The goal of the proposed research is to fully develop and characterize the ultrasound/tissue communication channel and to demonstrate wireless control of an implanted medical device (IMD) and live video streaming through tissue via the ultrasound communication channel. The development of new enabling technologies to provide the means for personalizing medical care is highly significant. Among these enabling technologies, wearable medical devices or IMDs in humans will play a pivotal role in providing continuous diagnostic information without the need for the patient to visit the clinic. In the near future, diagnostic information from such devices will interact with external wireless networks to send diagnostic information to physicians for clinical evaluation. While sending information from wearable medical devices to external wireless devices for transmission to the clinic is straightforward, transmission of diagnostic information from IMDs to an external device is still a developing technology. To realize wireless communication with IMDs, communication channels from an external device to the IMD must be high speed, safe, low power, reliable and the transmission and receiving elements on the IMD need to be small in size. To meet these needs, communication channels are being explored to transmit diagnostic information from IMDs to external receivers and vice versa. Up to now, the acoustic or ultrasonic communication channel has been overlooked primarily because it was thought that ultrasonic communication rates are too slow for transmitting information such as medical diagnostics. However, recently in our laboratory, we demonstrated the capability to transmit acoustic information at clinical ultrasonic frequencies with data rates of 120 Mbps, a new world record. Further, we demonstrated 30 Mbps data rates through thick layers of pork loin and beef liver. The development of an ultrasonic communication channel in the body will have a significant impact in medical care. However, this technology must be demonstrated in tissues and living systems and its capabilities well documented and developed. The development and demonstration of the ultrasonic communication channel in tissues will provide a safe, reliable and high speed alternative to conventional electromagnetic communications. To develop and demonstrate the ultrasonic communication channel for biomedical applications we have proposed two specific aims. Our first specific aim is to develop and characterize the acoustic communication channel and integration of ultrasonic sources with small devices to transfer data through tissue. For this aim we will quantify the communication efficiencies in tissues versus attenuation, penetration depth and data rate using transducers having different bandwidths, directionalities and output properties. In the second aim we will demonstrate the ability to communicate diagnostic information and video streaming through tissues at high data rates (i.e., >10 Mbps) using ultrasound. The demonstrations will include controlling of a device implanted and live video streaming through large tissue samples and in vivo in rabbits.
The proposed project will demonstrate that ultrasound can be used as a communication channel in the body for interfacing wirelessly with implanted medical devices. To further develop the ultrasound/tissue communications channel we will first fully characterize ultrasonic communications in the body over a variety of bandwidths, penetration depths, attenuation values and data rate values. Demonstration of the technology will include high speed data rate communications, live video streaming through the body and control of an implanted device.
