Analysis of Network Parameters Influencing Performance of Hybrid Multimedia Networks

Multimedia networks is an emerging subject that currently attracts the attention of research and industrial communities. This environment provides new entertainment services and business opportunities merged with all well-known network services like VoIP calls or file transfers. Such a heterogeneous system has to be able satisfy all network and end-user requirements which are increasing constantly. Therefore the simulation tools enabling deep analysis in order to find the key performance indicators and factors which influence the overall quality for specific network service the most are highly needed. This paper provides a study on the network parameters like communication technology, routing protocol, QoS mechanism, etc. and their effect on the performance of hybrid multimedia network. The analysis was performed in OPNET Modeler environment and the most interesting results are discussed at the end of this pape

Hands-On Experience with UWB : Angle of Arrival Accuracy Evaluation in Channel 9

This paper evaluates IEEE 802.15.4z standard- compliant NXP SR040 and SR150 chips in Angle of Arrival (AoA) capabilities in Channel 9 (7.737—8.237 GHz) of the Ultra-WideBand (UWB) spectrum. Due to the shorter wavelength, higher frequencies may encounter certain limitations when it comes to harsh environments, as more reflections and multipath propagation can occur. Furthermore, they also can be affected by their enclosure used to protect the electronics in such an environment, which needs to be taken into account during product design. This work presents the results of the evaluation measurement scenario relatable to real-life use cases and concludes potentially valuable insight important for consideration when creating a new UWB product. Besides a basic overview of the theoretical estimation of AoA by Time Difference of Arrival (TDoA) and Phase Difference of Arrival (PDoA), and the evaluation of the corresponding results, the main contribution is the repeatable topology considered for the conducted measurements. The presented results allow vendors to compare their solutions with the various radio chips or antenna configurations.acceptedVersionPeer reviewe

Performance Assessment of Reinforcement Learning Policies for Battery Lifetime Extension in Mobile Multi-RAT LPWAN Scenarios

Considering the dynamically changing nature of the radio propagation environment, the envisioned battery lifetime of the end device (ED) for massive machine-type communication (mMTC) stands for a critical challenge. As the selected radio technology bounds the battery lifetime, the possibility of choosing among several low-power wide-area (LPWAN) technologies integrated at a single ED may dramatically improve its lifetime. In this paper, we propose a novel approach of battery lifetime extension utilizing reinforcement learning (RL) policies. Notably, the system assesses the radio environment conditions and assigns the appropriate rewards to minimize the overall power consumption and increase reliability. To this aim, we carry out extensive propagation and power measurements campaigns at the city-scale level and then utilize these results for composing real-life use-cases for static and mobile deployments. Our numerical results show that RL-based techniques allow for a noticeable increase in EDs’ battery lifetime when operating in multi-RAT mode. Furthermore, out of all considered schemes, the performance of the weighted average policy shows the most consistent results for both considered deployments. Specifically, all RL policies can achieve 90 % of their maximum gain during the initialization phase for the stationary EDs while utilizing less than 50 messages. Considering the mobile deployment, the improvements in battery lifetime could reach 200 %.acceptedVersionPeer reviewe

Optimizing NB-IoT Communication Patterns for Permanently Connected mMTC Devices

The new types of industry-driven applications that need to be supported by low-power wide-area networks (LP-WANs), such as remote control or metering of devices within the massive machine-type infrastructures (e.g., Smart Grids), require a permanent connection to the remote server. In addition, there is also a shift in the communication paradigm, as the user equipment (UE) nodes are queried in regular and frequent intervals. Notably, the presence of this type of traffic may drastically deteriorate the performance of LPWAN technologies initially developed to support conventional use-cases characterized by non-synchronized transmissions. Though none of the LPWAN technologies is inherently designed to handle such demanding communication patterns, the narrowband Internet of things (NB-IoT) still stands for the best candidate as it operates within the license frequency spectrum. To optimize the delay performance of both types of traffic coexisting at the NB-IoT air interface, we propose an approach based on spreading the message transmission time instants of regular and stochastic traffic. We show an optimal value of the spreading interval minimizing the message transmission delay of regular traffic and propose a mathematical model to estimate its value. By parameterizing the model using a detailed measurements campaign of NB-IoT, we show that the optimal value of spreading interval and associated mean message delay is a linear function of the number of UEs. We report these values for a wide range of UEs in the coverage area of the NB-IoT base station and show that conventional stochastic traffic does not influence regular traffic performance.acceptedVersionPeer reviewe

