Wout Joseph

Ghent University | UGhent · Department of Information Technology

Occupational exposure limit values (ELVs) for body internal electric fields can be derived from thresholds for action potential generation. These thresholds can be calculated with electrostimulation models. The spatially extended nonlinear node model (SENN) is often used to determine such thresholds. Important parameters of these models are the mem...

Optogenetic inhibition of excitatory populations has been suggested as a novel technique for the treatment of refractory epilepsy. While this approach holds significant potential, achieving seizure suppression in animal models using optogenetics has proven challenging. This difficulty can be attributed to a suboptimal stimulation method that involv...

Knowledge of chicken density in different zones in the barn is an essential aspect of poultry welfare management, providing information on preferred zones, mobility, and influencing chicken growth, health, and economic returns for farmers. Although image and video processing techniques for chicken density estimation are commonly employed nowadays,...

In temporal interference (TI) stimulation, neuronal cells react to two interfering sinusoidal electric fields with a slightly different frequency (, in the range of about 1–4 kHz, in the range of about 1–100 Hz). It has been previously observed that for the same input intensity, the neurons do not react to a purely sinusoidal signal at or . This st...

A low-cost, tri-axial 50 Hz magnetic field monitoring sensor was designed, calibrated and verified. The sensor was designed using off-the-shelf components and commercially available coils. It can measure 50 Hz magnetic fields originating from high-voltage power lines from 0.08 µT to 364 µT, divided into two measurement ranges. The sensor was calibr...

In this paper, we investigate ultra-wideband (UWB) localization and tracking in cluttered environments. Instead of mitigating the multipath, we exploit the specular reflections to enhance the localizability and improve the positioning accuracy. With the assistance of the multipath, it is also possible to achieve localization purposes using fewer an...

In this paper, we investigate ultra-wideband (UWB) localization and tracking in cluttered environments. Instead of mitigating the multipath, we exploit the specular reflections to enhance the localizability and improve the positioning accuracy. With the assistance of the multipath, it is also possible to achieve localization purposes using fewer an...

In this paper, we present a novel localization scheme, location-aware ranging correction (LARC), to correct ranging estimates from ultra wideband (UWB) signals. Existing solutions to calculate ranging corrections rely solely on channel information features (e.g., signal energy, maximum amplitude, estimated range). We propose to incorporate a prelim...

In this presented study, we measured in situ the uplink duty cycles of a smartphone for 5G NR and 4G LTE for a total of six use cases covering voice, video, and data applications. The duty cycles were assessed at ten positions near a 4G and 5G base-station site in Belgium. For Twitch, VoLTE, and WhatsApp, the duty cycles ranged between 4% and 22% i...

Occupational exposure limit values (ELVs) for body internal electric fields can be derived from thresholds for action potential generation. These thresholds can be calculated with electrostimulation models. The spatially extended nonlinear node model (SENN) is often used to determine such thresholds. An important part of these models are the membra...

Indoor positioning technology has become undisputedly pervasive in modern society. It can be used for numerous applications in various environments, ranging from agriculture to smart industry. Among the different indoor positioning technologies, the development of the indoor visible light positioning (VLP) system has gained momentum recently thanks...

Background To seek appropriate veterinary attention for horses with colic, owners must recognise early signs. Direct observation of horse behaviour has several drawbacks: it is time‐consuming, hard to see subtle and common behavioural signs, and is based on intuition and subjective decisions. Due to recent advances in wearables and artificial intel...

Recently, the monitoring of the radiofrequency electromagnetic field (RF-EMF) exposure induced by cellular networks has received a great deal of attention. In this work, a set of 70 microenvironments (MEs) located in urban and rural areas, are selected in France under on the one hand the French Beyond5G project and on the other hand the 5G expOsure...

New frequency bands, such as the mmWave at 28 GHz for fifth Generation networks in Frequency Range 2, are being introduced to accomplish the required throughput for new services such as remote surveillance, object tracking, and factory automation. These high-frequency bands are sensible to reflections and diffraction. Therefore, accurate path loss...

