Abstract

Backscatter communication has emerged as a key enabling technology for ultra-low-power and batteryless wireless platforms, especially in the context of the Internet of Things (IoT) and pervasive sensing systems. Traditional designs often treat the antenna and RF circuitry independently, leading to suboptimal performance due to impedance mismatches, low energy harvesting efficiency, and poor communication reliability. Flexible materials and novel antenna structures have gained attention for wearable, implantable, and conformal applications but face challenges in maintaining performance consistency under mechanical deformation. This paper proposes a co-design methodology for flexible RF/antenna systems to optimize energy harvesting and communication efficiency in wirelessly powered backscatter communication platforms. The method integrates the antenna and RF front-end design to ensure impedance matching, maximize power transfer, and enable flexible operation. A meandered dipole antenna integrated with a Schottky-diode-based rectifier is designed using flexible polyimide substrate. The design ensures mechanical flexibility while achieving high RF-DC conversion efficiency. Simulations using CST Microwave Studio and co-simulation with Keysight ADS validate the antenna-rectifier co-design. Experimental results show up to 52% RF-DC conversion efficiency at 915 MHz under +5 dBm input power. Backscatter communication using On-Off Keying (OOK) achieves a range of 6 meters with minimal bit error rate under ambient powering conditions. The co-design improves energy harvesting by 19.4% and communication range by 27% compared to non-co-designed setups.