@INPROCEEDINGS {34383, author={S. Daskalakis and R. Correia and G. Goussetis and MT Tentzeris and N.B.C. Carvalho and A. G. Georgiadis}, doi={}, booktitle={IEEE International Microwave Symposium IMS}, title={Spectrally Efficient 4-PAM Ambient FM Backscattering for Wireless Sensing and RFID Applications}, year={2018}, month={June}, volume={}, pages={-} }