Maarten Weyn

University of Antwerp / iMinds · Applied Engineering

This paper presents the DASH7 Alliance Protocol 1.0. It is an industry alliance standard for wireless sensor and actuator communication using the unlicensed sub-1 GHz bands. The paper explains its historic relation to active RFID standards ISO 18000-7 for 433 MHz communication, the basic concepts and communication paradigms of the protocol. Since t...

This paper discusses the experiences gained from designing, deploying and maintaining low-power wireless sensor networks in three geothermally active remote locations in Iceland. The network was deployed to assist researchers in collecting soil temperature data which would help them investigate the impact of global warming on (sub)Arctic climate an...

The EmoWear dataset provides a bridge to explore Emotion Recognition (ER) via Seismocardiography (SCG), the measurement of small cardio-respiratory induced vibrations on the chest wall through Inertial Measurement Units (IMUs). We recorded Accelerometer (ACC), Gyroscope (GYRO), Electrocardiography (ECG), Blood Volume Pulse (BVP), Respiration (RSP),...

Wireless sensor networks (WSNs) have received great interest due to their scalability, energy efficiency, and low-cost deployment. By utilizing multi-hop communication, WSNs can cover a wide area using low transmission power without the need for any communication infrastructure. Traditionally, WSNs rely on store-and-forward routing protocols and Ti...

The temperature difference between soil and air holds the potential to generate energy to power many low-power IoT devices. However, there is a lack of studies in the literature that explore the nuances of soil-air thermal energy harvesting. This paper offers a comprehensive discussion on soil-air thermal energy harvesting. We engineer a custom Soi...

In this paper, we study a multiuser multiple-input single-output (MISO) machine type communication (MTC)-enabled intelligent reflecting surface (IRS) system, where a multi-antenna access point (AP) transmits information symbols to a set of Internet of Things (IoT) users with short packet transmission. In particular, the total energy efficiency (EE)...

Location data is an important piece of information in many Internet of Things (IoT) applications. Global Navigation Satellite Systems (GNSS) have been established as the standard for large-scale localization. However, the rapidly increasing need to locate IoT devices in recent years has exposed several shortcomings of traditional GNSS approaches. T...

For decades, Global Navigation Satellite Systems (GNSS) have been dominant in the Positioning, Navigation and Timing (PNT) market. Improvements have been made to the design and implementation throughout the years. Recently, however, growing demand has emerged for alternative PNT solutions. These solutions should overcome several shortcomings in the...

In recent years, localization with LoRaWAN has been introduced as a potential low-power alternative to GNSS. However, previous research has shown that these methods produce large estimation errors, which is not desirable for IoT applications that depend on accurate location information. Therefore, a thorough analysis of the trade-offs between GNSS...

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...

Energy harvesting is an effective technique for prolonging the lifetime of Internet of Things devices and Wireless Sensor Networks. In applications such as environmental sensing, which demands a deploy-and-forget architecture, energy harvesting is an unavoidable technology. Thermal energy is one of the most widely used sources for energy harvesting...

In this paper, we propose a comprehensive low-power and low-cost Angle of Arrival (AoA) estimation system. The proposed system consists of a hardware architecture and an AoA estimation algorithm. The proposed hardware captures the phase values of the received signal and transmits them to the nearest LoRaWAN gateway. In the cloud, an AoA estimation...

In recent years, greenhouse-based precision agriculture (PA) has been strengthened by utilization of Internet of Things applications and low-power wide area network communication. The advancements in multidisciplinary technologies such as artificial intelligence (AI) have created opportunities to assist farmers further in detecting disease and poor...

Most applications and services of Cooperative Intelligent Transport Systems (C-ITS) rely on accurate and continuous vehicle location information. The traditional localization method based on the Global Navigation Satellite System (GNSS) is the most commonly used. However, it does not provide reliable, continuous, and accurate positioning in all sce...

Edge computing is one of the key features of the 5G technology-scape that is realizing new and enhanced automotive use cases for improving road safety and emergency response management. Back Situation Awareness (BSA) is such a use case that provides an advance notification to the vehicles of an arriving emergency vehicle (EmV). This paper presents...

Precision Agriculture (PA) is a management strategy that utilizes communication and information technology for farm management. It is a key to improve productivity by using the best agricultural practices and optimal usage of resources. Agriculture faces diverse challenges due to soil degradation, climate variation, and increasing costs. To unfold...

Ultra-Wideband (UWB) is a Radio Frequency technology that is currently used for accurate indoor localization. However, the cost of deploying such a system is large, mainly due to the need for manually measuring the exact location of the installed infrastructure devices (“anchor nodes”). Self-calibration of UWB reduces deployment costs, because it a...

Inertial Measurement Units (IMUs) are frequently implemented in wearable devices. Thanks to advances in signal processing and machine learning, applications of IMUs are not limited to those explicitly addressing body movements such as Activity Recognition (AR). On the other hand, wearing IMUs on the chest offers a few advantages over other body pos...

