Performance analysis of optical extra-WBAN links based on realistic user mobility modeling

Abstract

We address the features channel characterization and performance evaluation for wireless body-area networks (WBANs) in medical applications during a walk scenario using optical wireless transmission. More specifically, we focus on optical extra-WBAN uplink communication between a central coordinator node (CN) placed on the patient's body and an access point (AP) in a typical hospital room. To characterize the optical wireless channel, we use a Monte Carlo ray tracing-based method and take into account the effects of body shadowing and mobility based on realistic models, in contrast to the previous simplistic models considered in the literature. Using this approach, we derive the dynamic behavior of the channel DC gain for different configurations of the CNs and APs. Furthermore, based on the obtained results, we develop a statistical channel model based on kernel density estimation, which we use to investigate the impact of CN and AP placement on the communication link parameters. Also, based on the outage probability criterion, we discuss the link performance and further analyze the improvement in performance achieved through spatial diversity, i.e., by using multiple APs in the room, for different photodetector types, under different background noise conditions. The presented results show that CN placement and user's local and global mobility significantly impact the performance of extra-WBAN links, which can nevertheless be reduced using spatial diversity. Finally, the presented performance analysis shows that a single AP equipped with an avalanche photodiode photodetector allows an acceptable link performance for low-to-moderate background noise conditions, whereas multiple APs equipped with PIN photodetectors should be used in the case of moderate-to-strong background noise.

Performance Analysis of Multiple Access m-CAP for Optical-Based Intra-WBAN Links

“…The above-mentioned statistical models are derived based on raytracing simulations with Zemax Opticstudio software, which is used to obtain the channel impulse response and the channel DC gain H 0 = h(t) dt. These models are fitted to the simulated cumulative distribution function of H 0 based on the non-parametric kernel density estimation (KDE) method for a Gaussian kernel [22], [23]. Figure 3 shows the simulated and fitted cumulative distribution functions (CDFs) for each link between SNs and the CN.…”

A Secure Optical Body Area Network Based on Free Space Optics and Time-Delayed 2D-Spectral/Spatial Optical CDMA

“…It is projected that health expenditures will grow at the rate of 5.1% per year over 2021-30 [5]. Therefore, BANs may be acknowledged as the major constituent of e-health systems by allowing the sensing and timely transmittal of physiological data of patients from several medical sensors to remotly located medical staff [6].…”

A Secure Optical Body Area Network Based on Free Space Optics and Time-Delayed 2D-Spectral/Spatial Optical CDMA

“…E-health and telemedicine solutions are gaining popularity and being rapidly implemented globally, especially after the outbreak of COVID-19 pandemic, as a means to improve quality of life while reducing health budgets. Therefore, BANs are becoming acknowledged as a major constituent of e-health systems that allows sensing and timely transmission of patients' physiological data from several medical sensors to remotely located medical staff [6]. In this way, the workload and required number of clinical staff can be reduced using e-health solutions, resulting in higher efficiency on the part of medical staff and reduced healthcare expenditures.…”

“…OBAN is a relatively recent research field; therefore, abundant published work is not yet available. Works related to OBAN published over the past decade include [2,4,6,8,[10][11][12][13][14][15][16][17]. Mirza et al proposed secure OBAN architectures based on spectral amplitude coding-OCDMA (SAC-OCDMA) [2] and optical chaos [8].…”

“…Dhatchayeny et al proposed OBANs based on visible light communication (VLC) enabled through a mobile phone camera [4] and via orthogonal spreading codes [10], and discussed patient mobility models [11]. Haddad et al proposed FSO channel characterization and performance analysis with patient mobility [6], an intra-OBAN channel modelling and multiple access scheme [12], and channel modelling between sensors and a coordinator [13]. Chevalier et al proposed channel modelling for a diffused optical channel between on-body sensors [14] and a star OBAN topology based on a diffused optical channel and spreading codes [15].…”