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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.

In this paper, we perform a threshold analysis of braided convolutional codes on the additive white Gaussian noise (AWGN) channel. The decoding thresholds are estimated by Monte-Carlo density evolution techniques and compared with approximate thresholds from an erasure channel prediction. The results show that, with spatial coupling, the predicted thresholds are very accurate and quickly approach

In this paper, we study sliding window decoding of braided convolutional codes (BCCs) in the context of a streaming application, where decoder error propagation can be a serious problem. A window extension algorithm and a resynchronization mechanism are introduced to mitigate the effect of error propagation. In addition, we introduce a soft bit-error-rate stopping rule to reduce computational comp

In this letter, we analyze cluster characteristics in mm wave channel characteristics, based on an indoor channel measurement campaign at 28 GHz. The spatial characteristics of clusters are analyzed, and we investigate the CDFs of the intra cluster angular spreads and the number of clusters. Also we introduce the Random Cluster Number (RCN) feature to the primary module of IMT-2020 channel model,

In this paper we present a Bayesian framework for utilizing the amplitude information of multipath components (MPCs) in radio-signal-based simultaneous localization and mapping (SLAM). The developed algorithm exploits the complex amplitudes of MPC parameters that are provided by the radio channel parameter estimator. With this information, the algorithm can adapt the probabilities of detecting fea

ExtendJ (formerly JastAddJ) is an extensible Java compiler, supporting full Java source-to-bytecode compilation. ExtendJ enables researchers and developers to easily build powerful language extensions, custom static analyses, and other tools for Java. ExtendJ is built with Reference Attribute Grammars and Aspect Oriented Programming, enabling easy extension development.

The overall system performance of massive MIMO is improved by equipping user terminals with multiple antennas. In this paper, we investigate transceiver designs for the case of a single downlink stream and in particular, we study the uplink pilot design. Moreover, we study the consequences of channel estimation errors at the base-station, and to what extent a dual-antenna terminal can get access t

In this paper, we introduce a novel hybrid multiuser multiple-input multiple-output (MU-MIMO) architecture, with an emphasis on aggressive millimeter-wave (mmWave) hardware reduction methods, omitting the beam selection stage. We propose a simplification in a 28 GHz Rotman lens, where the number of beam-ports are reduced relative to the array ports resulting in the removal of a bank of RF switches

Favorable propagation (FP) and channel hardening are desired properties in massive multiple-input and multiple-output (MIMO) systems, where nearly optimal performance is achieved with linear processing techniques, such as maximal-ratio combining. To date, these properties have primarily been analyzed for statistical channel models, or ray-based models with very specific angular parameters and dist

The performance of linear multi-user multiple-input multiple-output (MU-MIMO) systems has been extensively studied for classical statistical channel models. In contrast, there is little analysis for ray-based models, which are physically motivated, feature prominently in standards and have been experimentally validated. Thus, we present a novel analysis framework for zero forcing (ZF) and maximal

Hygroscopicity measurements of secondary organic aerosol (SOA) particles often show inconsistent results between the supersaturated and subsaturated regimes, with higher activity as cloud condensation nucleus (CCN) than indicated by hygroscopic growth. In this study, we have investigated the discrepancy between the two regimes in the Lund University (LU) smog chamber. Various anthropogenic SOA wer

European Spallation Source (ESS) will deliver neutrons at high flux for use in diverse neutron scattering techniques. The neutron source facility and the scientific instruments will be located in Lund, and the Data Management and Software Centre (DMSC), in Copenhagen. A number of detector prototypes are being developed at ESS together with its European in-kind partners, for example: SoNDe, Multi-G

This paper presents the evaluation of a method supporting the integration of packaging development into product development through the use of an assessment framework for methodologies under development. While the evaluation of the integration method itself is critical for its further development the main objective is to use this evaluation as a further testing of the assessment framework. The ass

Connected autonomous vehicles and industry 4.0 productions scenarios require ultra-reliable low-latency communication links. The varying positions of transmitter, reflecting objects and receiver cause a non-stationary time- and frequency-selective fading process. In this paper, we present the necessary hardware architecture and signal processing algorithms for a real-time geometry-based channel em

In this paper, we consider a wireless communication system where a large intelligent surface (LIS) is deployed comprising a number of small and distributed LIS-Units. Each LIS-Unit has a separate signal process unit (SPU) and is connected to a central process unit (CPU) that coordinates the behaviors of all the LIS-Units. With such a LIS system, we consider the user assignments both for sum-rate a

A coupling element is typically used to excite one of more characteristic modes of a structure to form some desired radiation properties. In particular, non-resonant coupling elements (CEs) are attractive, since it is electrically small and can be more conveniently integrated into the structure, such as the chassis of a mobile terminal. In this case, the chassis is the primary radiator of the mobi

Non-Orthogonal Multiple Access (NOMA) for a multi-user single- input single-output (SISO) setup is studied in the power and the frequency domains simultaneously. The problem of sum-bandwidth minimization under perfect channel state information is solved for various combinations of rate requirements and user pairings. In this process, an iterative Tabu-search based algorithm is applied to avoid an