A first test of the field capabilities of a novel in situ sampling technique combining active and passive sampling (APS) was conducted in the sea. The proof-of-concept device uses a pump to draw water into a diffusion cell where dissolved target substances are accumulated onto sorbents which are selective for different classes of contaminants (i.e....

In this paper, we present an experimental analysis of the Angle of Arrival (AoA) estimation accuracy in an indoor environment. We utilized an AoA estimation system that is suitable for Low Power Wide Area Network (LPWAN) technologies. The AoA estimation system constituted 8 antenna elements that are distributed as Uniform Linear Array(ULA) antenna....

The future of transportation systems is going towards autonomous and assisted driving, aiming to reach full automation. There is huge focus on communication technologies expected to offer vehicular application services, of which most are location-based services. This paper provides a study on localization accuracy limits using vehicle-to-infrastruc...

The ability to monitor associations between wild animals is essential for understanding the processes governing gene transfer, information transfer, competition, predation and disease transmission. Until recently, such insights have been confined to large, visible or captive animals. However, the rapid development of miniature sensors for consumer...

During the last decade, the concept of smart cities is gaining popularity, and many cities all around the globe are adopting it. Lately, the Smart Pedestrian Crossing (SPC) idea has become an important part of the smart city concept. The main objective of the SPC is to achieve a safe and smooth traffic flow of pedestrians and vehicles in the smart...

In this paper, we introduce a comprehensive angle of arrival (AoA) estimation solution for the long range (LoRa) communication network. Termed the LoRa array (LoRay), the proposed system constitutes hardware and software solutions to estimate the AoA of the received signals in real life urban environments. The hardware solution is based on converti...

The authors wish to make the following corrections to this paper [...]

Low Power Wide Area Networks (LPWAN) have the ability to localize a mobile transmitter using signals of opportunity, as a low power and low cost alternative to satellite-based solutions. In this paper, we evaluate the accuracy of three localization approaches based on the Received Signal Strength (RSS). More specifically, the performance of a proxi...

In contrast to accurate GPS-based localization, approaches to localize within LoRaWAN networks offer the advantages of being low power and low cost. This targets a very different set of use cases and applications on the market where accuracy is not the main considered metric. The localization is performed by the Time Difference of Arrival (TDoA) me...

The majority of radio frequency crowd estimation systems are tested with at most a few tens of human individuals. At the same time, they are particularly useful for crowd safety management for events with hundreds or thousands of visitors. We deployed our passive crowd estimation system in two environments at a 400 000-visitor music festival. This...

5G has opened up possibilities of introducing new use cases and business models that could not be perceived before. In the context of public safety, 5G offers immense opportunities towards enhancing mission success and situation awareness during emergency management. This paper introduces Back-Situation Awareness (BSA) application enabling early wa...

The research domain of device-free localization (DFL) is centered on the study of localization techniques which do not require targets to wear any kind of device. Passive radio mapping or passive fingerprinting is an example of a training-based DFL technique which uses the impact of a human target on radio frequency (RF) communication between stati...

The spectrum of Internet of Things (IoT) applications is exponentially growing, driving the demand for better energy performance metrics. In conjunction, Low Power Wide Area Networks (LPWAN) have evolved as long-range connectivity enabler with low management cost. The integration of LPWAN communication assists in reliable IoT operation with extende...

This paper analyses the experimentally-assessed dual-polarized (DP) mobile channel in a tunnel environment under traffic conditions. We investigate the impact of antenna polarization and radiation pattern on the non-stationary vehicle-to-infrastructure (V2I) channel. Basic channel evaluation metrics are examined including path gain, co-polarization...

Multiple Radio Access Technology (multi-RAT) communication with Low Power Wide Area Networks (LPWAN) significantly increases the flexibility of Internet of Things (IoT) applications. Location-based services that build upon such a multimodal communication architecture are able to switch to an optimal localization method depending on the constraints...

Recently, Semtech has released a Long Range (LoRa) chipset which operates at the globally available 2.4 GHz frequency band, on top of the existing sub-GHz, km-range offer, enabling hardware manufacturers to design region-independent chipsets. The SX1280 LoRa module promises an ultra-long communication range while withstanding heavy interference in...

Apart from long range communication, Low Power Wide Area Networks (LPWAN) are used to locate Internet of Things (IoT) devices. With hundreds of networks being deployed in a short amount of time, NarrowBand IoT (NB-IoT) is stealing the LPWAN market shares from its competitors. The deep indoor coverage of NB-IoT guarantees the energy-efficient commun...

Organisers of events attracting many people have the important task to ensure the safety of the crowd on their venue premises. Measuring the size of the crowd is a critical first step, but often challenging because of occlusions, noise and the dynamics of the crowd. We have been working on a passive Radio Frequency (RF) sensing technique for crowd...

The creation of an automatic crowd estimation system capable of providing reliable, real-time estimates of human crowd sizes would be an invaluable tool for organizers of large-scale events, particularly so in the context of safety management. We describe a set of experiments in which we installed a passive Radio Frequency (RF) sensor network in di...

