eliminates the need of an impedance matching network.…”