|University of Illinois at Urbana-Champaign | Department of Electrical and Computer Engineering | Department of Bioengineering
Department of Statistics | Coordinated Science Laboratory | Beckman Institute | Food Science and Human Nutrition | Division of Nutritional Sciences | College of Engineering
|Friday, August 23rd, 2019|
Wireless implanted medical devices (IMDs) are rapidly becoming an integral part of medical diagnostic and treatment procedures. Currently, radio frequency (RF) electromagnetic waves are the most frequently used communication method for online wireless IMDs. However, there are various drawbacks of using RF electromagnetic waves in such applications such as the attenuation of RF waves in the body, increased risk of tissue damage caused by over-heating resulting from RF waves, and limitations on the data rates as a result of the regulations on the allocation of RF frequency spectrum.
In the Mbps Experimental Acoustic Through-Tissue Communications (MEAT-COMMS), we aim to use ultrasonic frequencies for high bandwidth data communication in vivo to work around the difficulties of wireless in-body RF communication. We propose a setup that will allow us to stream high definition video (>3 Mbps) as well as communicate with and actively control an IMD inside the body.
For that purpose, in the initial stage of the project, we showed that data rates up to 120 Mbps with bit error rate (BER) < 1e-2 can be reached with focused, highly directional immersion ultrasonic sources (Fig. 1 – 1 and 2) through water and 20-30 Mbps through beef liver and pork loin. Further experiments also demonstrate that we can reach 4 Mbps with BER < 1e-4 through 2” beef liver with 2-mm sonomicrometry crystals (Fig. 1 – 4) and 16 Mbps with BER 1.2e-3 using a 5x10mm semi-directional transducer (Fig. 1 – 3). Currently, we are working on a real-time video streaming framework that acquires compressed data from a webcam and transcieves data through appropriate media while processing and then displaying on the user interface (Fig. 4).
This work is supported b a grant from NIH (NIH R21EB020759).
Figure 1: Focused, highly directional 1 MHz (1), 10 MHz (2), semi-directional 5 MHz (3) and 2-mm sonomicrometry (4) ultrasonic transducers with inch rulers
Figure 2: 256-QAM constellation diagram of transmission and reception with 2-mm sonomicrometry crystal
Figure 3: Transmission through 2” beef liver with 2-mm sonomicrometry crystal
Figure 4: Video transmission interface
|Bioacoustics Research Lab.|