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Primary and backup paths in MPLS fast reroute (FRR) may be established as shortest paths according to the administrative link costs of the IP control plane, or as explicitly calculated arbitrary paths. In both cases, the path layout can be optimized so that the maximum link utilization for a specific traffic matrix and for a set of considered failure scenarios is minimized. In this paper, we propo

In this paper, we study the performance of precoding schemes for cooperative transmission of multiple coherent base stations (BSs) that allow for overlapped clustering in a measured urban macrocellular environment at 2.66 GHz, in order to verify previous findings obtained by using simulated channel data. The evaluated precoding schemes include zero-forcing (ZF), layered virtual signal-to-interfere

In this article we present a survey of routing methods in Optical Burst Switching (OBS) networks We begin with a description of routing approaches and follow the discussion with a detailed classification of routing algorithms in OBS. Afterwards, we discuss common OBS network loss models that are frequently used in routing optimization. As examples of such application, we present a linear and a non

Coherent multi-cell cooperative transmission, also referred to as coordinated multi-point transmission (CoMP), is a promising strategy to provide high spectral efficiency for universal frequency reuse cellular systems. To report the required channel information to the transmitter in frequency division duplexing systems, limited feedback techniques are often applied. Considering that the average ch

Abstract in UndeterminedA family of iterative receivers is evaluated in terms of complexity and performance for the case of an uplink multi-user (MU) multiple-input multiple-output orthogonal frequency division multiplexing (MIMO-OFDM) system. The transmission over block fading channels is considered. The analyzed class of receivers is performing channel estimation inside the iterative detection l

The paper is devoted to modeling and optimization of reliable wireless mesh networks that employ directional antennas. We introduce two mixed-integer programming formulations that allow to simultaneously characterize routing patterns and transmission schedules. The first model allows for maximizing the minimal flow in a network. The second model involves reliability constraints and aims at minimiz

We present a study of tail-bias-current 1/f noise upconversion into 1/f(3) phase noise for both CMOS Colpitts and differential-pair LC oscillators. We focus on the incremental Groszkowski effect, i.e., the modulation of the shift in oscillation frequency induced by the higher current harmonics flowing into the LC tank of a harmonic oscillator induced by bias instabilities, as we show that there is

Designing multiple antennas in small terminals at frequency bands below 1 GHz is challenging due to severe mutual coupling among antenna elements. The severe coupling is often the result of simultaneous excitation of the fundamental characteristic mode of the terminal chassis by more than one antenna element. In this work, we propose to solve the coupling problem by manipulating the chassis struct

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

In this paper we present an improved algorithm for finding low-weight multiples of polynomials over the binary field using coding theoretic methods. The associated code defined by the given polynomial has a cyclic structure, allowing an algorithm to search for shifts of the sought minimum-weight codeword. Therefore, a code with higher dimension is constructed, having a larger number of low-w

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

Abstract in Undetermined Given an undirected graph g(V, E), a set of traffic matrices H and one additional traffic matrix h, we say that H totally dominates h if, for each capacity reservation u supporting H, u also supports h using the same routing pattern. It has been shown that if vertical bar H vertical bar = 1 = (H = {(h) over cap}, say) and g, is a complete graph, H totally dominates h if, a

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

The aim of this work has been to characterize starch based Pickering emulsions as a first step to evaluate their possible use as vehicles for topical drug delivery. A minor phase study of emulsions with high oil content has been performed. