The advent of Low-Power Wide Area Networks has enabled significant developments of the IoT ecosystem. Long range communication using low power is now feasible and offers connectivity to remote areas where cellular network is not available. Therefore, new application scenarios have emerged, such as smart cities, smart metering and more, which are attracting a lot of attention from both research and industry. Beside the aforementioned popular scenarios, Low-Power Wide Area Networks have started to be used in wearable systems scenarios as well. In this position paper, we pose some questions regarding the Human Computer Interaction aspects of Low-Power Wide Area Networks which will help them integrate in Ubiquitous Computing applications. We illustrate by a wearable system, which is based on an foot gesture interface, a Low-Power Wide Area Network, and an Neural Network classifier. The discussion is based on the state of art of foot interfaces and highlights open issues and challenges. 

Low-Power Wide Area Networks (LPWANs) has enriched the IoT ecosystem with new features and application scenarios. LPWANs offer long range communication and can be used to connect devices that are divided by long distances and offer connectivity to remote areas where cellular networks are not accessible. They utilize their long range, low-power robust communication to enable popular application scenarios, such as smart cities and smart agriculture.

However, the environment that most of these networks operate in is unlicensed spectrum, which might be crowded and noisy due to the co-existence of other networks and technologies that operate in the same frequency band. Therefore, one of the goals of this thesis is to investigate the degree of robustness in LPWANs and propose seamless mechanisms that ensure robust communication in case of high degree of interference. Another goal is to support application scenarios in sports technology and health, which require robust and long-range communication. Hence, the second goal of this thesis is to explore how to take advantage of the robust communication that LPWANs offer, and use it in application scenarios in sports technology and health.

To realize the aforementioned goals, this thesis is quantifying the tolerance level of LPWANs in high interference level environments and suggests methods that will make the co-existence of these networks more sustainable. It also demonstrates that LPWANs can be used in healthcare and safety contexts with a use case of a long-range emergency system. Finally, this thesis provides evidence that LPWAN is a good fit for sports technology applications as it presents a use case where long range time synchronization is offered for a kayak training application using LPWAN.

Energisnåla långdistansnätverk, på engelska Low-Power Wide Area Networks (LPWAN), har berikat IoT-ekosystemet med nya funktioner och möjliga tillämpningsområden. LPWAN erbjuder trådlös kommunikation med lång räckvidd och kan användas för att ansluta apparater som är långt ifrån varandra samt erbjuder uppkoppling till avlägsna områden där mobilnätet inte är tillgängligt. De använder sin långa räckvidd, låga strömförbrukning, och robusta kommunikation till att möjliggöra populära tillämpningsområden, så som smarta städer och smart jordbruk.

Dock använder de flesta av dessa nätverk olicensierat spektrum, vilket kan vara trångt och fullt med andra nätverk och tekniker som använder samma frekvensband. Därför är ett av målen med denna avhandling att undersöka graden av robusthet hos LPWANs och föreslå smidiga mekanismer som säkerställer robust kommunikation även vid stora störningar från andra nätverk. Ett annat mål är att stödja applikationsscenarier inom sportteknologi och hälsa, vilka kräver robust kommunikation med lång räckvidd. Därför är det andra målet med denna avhandling att utforska hur man kan dra nytta av den robusta kommunikationen som LPWAN erbjuder och använda den i tillämpningar inom idrottsteknologi och hälsa.

För att möta de ovannämnda målen, så börjar denna avhandling med att kvantifiera toleransnivån hos LPWAN när de använder spektrum med mycket interferens, för att sedan föreslå nya metoder som gör samverkan mellan dessa nätverk mer hållbar. Avhandlingen visar också att LPWAN kan användas i hälso- och säkerhetssammanhang med ett användarfall på ett personlarmsystem med lång räckvidd. Slutligen ger denna avhandling bevis på att LPWAN passar bra till applikationer inom sportteknologi eftersom ett användarfall presenteras där tidssynkronisering över långa avstånd implementerats i ett kajakträningsprogram med hjälp av LPWAN.

TSCH-over-LoRa is a long range and reliable IPv6 multi-hop solution that aims atcombining the reliability of TSCH (Time-Slotted, Channel Hopping) together withthe long range capabilities of LoRa. TSCH-over-LoRa brings mesh IPv6 network-ing to LoRa devices, enabling the use of standard protocols (such as RPL, UDP, andCoAP) and long range operation to TSCH/6TiSCH industrial wireless IoT networks.We design, implement, and integrate TSCH-over-LoRa into the TSCH/6TiSCH net-working stack of the Contiki-NG operating system and experimentally demonstrateits compatibility with higher-level protocols and its resilience to interference.

Due to their popularity, large coverage areas, and diversity of radio technologies, Low Power Wide Area Networks (LPWAN) will experience high levels of cross-technology interference. In this work, we investigate the impact of LoRa interference on IEEE 802.15.4 (Wi-SUN) networks. Using hardware experiments, we characterize the interaction between these two very different radio technologies. In particular, we observe that the IEEE 802.15.4 Clear Channel Assessment (CCA) mechanism does not reliably detect interfering LoRa transmissions. We therefore propose an enhanced CCA mechanism based on a Multi-Layer Perceptron classifier and show that it significantly reduces the number of unsuccessful transmissions, while remaining compatible with the IEEE 802.15.4 standard.

Low-Power Wide-Area Network (LPWAN) is an emerging technology in IoT which is utilized in use cases like smart cities and smart agriculture. LPWAN offers new features to wearable systems and therefore introduces new application scenarios. Long range communication is already used in application scenariosm such as elderly monitoring, localization, sportsm etc. We demonstrate how LPWAN wearables can operate by using energy-harvesting means and be battery-free. This preliminary study with real experiments illustrates how the LoRa radio is able to operate by a combination of solar and mechanical energy on a smart shoe prototype outdoors. The results indicate that the activity can influence the harvest rate.

We present some preliminary results on LoRaWAN and IEEE 802.15.4- SUN interference in urban environments. The results are based on a simple simulation that is parameterized using PHY layer measurements of controlled interference scenarios

The rapid growth of new radio technologies for Smart City/Building/Home applications means that models of cross-technology interference are needed to inform the development of higher layer protocols and applications. We systematically investigate interference interactions between LoRa and IEEE 802.15.4g networks. Our results show that LoRa can obtain high packet reception rates, even in presence of strong IEEE 802.15.4g interference. IEEE 802.15.4g is also shown to have some resilience to LoRa interference. Both effects are highly dependent on the LoRa radio's spreading factor and bandwidth configuration, as well as on the channelization. The results are shown to arise from the interaction between the two radios' modulation schemes. The data have implications for the design and analysis of protocols for both radio technologies.

Advances in low power wireless communication have resulted in new radio technologies that can achieve long distance communication in energy efficient ways. An emerging problem in this scenario is interference between networks that share the same medium. The fact that these networks have a long transmission range increases the possibility of interference even more. Thus the investigation of how different networks can share the medium independently in a optimal way becomes an essential requirement for the IoT vision. In this poster, we present the first step of this investigation, which is measuring how LoRa and IEEE 802.15.4g PHY layers interfere.