One of our ECE seniors, Martin Sebastian Ferndandez, has compiled a great lecture series on YouTube for learning/reviewing differential equations. The series follows topics in MATH 2552 Differential Equations, one of the required engineering courses offered by the GT Math school. A great resource for students and researchers alike.
Archives for November 2018
Anil Rohatgi’s 2006 Spread Spectrum Tag
2006: Anil Rohatgi builds a 915 MHz spread spectrum multi-tag system that demonstrates polarization and space diversity in a real backscatter communications link.
This 2006 experiment was a landmark for many reasons. It was the group’s first foray into coding theory for backscatter systems. It also garnered an invite to the 2008 IEEE RFID conference in Las Vegas … a relationship that has turned surprisingly long-term.
Tunnel Diodes for Backscattering Communications
Tunnel Diodes for Backscattering Communications
Francesco Amato, Gregory D. Durgin
2018 2nd URSI Atlantic Radio Science Meeting (AT-RASC)
The authors give an overview about the research progresses done in the latest years to enhance ranges of microwave backscattering communications with RFIDs exploiting the tunneling effect of tunnel diodes. The first prototype of a Tunneling RFID Tag built using a tunnel diode outperformed semi-passive tags by at least a factor of 5 in range. Tests on the 5.8 GHz backscattering link reached 1.5 km of ranges and demonstrated that a DC power of only 20.4 μW and 2.9[pJ/bit] are required to operate the Tunneling Tag.
The First 915 MHz RF Downconverter
915 MHz RF Downconverter: Albert Lu builds the group’s first direct downconversion receiver box for backscatter, allowing ground-breaking experiments and a template for operating at higher frequencies.
This direct downconversion hardware at 915 MHz produced a filtered baseband IQ receiver output that enabled the first round of serious backscatter modulation experiments by the group. Deigned by Albert Lu, it was a prelude to the microwave hardware that would constitute the 5.8 GHz backscatter system.