From the Georgia Tech Research Corporation, a nice summary of one of our lab’s patents, co-authored by Yenpao “Albert Lu” and Gregory Koo:
Inventors at Georgia Tech have developed techniques that can extend the range and the potential data rate of low-power communication. These techniques use multiple antennas at the transmitter, receiver, and RF tag and will soon allow the exchange of low data rates over long distances. The techniques have the capability to allow RF tags to return high powered signals with higher data rates back to a reader unit. This allows for the sweeping of an RF waveform through space so that passive radio devices may more effectively harvest energy and boost the collection of microwave power by an energy-harvesting RF tag using multiple antennas. Collectively, these techniques work together to enhance the range and reliability of RF tags.
Download the summary at 5147.