In this work, in situ measurements of the radio frequency electromagnetic field (RF-EMF) exposure have been conducted for an indoor massive MIMO 5G base station (BS) operating at 26-28 GHz. Measurements were performed at six different positions (at distances between 9.94 and 14.32 m from the BS), of which four were in line-of-sight (LOS) and two we...

As Vehicle-to-Everything (V2X) communication technologies gain prominence, ensuring human safety from radiofrequency (RF) electromagnetic fields (EMF) becomes paramount. This study critically examines human RF exposure in the context of ITS-5.9 GHz V2X connectivity, employing a combination of numerical dosimetry simulations and targeted experimenta...

Optical wireless communication (OWC) is emerging as a pivotal technology for next-generation broadcast networks, with visible light communication (VLC) poised to meet the escalating demands of advanced radio frequency systems. This study focuses on enhancing visible light positioning (VLP), recognized for its precision, simplicity, and cost-effecti...

UWB ranging algorithms using thresholding require careful settings that account for multipath richness. Max-peak ratio thresholds are incapable of detecting attenuated first-path components (FPCs) or risk triggering on noise. A noise-based threshold is more reliable and robust, but setting this threshold transforms the problem into distinguishing n...

p>Most spectrum surveys conducted worldwide demonstrate that the radio-electric spectrum in use at any given location and instant of time is below 25%. Current spectrum management policies and spectrum utilization inefficiency are becoming unsustainable for the future development of radio technologies and services. In this context, dynamic spectrum...

p>Most spectrum surveys conducted worldwide demonstrate that the radio-electric spectrum in use at any given location and instant of time is below 25%. Current spectrum management policies and spectrum utilization inefficiency are becoming unsustainable for the future development of radio technologies and services. In this context, dynamic spectrum...

Ultra-wideband (UWB) indoor positioning systems have the potential to achieve sub-decimeter-level accuracy. However, the ranging performance degrades significantly under non-line-of-sight (NLoS) conditions. The detection and mitigation of NLoS conditions is a complex problem and has been the subject of many works over the past decades. When localiz...

This paper presents a simulation study of non-ranging-based cooperative positioning algorithms, including absolute position differencing (APD), single-differencing (SD), single-differencing with a single satellite (SD-SS), and double-differencing (DD), for estimating the Inter-Vehicle Distance (IVD) of two static autonomous vehicles. To this end, a...

Visible light positioning (VLP) is an emerging and promising technology in the indoor positioning system (IPS) landscape that provides centimeter-level accuracy at a low cost. However, it needs to be more thoroughly investigated, particularly in industrial environments where the presence of metal imposes a significant multipath effect and degrades...

Cooperative Inter-vehicle Distance (IVD) estimation algorithms such as Absolute Position Differencing (APD), Single-Differencing (SD), and Double-Differencing (DD) are promising and cost-effective solutions thanks to Global Navigation Satellite System (GNSS) observables. These algorithms directly utilize pseudorange measurements, i.e., the estimate...

This study investigates wireless power transfer for deep in-body receivers, determining the optimal frequency, power budget, and design for the transmitter and receiver. In particular, the focus is on small, in-body receivers at large depths up to 20 cm for obese patients. This enables long-term monitoring of the gastrointestinal tract for all body...

The future of location-aided applications is shaped by the ubiquity of Internet-of-Things devices. As an increasing amount of commercial off-the-shelf radio devices support channel response collection, it is possible to achieve fine-grained position estimation at a relatively low cost. In this paper, we focus on the channel response-based positioni...

Recommender systems are commonly-used tools to assist people in making decisions. However, most research has focused on the domain of recommendations for audio-visual content and e-commerce, whereas the specific characteristics of recommendations for recipes and cooking did not receive enough attention. Since meals are often consumed in group (with...

Introduction Optogenetics has emerged as a promising technique for modulating neuronal activity and holds potential for the treatment of neurological disorders such as temporal lobe epilepsy (TLE). However, clinical translation still faces many challenges. This in-silico study aims to enhance the understanding of optogenetic excitability in CA1 cel...

