Project Updates

Last week, I read the Ghost Talk paper, and learned a lot conceptually about RF waves and modulation. This week, what I learned was mainly technical. In fact, lots of it was fiddling around with GNU Radio Companion and the USRP and troubleshooting the problems that arose. Like figuring out why the USRP wasn't detected as a device despite being connected. Or learning that there are certain limitations for the USRP and adapting the GRC flowcharts to match those constraints. Or, perhaps the most...enlightening experience: figuring out that the transmitter board connected to the USRP did not support the frequency of the antenna. (The frequency of the board supports up to 30MHz, while the antenna and the frequency attempted to be transmitted is over 400MHz) Still, every problem that arises is only a learning experience. Through debugging, I learned more about how the equipment works and interacts with the computer. And mistakes like the one of the wrong board is a memorable oversight ...

This week I read the Ghost Talk Paper  ( https://spqr.eecs.umich.edu/ papers/fookune-emi-oakland13. pdf ) and  learned about Amplitude Modulation, the concept behind transmitting AM  radio waves. What's interesting is that in terms of long-distance  communication, AM was preceded by Morse code; AM radio meant that  audio, with varied tones, could finally be transmitted. As the first broadcasting method, AM waves are the simplest. The way  that Amplitude Modulation works is by looking at two frequencies: the  frequency a receiver can accept (the carrier wave) and the frequency  the receiver should output to produce the wanted sound. For Ghost  Talk, the carrier frequency is determined by the victim device's  circuitry. The carrier frequency is the frequency of the attacker's  wave sent to the device. To transmit the audio data, though, the  amplitude of the wave is varied. If the carrier wave has the right  frequency, and...