Initially, Low Power Wide Area Networks (LPWAN) were designed for communicating small sensor readings in a metropolitan area. With the rapidly increasing number of Internet of Things (IoT) devices, however, there is a growing need to localize these devices with LPWAN. Given the extreme battery lifetime requirements of IoT-enabled devices, we want t...

Location-based services are an essential aspect of many Internet of Things (IoT) applications. Due to low power requirements that these applications impose on their end devices, classic GNSS solutions are replaced by wireless localization via Low Power Wide Area Networks (LPWAN), e.g. Time Difference of Arrival (TDoA) localization with LoRaWAN. Usu...

The usage of Low-Power Wide Area Networks (LPWAN) is increasing rapidly in many sectors of Internet of Things (IoT) applications. Long Range (LoRa) Wide Area Network (LoRaWAN) is a LPWAN, which has a long-range, low-cost and acts as a connectivity enabler. Most of the applications with real-time requirements, need reliable communication. This can b...

The technology development in wireless sensor network (WSN) offers a sustainable solution towards precision agriculture (PA) in greenhouses. It helps to effectively use the agricultural resources and management tools and monitors different parameters to attain better quality yield and production. WSN makes use of Low-Power Wide-Area Networks (LPWAN...

In this paper, we present a new Angle of Arrival (AoA) estimation system for Internet of Things (IoT) applications. The proposed system utilizes the received signal strength (RSS) to estimate the AoA of the received signal in the 868 MHz frequency band. The system consists of two subsystems: Subsystem 1 utilizes a Rotman lens to provide analog beam...

In this paper, we present two localization algorithms that exploit the Angle of Arrival (AoA) parameters of the received signal. The proposed ANGular Location Estimation (ANGLE) algorithms utilize a probabilistic model to describe the angular response of the received signal. Consequently, the ANGLE algorithms can estimate the location of a transmit...

Location-based services are an essential aspect of many Internet of Things (IoT) applications. Due to low power requirements that these applications impose on their end devices, classic GNSS solutions are replaced by wireless localization via Low Power Wide Area Networks (LPWAN), e.g. Time Difference of Arrival (TDoA) localization with LoRaWAN. Usu...

Low-Power Wide Area Networks (LPWAN) for resilient Internet of Things (IoT) ecosystems come with unprecedented cost for the minimal load of communication. Long Range (LoRa) Wide Area Network (LoRaWAN) is a LPWAN which has a long range, low bit rate and acts as a connectivity enabler. However, making an efficient collaborative service of clock synch...

In smart cities, a myriad of devices is connected via Low Power Wide Area Networks (LPWAN) such as LoRaWAN. There is a growing need for location information about these devices, especially to facilitate managing and retrieving them. Since most devices are battery-powered, we investigate energy-efficient solutions such a Received Signal Strength (RS...

Most of the vehicular industry applications require precise, reliable, and secure positioning with cm level accuracy. IEEE 802.11p and LTE-V exploit technological solutions to achieve communication vehicle to vehicle V2V, vehicles to infrastructure V2I, vehicle to pedestrians V2P, or vehicle to everything V2X. This paper presents the achievable loc...

The requirement of active localization techniques to attach a hardware device to the targets that need to be located can be difficult or even impossible for certain applications. For this reason, there has been an increasing interest in tagless or device-free localization (DFL) approaches. In particular, the research domain of RF-based device-free...

Imec is building its Smart Highway testbed for vehicle-to-everything (V2X) communication, located in Antwerp, Belgium. The Smart Highway test site is being built on the E313/E34 highway and shall be extended to the (urban) road network ensuring a connection to the Antwerp / imec Smart Cities initiative providing a mixed environment for testing vari...

In this paper, we present a low cost Angle of Arrival (AoA) estimation unit that can be used as an Internet of Things (IoT) receiver and provides AoA estimations of the received signals. This AoA unit built based on converting multiple individual low cost Software Defined Radio (SDR) into a single SDR with multiple RF-channels. The proposed hardwar...

Biological research often tracks animal using collars containing a wireless sensor that transmit telemetry or positional data. However, when dealing with small animals, the size and weight of conventional telemetry is often an obstruction and can alter animal behavior. In this study we take a look at the the viability of Bluetooth Low Energy (BLE)...

In this paper we present a new algorithm to synchronize multiple individual receiving sub-array antennas to form an augmented array antenna system. This augmented array antenna has a large antenna aperture that can be used for angle of arrival (AoA) estimations and it provides a better AoA estimation accuracy than the individual sub-array antennas....

Location-based services play an important role in Internet of Things (IoT) applications. However, a trade-off has to be made between the location estimation error and the battery lifetime of an IoT device. As IoT devices communicate over Low Power Wide Area Networks (LPWAN), signal strength localization methods can use the existing communication li...

The Internet of Things (IoT) has caused the modern society to connect everything in our environment to a network. In a myriad of IoT applications, smart devices need to be located. This can easily be done by satellite based receivers. However, there are more energy-efficient localization technologies, especially in Low Power Wide Area Networks (LPW...