Sökresultat

We propose new M-algorithm BCJR (M-BCJR) algorithms for low-complexity turbo equalization and apply them to severe intersymbol interference (ISI) introduced by faster than Nyquist signaling. These reduced-search detectors are evaluated in simple detection over the ISI channel and in iterative decoding of coded FTN transmissions. In the second case, accurate log likelihood ratios are essential and

This paper discusses compact node-link formulations for MPLS fast reroute optimal single path layout. We propose mathematical formulations for MPLS fast reroute local protection mechanisms. In fact, we compare one-to-one (also called detour) local protection and many-to-one (also called facility backup) local protection mechanisms with respect to minimized maximum link utilization. The optimal res

Project retrospectives can be powerful tools for project teams to collectively identify communication gaps and practices to improve for future projects. However, even if project members take the time for a retrospective, it can be hard to correctly remember and jointly discuss past events in a constructive way. Fact-based timelines that visualize a project's events offer a possible solution.

Efficient and realistic mm-wave channel models are of vital importance for the development of novel mm-wave wireless technologies. Though many of the current 60 GHz channel models are based on the useful concept of multi-path clusters, only a limited number of 60 GHz channel measurements have been reported in the literature for this purpose. Therefore, there is still a need for further measurement

Optimal data detection of a linear channel can always be implemented through the Viterbi algorithm (VA). However, in many cases of interest the memory of the channel prohibits application of the VA. A popular and conceptually simple method in this case, studied since the early 70s, is to first filter the received signal in order to shorten the memory of the channel, and then to apply a VA that ope

As new systems and applications are introduced for next-generation wireless systems, the propagation channels in which they operate need to be characterized. This paper discusses propagation channels for four types of next-generation systems: (i) distributed Multiple-Input Multiple-Output (MIMO) and Cooperative MultiPoint (CoMP), systems, which require the characterization of correlation between c

This paper presents class-D CMOS oscillators capable of an excellent phase noise performance from a very low power supply voltage. Starting from the recognition of the time-variant nature of the class-D LC tank, accurate expressions of the oscillation frequency, oscillation amplitude, current consumption, phase noise, and figure-of-merit (FoM) have been derived. Compared with the commonly used cla

We review the recent progress in dynamical and statistical downscaling approaches for west African precipitation and perform a regional climate model (RCM) intercomparison using the novel multi-model RCM data set from the Ensembles-based Predictions of Climate Changes and Their Impacts (ENSEMBLES) and African Monsoon Multidisciplinary Analyses (AMMA) projects. Present RCMs have distinct systematic

Consider the communication system model y = HFx+n, where H and F are the channel and precoder matrices, x is a vector of data symbols drawn from some lattice-type constellation, such as M-QAM, n is an additive white Gaussian noise vector and y is the received vector. It is assumed that both the transmitter and the receiver have perfect knowledge of the channel matrix H and that the transmitted sig

The performance of continuous time deltasigma modulators is limited by their large sensitivity to feedback pulse-width variations caused by clock jitter in their feedback DACs. To mitigate that effect, a dual switched- capacitor-resistor feedback DAC technique is proposed. The architecture has the additional benefit of reducing the typically high switched-capacitor-resistor DAC output peak current

Open innovation is an emerging innovation paradigm that can greatly accelerate technical knowledge innovation in software companies. The increasing importance and density of software in today’s products and services puts extensive pressure on excelling the discovery, description and execution of innovation. Despite that, software engineering literature lacks methods, tools and frameworks for full

Abstract in UndeterminedThe properties of the single-link multiple-input-multiple- output (MIMO) propagation channels have been analyzed in many studies based on extensive propagation measurements. In this letter, we extend the measurement-based analysis to dual-link MIMO propagation channels. Here, we examine interlink correlation by evaluating the correlation of eigenvectors obtained from multip

Aims/hypothesis Genetic and epidemiological studies suggest an association between gestational diabetes mellitus and type 2 diabetes. Both are polygenic multifactorial disorders characterised by beta cell dysfunction and insulin resistance. Our aim was to investigate whether common genetic variants that have previously been associated with type 2 diabetes or related phenotypes would also confer ri

Completely analyzed and closed issue reports in software development projects, particularly in the development of safety-critical systems, often carry important information about issue-related change locations. These locations may be in the source code, as well as traces to test cases affected by the issue, and related design and requirements documents. In order to help developers analyze new issu

Numerous geometric problems in computer vision involve the solu- tion of systems of polynomial equations. This is particularly true for so called minimal problems, but also for finding stationary points for overdetermined prob- lems. The state-of-the-art is based on the use of numerical linear algebra on the large but sparse coefficient matrix that represents the original equations multi- plied wi

Radio links in wireless mesh networks (WMN) can select one of several modulation and coding schemes (MCS). A MCS assignment influences links data rates and their mutual interference, and therefore should be optimized. We consider joint optimization of link rate assignment and transmission scheduling in order to maximize the minimal flow in a WMN. One of the main difficulties stems from the require

As new technologies emerge such as wearables, it opens up for new challenges, especially related to security and privacy. One such recent technology is smart glasses. The use of glasses introduces security and privacy concerns for the general public but also for the user itself. In this paper we present ongoing theoretical work which focus on privacy of the user during authentication. We propose a

A one-year study was performed at the Vavihill background station in southern Sweden to estimate the anthropogenic contribution to the carbonaceous aerosol. Weekly samples of the particulate matter PM10 were collected on quartz filters, and the amounts of organic carbon, elemental carbon, radiocarbon (C-14) and levoglucosan were measured. This approach enabled source apportionment of the total car

This book project was initiated at The Tribute Workshop in Honour of Gunnar Sparr and the follow-up workshop Inequalities, Interpolation, Non-commutative Analysis, Non-commutative Geometry and Applications, held at the Centre for Mathematical Sciences, Lund University in May and November of 2008. The resulting book is dedicated in celebration of Gunnar Sparr's sixty-fifth anniversary and more th