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Showing posts from May, 2017

Ghost Talk

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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 is modulated correctly, then the peaks of the carri