TY - PAT
T1 - Causing microphones to detect inaudible sounds and defense against inaudible attacks
AU - Roy, Nirupam
AU - Choudhury, Romit Roy
AU - Hassanieh, Haitham Al
N1 - FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT This invention was made with government support 1619313 awarded by the National Science Foundation. The government has certain rights in the invention.
PY - 2020/6/2
Y1 - 2020/6/2
N2 - An audio transmitter includes a first ultrasonic speaker associated with a first channel; a second ultrasonic speaker co-located with the first ultrasonic speaker and associated with a second channel; and a waveform generator to: frequency modulate a first inaudible signal at a first ultrasonic frequency, to generate a modulated inaudible signal; drive, over the first channel, the first ultrasonic speaker with the modulated inaudible signal; and drive, over the second channel, the second ultrasonic speaker with a second inaudible signal at a second ultrasonic frequency so that a combination of the modulated inaudible signal and the second inaudible signal arrive at a microphone system. The second ultrasonic frequency is selected to frequency shift the modulated inaudible signal, upon demodulation by hardware of the microphone system, causing non-linearities of the hardware to translate the first ultrasonic frequency to below a low-pass filter cutoff frequency that is recordable by the microphone system.
AB - An audio transmitter includes a first ultrasonic speaker associated with a first channel; a second ultrasonic speaker co-located with the first ultrasonic speaker and associated with a second channel; and a waveform generator to: frequency modulate a first inaudible signal at a first ultrasonic frequency, to generate a modulated inaudible signal; drive, over the first channel, the first ultrasonic speaker with the modulated inaudible signal; and drive, over the second channel, the second ultrasonic speaker with a second inaudible signal at a second ultrasonic frequency so that a combination of the modulated inaudible signal and the second inaudible signal arrive at a microphone system. The second ultrasonic frequency is selected to frequency shift the modulated inaudible signal, upon demodulation by hardware of the microphone system, causing non-linearities of the hardware to translate the first ultrasonic frequency to below a low-pass filter cutoff frequency that is recordable by the microphone system.
M3 - Patent
M1 - 10672416
Y2 - 2018/10/17
ER -