@ARTICLE {21580,
author={R.  Correia and A. Boaventura and N.B.C. Carvalho},
doi={10.1109/TMTT.2017.2661262},
journal={IEEE Transactions on Microwave Theory and Techniques},
title={Quadrature Amplitude Backscatter Modulator for Passive Wireless Sensors in IoT Applications},
year={2017},
month={February},
volume={65},
number={4},
pages={1103-1110},
ISSN={0018-9480}
}