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This paper presents a flexible architecture suitable for performing both channel estimation and signal detection in a MIMO-OFDM downlink. Extensive hardware sharing between two tasks is achieved by algorithm and architecture co-design, where robust MMSE sliding window channel estimation and MMSE-based signal detection with symbol perturbation scheme are adopted. The proposed architecture is based
Motivation: The requirements engineering (RE) research community is aware of the importance of performing feasibility studies before starting requirements elicitation. Unfortunately, projects still frequently fail to achieve commercial success, responsibility is often unknown, and requirements engineers may be deemed responsible for mistakes made by others. Problem: There is neither empirical evid
Abstract in UndeterminedWe introduce a new method for prestack depth migration of seismic common-shot gathers.The computational procedure follows standard steps of the reverse-time migration, i.e.,downward continuation of the `source' and the `receiver' waveelds, followed by applicationof an imaging condition (e.g. zero-lag cross-correlation of these elds). In our method werst nd a sparse data rep
Manual software testing is a widely practiced verification and validation method that is unlikely to fade away despite the advances in test automation. In the domain of manual testing, many practitioners advocate exploratory testing (ET), i.e., creative, experience-based testing without predesigned test cases, and they claim that it is more efficient than testing with detailed test cases. This pap
Carrier frequency offset (CFO) synchronization is a crucial issue in the implementation of orthogonal frequency division multiplexing (OFDM) systems. Since current technology tends to implement different standards in the same wireless device, a common frequency synchronization structure is desirable. Knowledge of the physical frame and performance and cost system requirements are needed to choose
Large open and closed source organizations like Google, Facebook and Mozilla are migrating their products towards rapid releases. While this allows faster time-to-market and user f eedback, it also implies less time for testing and bug fixing. Since initial research results indeed show that rapid releases fix proportionally less reported bugs than traditional releases, this paper investigates the
Computing is no longer considered a subject area only relevant for a narrow group of professionals, but rather as a vital part of general education that should be available to all children and youth. Since making changes to national curricula takes time, people are trying to find other ways of introducing children and youth to computing. In Sweden, several current initiatives by researchers and te
Input data for communication network design/optimization problems involving multi-hour or uncertain traffic can consist of a large set of traffic matrices. These matrices are explicitly considered in problem formulations for link dimensioning. However, many of these matrices are usually dominated by others so only a relatively small subset of matrices would be sufficient to obtain proper link capa
In this paper we propose a new algorithm for solving the Learning With Errors (LWE) problem based on the steps of the famous Blum-Kalai-Wasserman (BKW) algorithm. The new idea is to introduce an additional procedure of mapping subvectors into codewords of a lattice code, thereby increasing the amount of positions that can be cancelled in each BKW step. The procedure introduces an additional noise
Abstract in UndeterminedWe introduce Gaussian wave packets in pursuit of representations of functions, in which the representation is invariant under translation, modulation, scale,rotation and anisotropic dilation. Properties of both continuous and discrete representations are discussed. For the discrete (two-dimensional) case, we develop fastalgorithms for the application of the analysis and syn
This paper presents a Sorted QR-Decomposition (SQRD) processor for 3GPP LTE-A system. It achieves energy efficiency by co-optimizing techniques, such as heterogeneous processing, reconfigurable architecture, and dual-supply voltage operation. At algorithm level, a low-complexity hybrid decomposition scheme is adopted, which switches, depending on the energy distribution of spatial channels, betwee
Open innovation (OI) means that innovation is fostered by using both external and 5 internal influences in the innovation process. In software engineering (SE), OI has existed 6 for decades, while we currently see a faster and broader move towards OI in SE. We there- 7 fore survey research on how OI takes place and contributes to innovation in SE. This study 8 aims to synthesize the research knowl
This paper presents a heterogeneous reconfigurable cell array, designed for high-throughput baseband processing of multiple-input multiple-output (MIMO) systems. To achieve high performance and energy efficiency while retaining high flexibility, the proposed architecture adopts heterogeneous and hierarchical resource deployments. Additionally, extensive vector computation enhancements and flexible
This paper presents an area/energy efficient soft-output MIMO detector that supports the detection of spatial-multiplexing (SM), spatial-diversity (SD), and space-division-multiple-access (SDMA)signals. The developed near-optimal detection algorithms for these tree modes share most of the mathematical operations to enable extensive hardware reuse. A unified VLSI architecture is accordingly designe
The F-FCSR stream cipher family has been presented a few years ago. Apart from some flaws in the initial propositions, corrected in a later stage, there are no known weaknesses of the core of these algorithms. Two variants, F-FCSR-H and F-FCSR-16, were proposed in the eSTREAM project, and F-FCSR-H v2 is one of the ciphers selected for the eSTREAM portfolio. In this paper we present a new and sever
Network re-optimization is a process that must be triggered periodically in order to improve the inefficient resource allocation of online routing heuristics due to the uncertainty of online lightpath demand arrivals and departures. Network re-optimization involves two tasks: a) finding new lightpaths for a (sub)set of current demands, i.e. rerouting, and b) migrating the current traffic to the ne
We use a 2-dimensional (2-D) Vernier gated-ring-oscillator (GRO) time-to-digital-converter (TDC) in a cascade structure (MASH), so that a larger raw quantization step can be allowed without sacrificing the final resolution performance. The 2-D approach effectively reduces the latency time under a large input, while the MASH structure provides a 2nd-order noise shaping that produces a lower in-band
Regional climate modeling is a dynamical downscaling technique applied to the results of global climate models (GCMs) in order to acquire more information on climate simulations and climate change projections. GCMs and regional climate models (RCMs) have undergone considerable development over the past few decades, and both have increased in resolution. The higher-resolution edge of RCMs compared
