UHF solar powered active oscillator antenna on low cost flexible substrate for wireless identification applications

The design of a 920 MHz active oscillator antenna using low cost flexible substrate materials is presented. Flexible amorphous silicon a-Si solar cells are properly integrated in the available area of the circuit substrate preserving the conformal nature of the circuit and providing operational autonomy by harvesting solar power without affecting the radiation properties of the active antenna. Coplanar waveguide fed monopole and slot antennas are designed using EM simulation and harmonic balance simulation is subsequently used to design the oscillator circuit, including the equivalent circuit of the solar module. Two benchmarking prototypes were fabricated, one by method of laser prototyping on PET, and the other by inkjet-printing on photopaper, demonstrating that it is feasible to come up with a cost effective conformal circuit implementation of a beacon signal generator which can find application in wireless identification and monitoring applications.