Impact of the Sternotomy Wires and Aortic Valve Implant on the On-Body UWB Radio Channels

IEEE Trans. Antennas Propagat.

Kumpuniemi

et al. 2019

Self Cite

This paper presents a comprehensive study on the impact of sternotomy wires and a medical implant on the ultra-wideband (UWB) channel characteristics by studying intra-body propagation in the vicinity of on-body antennas. The main contribution on this work is to verify propagation path calculations with measurement data taken from a volunteer that has sternotomy wires and an aortic valve implant and from a reference volunteer without any implants. Furthermore, the impact of sternotomy wires and the aortic valve implant is confirmed by finite integration technique simulations using a tissue layer model. It is shown, that additional signal peaks and variations of the channel impulse responses are observed for the medical implant case, since both sternotomy wires and aortic valve implant contain highly conductive materials which impacts on the channel characteristics. In the time domain simulation results, the difference between the channel strength of the implanted and non-implanted cases varies between 5-17 dB within the time range corresponding to the relevant propagation paths. This phenomenon should be taken into account when designing on-body monitoring devices and when choosing sensor node locations to avoid interference due to the additional multipath propagated signal components. On the other hand, knowledge of the impact of the aortic valve implant may be utilized in the design of devices that can monitor the functionality of a valve implant during the heartbeat. Index Terms-Aortic valve implant, intra-body propagation, channel characteristics, sternotomy wires, wireless body area networks. Manuscript received March 8, 2018. This work has been funded by the project Wireless Body Area Networks Communications in the Congested Environments project at University of Oulu and in part Academy of Finland 6Genesis Flagship project (grant 318927).

Section: Introductionsupporting

confidence: 61%

Section: A Asymmetric Case With Antenna Distance 65 CMmentioning

confidence: 99%

Section: A Asymmetric Case With Antenna Distance 65 CMmentioning

confidence: 99%

Section: A Asymmetric Case With Antenna Distance 65 CMmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Measurement Data-Based Study on the Intrabody Propagation in the Presence of the Sternotomy Wires and Aortic Valve Implant

IEEE Trans. Antennas Propagat.

Kumpuniemi

et al. 2019

Self Cite

A Finite Integration Technique-Based Simulation Study on the Impact of the Sternotomy Wires on the UWB Channel Characteristics

13th EAI International Conference on Body Area Networks

Kumpuniemi

et al. 2020

Self Cite

This paper presents for the first time a simulation study on the impact of the sternotomy wires on the ultra wideband (UWB) channel characteristics. The simulations are based on the finite integration technique (FIT). The simulation results are verified with the propagation path calculations as well as with the measurement data. It is found that there is a clear correspondence between the simulated and measurement results as well as with the propagation path calculations which allows smooth transceiver algorithm investigation.

Comprehensive Study on the Impact of Sternotomy Wires on UWB WBAN Channel Characteristics on the Human Chest Area

et al. 2019

IEEE Access

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This paper presents a comprehensive study on the impact of the sternotomy wires on the characteristics of ultra wideband (UWB) radio propagation channel in the human chest area. The study is conducted using two simulation models: a planar layer model and a three-dimensional elliptical layer model. The study includes antennas designed for on-body and in-body communications. Furthermore, the measured data and propagation path calculations are presented to verify the simulation results. The main purpose is to show how the steel wires affect the on-body channel characteristics and in-body propagation within the tissues when the monitoring antennas are located in close vicinity of the human body. The study is conducted by evaluating: 1) channel characteristics in both frequency and time domains; 2) 2D power flow figures; and 3) Poynting vector values. Furthermore, the impact of the fat layer thickness on the visibility of sternotomy wires is studied. Moreover, the impact of sternotomy wires is studied for the case of the recently operated patient, for which the sternotomy wires are on the sternum bone surface, as well as for the case where the sternotomy wires are embedded into the sternum bone. It is found that sternotomy wires have a clear impact on the channel. The strength of the impact depends on the antenna types used by the monitoring devices, the thickness of the fat layer in the sternum area, and whether the sternotomy wires are on the sternum surface or whether they have already been embedded on the sternum as it happens with time. INDEX TERMS In-body propagation, medical implants, monitoring device, radio channel, sternum closure method, wireless body area networks.