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Effective management of emerging medical devices can lead to new insights in healthcare. Thus, a human body communication (HBC) is becoming increasingly important. In this paper, we present magnetic resonance (MR) coupling as a promising method for intra-body network (IBNet). The study reveals that MR coupling can effectively send or receive signals in biological tissue, with a maximum path loss of PL 33 dB (i.e. at 13.56 MHz), which is lower than other methods (e.g., galvanic, capacitive, or RF) for the same distance. The angular orientation of the transmitter and receiver coils at short and long distances also show a minor variation of the path loss (0.19 PL 0.62 dB), but more dependency on the distance (0.0547 dB/cm). Additionally, different postures during the MR coupling essentially do not affect path loss (PL 0.21 dB). In the multi-nodal transmission scenario, the MR coupling demonstrates that two nodes can simultaneously receive signals with -16.77 dBm loss at 60 cm and 100 cm distances, respectively. Such multi-node MR transmission can be utilized for communication, sensing, and powering wearable and implantable devices.
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Characterization of Magnetic Communication Through Human Body
Biomedical systems of implanted miniaturized sensors and actuators interconnected into an intra-body area net-work could revolutionize treatment options for chronic diseases afflicting internal organs. Considering the well-understood limitations of radio frequency (RF) propagation in the human body, we have explored magnetic resonance (MR) coupling for both communications and energy transfer through the body. In this paper, we have discussed the design and implementation of a software-defined prototype using Universal Software Radio Peripheral (USRP) boards. We have reported experimental results on the achieved packet error rates at different positions through-the-body distances and packet sizes. We have observed experimentally that the MR signal propagates through the body substantially better than in the air, and can provide a practical means for energy transfer and communications in intra-body networks. It also works better than the better understood galvanic coupling.
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- PAR ID:
- 10324472
- Date Published:
- Journal Name:
- 2022 IEEE 19th Annual Consumer Communications & Networking Conference (CCNC)
- Page Range / eLocation ID:
- 563 - 568
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/CCNC49033.2022.9700669
