Science Daily June 25, 2021
Backscatter radio is typically limited to data rates of hundreds of megabits per second because of the low frequency bands used and the modulation techniques involved. An international team of researchers (USA – industry, Georgia Institute of Technology, UK) designed and demonstrated a millimetre-wave modulator and antenna array for backscatter communications at gigabit data rates. It consists of a microstrip patch antenna array and a single pseudomorphic high-electron-mobility transistor that supports a range of modulation formats including binary phase shift keying, quadrature phase shift keying and quadrature amplitude modulation. The circuit is additively manufactured with inkjet printing using silver nanoparticle inks on a flexible liquid-crystal polymer substrate. A millimetre-wave transceiver is designed to capture and down convert the backscattered signals and route them for digital signal processing. They demonstrated a bit rate of two gigabits per second of backscatter transmission at millimetre-wave frequencies of 24–28 GHz, and with a front-end energy consumption of 0.17 pJ per bit.v…read more. Open Access TECHNICAL ARTICLE
Oscilloscope measurements from demodulated gigabit backscatter constellations and spectra. Credit: Nature Electronics volume 4, pages 439–446 (2021)Â