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PalCom is a middleware toolkit for pervasive computing and internet-of-things. We discuss how PalCom supports exploration and live programming through three phases: exploring services, assembling them into applications, and exposing them as new services. We give an example of this workflow through the construction of a simple photo booth application.

Massive multiple-input multiple-output (MIMO) has gained a tremendous amount of attention as a key enabler of fifth-generation cellular systems. The majority of the vast literature on massive MIMO is based on fully digital processing, where each antenna element in the massive array is equipped with an up/down-conversion chain. Unlike previous works, we present a suite of greedy algorithms using pu

Favorable propagation (FP) and channel hardening (CH) are desired properties in massive multiple-input multiple-output (MIMO) systems. To date, these properties have primarily been analyzed for classical statistical channel models, or ray-based models with very specific angular parameters and distributions. This paper presents a thorough mathematical analysis of the asymptotic system behavior for

A low-cost microstrip patch antenna array is proposed in this paper for automotive radar applications in ISM 24 GHz band. The elements of the center-fed array are connected in series to make a compact design with low complexity by obviating Wilkinson power divider. This approach also helps to reduce the dielectric losses of the array. A full-wave electromagnetics (EM) software EMPIRE XPU is used i

We present and analyze a new approach to improve energy efficiency in cellular IoT devices. The new approach consists of employment of ultra low power wake-up receivers in combination with robust non-coherent modulation. The results show that we can achieve very competitive power consumption, reducing it by up to 50 times, compared to two conventional power saving solutions we use as references. T

We envision the use of large intelligent surface (LIS) technology, which is a promising concept that goes beyond massive multiple-input multiple-output (MIMO), for positioning applications due to its ability to focus energy in the 3D space. The Cramér-Rao lower bounds (CBLBs) for positioning using a LIS which can resolve amplitude and phase with full resolution have already been determined in the

We present a new type of wireless access infrastructure consisting of a fabric of dispersed electronic circuits and antennas that collectively function as a massive, distributed antenna array. We have chosen to name this new wireless infrastructure 'RadioWeaves' and anticipate they can be integrated into indoor and outdoor walls, furniture, and other objects, rendering them a natural part of the e

This paper proposes a pragmatic methodology to characterize mutual coupling in uniform linear arrays (ULAs). The classical coupling model used in the literature of multiple input multiple output (MIMO) antenna arrays is based on impedance parameters, resulting valid only for electromagnetically small antennas, e.g. short dipole. To test the robustness and accuracy of the proposed coupling model we

Internet-of-things systems are difficult to understand and debug due to their distributed nature and weak connectivity. We address this problem by using relational reference attribute grammars to model and analyze IoT systems with unreachable parts. A transitive device-dependency analysis is given as an example.

This article presents a shared vision among stakeholders across the value chain on the use of radio positioning and sensing for road safety in the 5G ecosystem. The key enabling technologies and architectural functionalities are explored, focusing on the extremely stringent localization and communication requirements. A case study for joint radar and communication using experimental data showcases

Most recent programming languages include a collection framework as part of their standard library (or runtime). Examples are Java, C#, Python and Ruby. The Java Collection Framework provides a number of collection classes, some of which implement the same abstract data type, which makes them interchangeable. Developers can therefore choose between several functionally equivalent options. Since co

Background: Prototyping is an established practice for user interface design and for requirements engineering within agile software development, even so there is a lack of theory on prototyping. Aims: The main research objective is to provide a means to categorise prototyping instances, in order to enable comparison and reflection of prototyping practices. Method: We have performed a systematic ma

Large-scale software engineering is a collaborative effort where teams need to communicate to develop software products. Managers face the challenge of how to organise work to facilitate necessary communication between teams and individuals. This includes a range of decisions from distributing work over teams located in multiple buildings and sites, through work processes and tools for coordinatin

Cellular-connected unmanned aerial vehicles (UAVs) have recently attracted a surge of interest in both academia and industry. Understanding the air-to-ground (A2G) propagation channels is essential to enable reliable and/or high-throughput communications for UAVs and protect the ground user equipments (UEs). In this contribution, a recently conducted measurement campaign for the A2G channels is in

Power control is becoming increasingly essential for the fifth-generation (5G) and beyond systems. An example use-case, among others, is the unmanned-aerial-vehicle (UAV) communications where the nearly line-of-sight (LoS) radio channels may result in very low signal-to-interference-plus-noise ratios (SINRs). The authors in (Chiang et al., 2007) proposed to efficiently and reliably solve this kind

Millimeter-Wave (mmWave) massive multiple-input multiple-output (MIMO) has been considered as a key enabler for the fifth-generation (5G) communications. It is essential to design and test mmWave 5G devices under various realisticscenarios since the radio propagation channels pose intrinsic limitations on the performance. This requires emulating realistic dynamic mmWave channels in a reproducible

In platform software ecosystems, organizations partner and innovate together. Success and innovation depend on managing complex sets of business relationships and stakeholders and using a requirements-selection process. We describe the associated challenges and strategies from the study of two large proprietary platform ecosystems.

Internet-of-Things (IoT) systems consist of spatially distributed interacting devices. In contrast to desktop applications, IoT systems are always running and need to deal with unresponsive devices and weak connectivity. In this thesis, we propose techniques for simplifying the development of such systems. The work addresses IoT systems organised as reusable services connected by compositions. We

We present a belief propagation (BP) algorithm with probabilistic data association (DA) for detection and tracking of specular multipath components (MPCs). In real dynamic measurement scenarios, the number of MPCs reflected from visible geometric features, the MPC dispersion parameters, and the number of false alarm contributions are unknown and time-varying. We develop a Bayesian model for specul