Experimental Quality Assessment of Cellular Networks and their Utilization for UAV Services

Unmanned aerial vehicles (UAVs) have attracted significant attention. Many potential applications are predicted to bring abundant business opportunities in the next decade thanks to the ubiquitous connectivity of the 4G and 5G cellular networks. Unlike terrestrial deployments, airborne infrastructures have diverse attributes, e.g., increased deployment flexibility, line-of-sight (LoS) connections, and controlled mobility. These attributes bring new research questions and challenges, including LoS dominant ground channels together with increased aerial-terrestrial network interference, the exploitation of the degree of freedom (DoF) provided by the UAV mobility, and the different and tighter quality of service (QoS) requirements for purposes of unmanned traffic management (UTM). Further challenges stem from existing infrastructure oriented towards service availability in low altitudes and low data transfer costs. A key challenge in this context is to achieve and guarantee sufficient service reliability in all altitudes where UTM is planned to be used. Obtained results from the measurement campaign at Twente airport indicate the performance of the 4G cellular network is stable and equals the terrestrial use cases up to 60 m of altitude. However, if the altitude increases more, the network performance degrades significantly. In detail, the analysis revealed the fact the performance drop is significant, especially for downlink transmissions (from ground to UAVs), as the strong interference and connection outages were observed in increased numbers.Peer reviewe

Advanced wireless m-bus platform for intensive field testing in industry 4.0-based systems

Current forecasts predict that the Industrial Internet of Things (IIoT) will comprise about 10 billion devices by 2020. Because of its unique and novel demands, the emerging concepts of Industry 4.0 and SmartGrid networks have recently been coined and are now well established in the technical speech. In this work, we propose a newly developed multi-platform software tool aimed at testing the capabilities of Wireless MBus (WM-Bus) networks via simulating sensor-like behavior in uni-directional communication with a remote data concentrator. Building on our developed machine-type communication gateway (MTCG) able to receive WM-Bus data, we extend the set of features and introduce new machine-type communication device (MTCD) capable of emulating the corresponding data transmissions. As utility companies lack these features, our software implementation and hardware design open the door to initial verification of WM-Bus-based data transmissions for them without the need for investing into expensive development and certification of smart meters, where WM-Bus is utilized for data transmissions.Peer reviewe

Playfulness and progression in technology-enhanced social experiences between nearby strangers

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LWM2M for Cellular IoT : Protocol Implementation and Performance Evaluation

With the growing number of IoT devices, numerous IoT protocols are being developed to provide the market with options based on product requirements. With the release of cellular IoT (CIoT) technologies in the Czech Republic, recently LTE Cat-M, the focus shifts towards not only satisfying the requirements of the device application but also minimizing the generated traffic and overall co-existence of many devices under one cell. It led to the modification of the existing and the creation of new IoT protocols designed to generate as little overhead traffic as possible while adopting the existing well- known communication schemes. Namely, the new UDP-based protocol for IoT, LWM2M strives to be the alternative to the well-established IoT protocols used outside of CIoT. This paper explains the communication principles and capabilities of the well-established IoT protocols with a heavy focus on the LWM2M protocol. Further, it describes difficulties during user implementation of the LWM2M protocol. Furthermore, two carefully designed scenarios are used to compare the differences among these protocols, focusing on generated overhead as it is subject to a fee paid to the network operators within the CIoT networks.Peer reviewe