Optogenetics has emerged as a promising technique for modulating neuronal activity and holds potential for the treatment of neurological disorders such as temporal lobe epilepsy (TLE). However, clinical translation still faces many challenges. This in-silico study aims to enhance the understanding of optogenetic excitability in CA1 cells and to ide...

Spectrum surveys performed worldwide demonstrate that the spectrum utilization efficiency is less than 0.25. Therefore, the traditional long-term licensed spectrum allocation by regulators is not sustainable. Although dynamic spectrum access networks allow increasing the efficiency of spectrum utilization, coexistence is still a major problem. In t...

Electronic boluses with biotelemetry capabilities enable wireless monitoring of animals’ physiological data (e.g., temperature, pH). The aim of this study was to design and experimentally validate a novel multiband (434, 868, 1400) MHz conformal patch antenna for in-body biotelemetry applications for cows. The optimal frequency band was studied pri...

Most spectrum surveys conducted worldwide demonstrate that the radio-electric spectrum in use at any given location and instant of time is below 25%. Current spectrum management policies and spectrum utilization inefficiency is becoming unsustainable for the future development of radio technologies and services. In this context, dynamic spectrum ac...

Wireless-based human activity recognition has become an essential technology that enables contact-free human-machine and human-environment interactions. In this paper, we consider contact-free multi-target tracking (MTT) based on available communication systems. A radar-like prototype is built upon a sub-6 GHz distributed massive multiple-input and...

This paper compares different low-cost sensors that can measure (5G) RF-EMF exposure. The sensors are either commercially available (off-the-shelf Software Defined Radio (SDR) Adalm Pluto) or constructed by a research institution (i.e., imec-WAVES, Ghent University and Smart Sensor Systems research group (S³R), The Hague University of Applied Scien...

Of particular interest within fifth generation (5G) cellular networks are the typical levels of radiofrequency (RF) electromagnetic fields (EMFs) emitted by ‘small cells’, low-power base stations, which are installed such that both workers and members of the general public can come in close proximity with them. In this study, RF-EMF measurements we...

The large bandwidths that are available at millimeter-wave frequencies enable fixed wireless access (FWA) applications, in which fixed point-to-point wireless links are used to provide internet connectivity. In FWA networks, a wireless mesh is created and data are routed from the customer premises equipment (CPE) towards the point of presence (POP)...

Cattle behaviour is fundamentally linked to the cows’ health, (re)production, and welfare. The aim of this study was to present an efficient method to incorporate Ultra-Wideband (UWB) indoor location and accelerometer data for improved cattle behaviour monitoring systems. In total, 30 dairy cows were fitted with UWB Pozyx wearable tracking tags (Po...

Fixed wireless access (FWA) provides a solution to compete with fiber deployment while offering reduced costs by using the mmWave bands, including the unlicensed 60 GHz one. This paper evaluates the deployment of FWA networks in the 60 GHz band in realistic urban and rural environment in Belgium. We developed a network planning tool that includes n...

Despite a lot of research about predictive maintenance for onshore and offshore windmill farms, nearly no investigation has been performed to obtain the optimal sequence in which windmills are to be served in a predefined time frame. The higher fuel costs and the increasing time pressure on maintenance jobs urge the need for optimisation, so offsho...

The utilization of millimeter wave (mmWave) technology has emerged as a key enabler for the advancement of future wireless networks. However, the widespread deployment of mmWave communication is impeded by the challenges posed by its harsh propagation characteristics. To overcome this limitation, the reconfigurable intelligent surface (RIS) is envi...

Indoor communication and positioning are significant fields of applications for indoor Internet of Things (IoT) given the rapid growth of IoT in smart cities, smart grids, and smart industries. Visible light positioning (VLP) has become more and more attractive for researchers to provide indoor location-aware IoT services. Additionally, artificial...

