(Georgia Institute of Technology, 2010-11)
Griffin, Joshua D.; Durgin, Gregory D.
Multipath fading can be heavy for ultra-high frequency
(UHF) and microwave backscatter radio systems used in
applications such as radio frequency identification (RFID). This
paper presents measurements of fading on the modulated signal
backscattered from a transponder for backscatter radio systems
that use multiple antennas at the interrogator and transponder.
Measurements were performed at 5.8 GHz and estimates of the
backscatter channel envelope distributions and fade margins
were calculated. Results show that multipath fading can be reduced
using multiple transponder antennas, bistatic interrogators
with widely separated transmitter and receiver antennas, and
conventional diversity combining at the interrogator receiver.
The measured envelope distribution estimates are compared to
previously derived distributions and show good agreement.