COMPACT RECTENNA DESIGN FOR LOSSY PAPER SUBSTRATE AT 2.45 GHZ

This work presents a compact rectenna based on printed on paper electronics. The rectenna is printed using mass production technique on an environmental-friendly and flexible paper substrate. Only one ink layer is used. The characterized paper substrates present minimum tangent losses of 0.08. It shows at most 40 times higher tangent loss than commercial substrates (Rogers Ultralam2000). A reduction of 50% of dielectric losses can be achieved by a good selection of the paper type; the selected paper substrate is a corrugated cardboard with 0.04 loss tangent value. The designed rectenna is based on two series-mounted SMS7630 Schottky diodes. Co-design technique has been used in order to integrate different blocks for additional loss reduction. The goal of our work is the use of a recyclable cardboard substrate with low-losses compared to classical paper substrate and high losses compared to commercial substrates. The printed on cardboard rectenna presents similar performances to a rectenna etched on commercial substrates. This device aims to convert high voltage levels (1 V) at low power levels (15 dBm) for self-sustainable devices. For our application, an electrochromic display is supplied for anti-counterfeiting purposes. When a smartphone operating on Wi-Fi mode is close, the printed rectenna exhibits 970 mV DC which is sufficient to turn on the electrochromic display.