Abstract
Implantable biomedical sensors with the ability to
transmit wirelessly real-time physiological data to an external
unit can enable better management of chronic diseases. The
IEEE Standard 802.15.6-2012 specifies the implementation of
implant communications within 402-405 MHz, which
unfortunately allows low data transmission rates only. Ultra
wideband (UWB) interfaces within 3.1-10.6 GHz offer a number
of advantages at the expense of higher path losses. Efforts to
characterize the implant UWB channel have been undertaken via
computer simulations, but these may not capture completely the
effects on the implant radio channel of multiple physiological
functions. To overcome these limitations we provide insight into
the frequency-domain behavior of the UWB implant channel
within 3.1-8.5 GHz based on propagation measurements in a
liquid phantom and a living swine. A thorough comparison of the
relative received power in phantom-based and in vivo
measurements for the in-body to on-body (IB2OB) and in-body
to off-body (IB2OFF) channel scenarios are presented.