The large bandwidths that are available at millimeter wave (mmWave) frequency bands allow high‐throughput wireless communication systems that enable fixed wireless access (FWA) applications. In FWA networks, a stationary link is created between antennas installed at building facades or street furniture, such as lampposts. A Line‐of‐Sight (LOS) scen...

With the potential of fixed wireless access networks as an alternative to optical fiber, it is necessary to determine vegetation loss at millimeter wave frequencies. In this paper, we present vegetation loss measurement results for different types of vegetation, including trees, hedges, and forests, at frequencies ranging from 110 GHz to 170 GHz. A...

Fixed wireless access networks at millimeter wave frequencies enable an alternative to fiber-optic installations for providing high-throughput internet connectivity. In this letter, we present outdoor channel measurements at D-band frequencies ranging from 120 GHz to 165 GHz, contributing to the design of future fixed wireless access networks. We m...

This paper proposes a genetic algorithm (GA) combined with ray tracer to generate a cell-free topology of massive MIMO (mMIMO) for the optimal focusing performance serving multiple users. The realistic hardware impairment, for instance the non-ideal power amplifier, is taken into account of the system modeling and topology optimization. To the best...

The world population is aging and more and more people suffer from dementia, which makes remembering and orientation in time and space difficult. Moreover dementia has a strong negative effect on the quality of living of the people suffering from it, but also of their relatives. In this paper, we investigate if and how the playback of carefully cho...

The future of industrial location-aided applications is shaped by the ubiquity of Internet-of-Things (IoT) devices. As an increasing amount of commercial off-the-shelf radio devices support channel response collection, it is possible to achieve fine-grained position estimation at a relatively low cost. In this article, we focus on channel response-...

Within the context of the Internet of Things (IoT), many applications require high-quality positioning services. As opposed to traditional technologies, the two most recent positioning solutions: 1) ultra-wideband (UWB) and 2) (unmodulated) visible light positioning [(u)VLP] are well suited to economically supply centimeter-to-decimeter level accur...

This paper describes the exploration of the combined antenna–channel model for a horse hoof. An antenna of 25 mm × 40 mm is designed in the ISM 868 MHz band. During the characterization and design of the antenna, the dynamic and harsh environment of the horse hoof is taken into account throughout every step of the procedure because it is impossible...

Today, our society mainly relies on the energy generated by burning fossil fuels, which provides a reliable supply at an affordable price. However, this energy is not renewable and will eventually be depleted in the future. To address sustainability issues, we need to take action in all layers of our society, including our wireless access networks,...

This paper establishes an indoor distributed radar-like prototype using a sub-6 GHz massive multiple-input multiple-output (MIMO) communication system. Based on the prototype, the contact-free human tracking performance is experimentally evaluated. Instead of extracting the location related geometrical metrics (angle and distance), we propose to lo...

In this study, we develop and validate a supervised machine-learning algorithm to monitor grazing and ruminating behaviours of cattle using accelerometer sensors. The method is specifically designed for performing real-time classification on resource-constrained sensor nodes. Twenty multiparous Holstein cows were used for this study. Each cow was w...

Wireless-based human activity recognition has become an essential technology that enables contact-free human-machine and human-environment interactions. In this paper, we consider contact-free multi-target tracking (MTT) based on available communication systems. A radar-like prototype is built upon a sub-6 GHz distributed massive multiple-input and...

The constant increase in the required user capacity and the evolution of wireless network technologies impact the exposure that users experience from wireless networks. This paper evaluates various 5G network topologies regarding human exposure, mobile communication quality, and sustainability. We assess human exposure, based on a novel Exposure Ra...

Temporal interference (TI) stimulation is a technique in which two high frequency sinusoidal electric fields, oscillating at a slightly different frequency are sent into the brain. The goal is to achieve stimulation at the place where both fields interfere. This study uses a simplified version of the Hodgkin - Huxley model to analyse the different...

Indoor path loss models characterize the attenuation of signals between a transmitting and receiving antenna for a certain frequency and type of environment. Their use ranges from network coverage planning to joint communication and sensing applications such as localization and crowd counting. The need for this proposed geodesic path model comes fo...