Abstract
This paper discussed a frequency-dependent distributed beamforming technique to improve the reliability in implant multiple-input multiple-output (MIMO)-ultra wideband (UWB) communications. To realize distributed beamforming for implant MIMO-UWB systems, we propose an optimization method to theoretically determine the weight coefficients optimized for the implant UWB communication. To evaluate the performance improvement, the propagation characteristics of the implant channel in the low band UWB (3.4–4.8 GHz) were analyzed by the finite difference time domain (FDTD) method with a numerical human model. Subsequently, this study conducted computer simulations based on the derived propagation channel model. The evaluation results demonstrate that the proposed beamforming effectively improved the \(E_b/N_0\) performance by 5 dB in a capsule endoscopy scenario, compared to the conventional method, which can improve implantable medical devices in the future.
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Data availability
The datasets generated and/or analysed during the current study are not publicly available due to Patent restrictions, but are available from the corresponding author on reasonable request.
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Acknowledgements
The authors would like to thank Mr. Takuma Suzaki for his contribution to the communication performance evaluation.
Funding
This research was supported in part by JST Moonshot R&D Grant Number JPMJMS2214-06, the JSPS KAKENHI Grant Number 24K00885 and MIC/FORWARD Grant Number JPMI250830001.
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T.K., J.H., M.F. and D.A. conceived the experiments, J.H. M.F. and T.K. conducted the simulations, and analysed the communication performance results. D.A. provided the project funding acquisition. All authors contributed to the writing and review of the manuscript.
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Kobayashi, T., Hyry, J., Fujimoto, M. et al. Weight optimization of MIMO-UWB distributed beamforming for implant communications. Sci Rep (2026). https://doi.org/10.1038/s41598-026-36694-w
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DOI: https://doi.org/10.1038/s41598-026-36694-w
