title: In-Body to On-Body Ultrawideband Propagation Model Derived From Measurements in Living Animals.
abstract: Ultrawideband (UWB) radio technology for wireless implants has gained significant attention. UWB enables the fabrication of faster and smaller transceivers with ultralow power consumption, which may be integrated into more sophisticated implantable biomedical sensors and actuators. Nevertheless, the large path loss suffered by UWB signals propagating through inhomogeneous layers of biological tissues is a major hindering factor. For the optimal design of implantable transceivers, the accurate characterization of the UWB radio propagation in living biological tissues is indispensable. Channel measurements in phantoms and numerical simulations with digital anatomical models provide good initial insight into the expected path loss in complex propagation media like the human body, but they often fail to capture the effects of blood circulation, respiration, and temperature gradients of a living subject. Therefore, we performed UWB channel measurements within 1-6 GHz on two living porcine subjects because of the anatomical resemblance with an average human torso. We present for the first time, a path loss model derived from these in vivo measurements, which includes the frequency-dependent attenuation. The use of multiple on-body receiving antennas to combat the high propagation losses in implant radio channels was also investigated.
authors: Pål Anders
authors: PA
authors: Floor
authors: Raúl
authors: R
authors: Chávez-Santiago
authors: Sverre
authors: S
authors: Brovoll
authors: Øyvind
authors: Ø
authors: Aardal
authors: Jacob
authors: J
authors: Bergsland
authors: Ole-Johannes H N
authors: OJ
authors: Grymyr
authors: Per Steinar
authors: PS
authors: Halvorsen
authors: Rafael
authors: R
authors: Palomar
authors: Dirk
authors: D
authors: Plettemeier
authors: Svein-Erik
authors: SE
authors: Hamran
authors: Tor A
authors: TA
authors: Ramstad
authors: Ilangko
authors: I
authors: Balasingham
mesh_terms: D000818:Animals; D003198:Computer Simulation; D005260:Female; D019736:Prostheses and Implants; D011474:Prosthesis Design; D011846:Radio Waves; D012815:Signal Processing, Computer-Assisted; D013552:Swine; D013686:Telemetry / Q000295:instrumentation*