Provided by: Creative Commons
In this paper, the authors propose two novel beam-forming methodologies, which employ passive RF devices to enhance received signal through a passive, scattering based beam forming. Currently available backscattering systems, e.g. the Radio Frequency IDentification (RFID), suffer from a poor communication in an environment with multiple passive devices. The intermediate antennas create severe scattering environment with nulls. In contrast, the proposed approach changes the scattering properties of a subset of the multiple antennas such that the received signal strength and quality is maximized.