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In this paper, we compare capacity performances of three terminal dual-antenna configurations at 2.65 GHz based on extensive 2 by 2 multiple-input multiple-output (MIMO) channel measurements in an urban macrocellular environment. Both noise- and interference-limited scenarios are investigated. Our results show that, on average over the measurement route, the capacity performance is mainly determin
The development of MIMO over-the-air (OTA) test methodology is an ongoing activity in 3GPP RAN4, CTIA and EU COST Action 2100. In this paper, the focus is on the anechoic chamber approach, which uses a uniform circular array of probe antennas to replicate directional channels for the device-under- test at the array center. In particular, we study in simulation the complexity requirements of implem
We study the potential benefits of cooperative multiple-input multiple-output signaling from multiple coherent base stations with one or more mobile stations in an urban macrocellular environment. The analysis uses novel and fully coherent measurements of the channel from three base stations to a single mobile station equipped with four antennas. The observed channels are used to explore the gains
Although a number of different medium access control (MAC) schemes are adopted for wireless multi-hop networks, time division multiple access (TDMA) approaches based on a periodic frame of time slots are the most common when very high efficiency is needed in terms of use of radio and energy resources. Efficient resource usage is typically based on parallel compatible transmissions from multiple no
Distinguishers and nonrandomness detectors are used to distinguish ciphertext from random data. In this paper, we focus on the construction of such devices using the maximum degree monomial test. This requires the selection of certain subsets of key and IV-bits of the cipher, and since this selection to a great extent affects the final outcome, it is important to make a good selection. We present
Understanding and measuring security of softwarein terms of vulnerability metrics is important when reviewingand deciding between softwares. The large number of disclosedvulnerabilities will continue to expose software intensivesystems and products to attacks, and the choice of thirdparty software will affect stability and reliability of productsincorporating this software. We collect CVE da
Advances in software virtualization and network processing lead to increasing network softwarization. Software network elements running on commodity platforms replace or complement hardware components in cloud and mobile network infrastructure. However, such commodity platforms have a large attack surface and often lack granular control and tight integration of the underlying hardware and software
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.
Evaluation of Specific Absorption Rate (SAR) for multiple antenna systems is becoming important, with the upcoming deployment of LTE-Advanced. In this work, the influence of different antenna locations and antenna types was investigated for stand-alone SAR and simultaneous SAR, to provide some guidelines for antenna design in multi-antenna handsets. For simultaneous SAR, different phase shifts bet
A primary functionality of context aware applications is the retrieval of different types of context data from various context sources and adapting their behavior accordingly. In order to facilitate context aware application development, a context aware middleware must provide an effective context data management and lookup strategy. The use of a traditional index for indexing dynamic context data
Popular Abstract in Swedish Spädbarn med kolik – föräldrars upplevelse i ett kortare och ett längre perspektiv samt effekten av akupunktur på barnets skrik, ätande, avföringsmönster och sömn. Spädbarnskolik definieras som ett tillstånd där ett för övrigt friskt barn skriker och gnäller mer än tre timmar per dag mer än tre dagar i veckan. Kolik drabbar ca 10 % av nyfödda barn i västvärlden. Både bInfantile colic, involving an otherwise healthy infant crying and fussing more than three hours per day and more than three days per week, is a common problem in Western countries. Both the infant and the parents suffer during the months of persistent crying and there is a risk that the establishing of the early relationship might be disturbed. Safe and effective treatment that provides relief in
We compare LDPC block and LDPC convolutional codes with respect to their decoding performance under low decoding latencies. Protograph based regular LDPC codes are considered with rather small lifting factors. LDPC block and convolutional codes are decoded using belief propagation. For LDPC convolutional codes, a sliding window decoder with different window sizes is applied to continuously decode
Abstract—Service Level Agreements (SLA) are considered a good practice not only for IT outsourcing but also for IT management within an organisation. In this paper we study the usage of SLAs in municipal IT management. Municipal IT management traditionally involves a large organisation, often with a low IT maturity, but with high requirements on software quality and information security. In this s
Generalized Frequency Division Multiplexing (GFDM) is a recent multi carrier modulation technique that can provide low out-of-band radiation, which makes it an attractive choice for the PHY layer of cognitive radios operating in fragmented TV white spaces. Primary, incumbent signals can now be protected with a geo-location database query mechanism. Even then, sensing opportunistic users (OU) opera
We present a method for solving the previously unstudied problem of localizing a set of receivers and directions from transmitters placed far from the receivers, measuring unsynchronized time of arrival data. The same problem is present in node localization of microphone and antenna arrays. The solution algorithm using 5 receivers and 9 transmitters is extended to the overdetermined case in a stra
Software Engineering has been a fundamental part of many computing undergraduate courses for a number of years. Although many of the tools and techniques used to undertake software engineering have changed, the assessment has typically stayed the same. Students are commonly tasked with producing a number of software artefacts, for example designs using the Unified Modelling Language (UML). We rece
We studied the behavior of an iterative receiver using protograph based LDPC codes (PG-LDPCC) in an UWB short range communication system. An EXIT-Chart-Analysis is applied by means of density evolution of protographs. We show that AWGN-optimized protograph ensembles perform also well on frequency-flat UWB channels, outperform rate-compatible punctured convolutional codes (RCPC), but degrade with i
A novel code construction based on spatially coupled low-density parity-check (SC-LDPC) code chains is presented. The proposed code ensembles are described by graphs in which individual SC-LDPC code chains of various lengths serve as edges. We demonstrate that connecting several appropriately chosen SC-LDPC code chains results in improved iterative decoding thresholds compared to those of a single
