1 research outputs found
Skin-MIMO: Vibration-based MIMO Communication over Human Skin
We explore the feasibility of Multiple-Input-Multiple-Output (MIMO)
communication through vibrations over human skin. Using off-the-shelf motors
and piezo transducers as vibration transmitters and receivers, respectively, we
build a 2x2 MIMO testbed to collect and analyze vibration signals from real
subjects. Our analysis reveals that there exist multiple independent vibration
channels between a pair of transmitter and receiver, confirming the feasibility
of MIMO. Unfortunately, the slow ramping of mechanical motors and rapidly
changing skin channels make it impractical for conventional channel sounding
based channel state information (CSI) acquisition, which is critical for
achieving MIMO capacity gains. To solve this problem, we propose Skin-MIMO, a
deep learning based CSI acquisition technique to accurately predict CSI
entirely based on inertial sensor (accelerometer and gyroscope) measurements at
the transmitter, thus obviating the need for channel sounding. Based on
experimental vibration data, we show that Skin-MIMO can improve MIMO capacity
by a factor of 2.3 compared to Single-Input-Single-Output (SISO) or open-loop
MIMO, which do not have access to CSI. A surprising finding is that gyroscope,
which measures the angular velocity, is found to be superior in predicting skin
vibrations than accelerometer, which measures linear acceleration and used
widely in previous research for vibration communications over solid objects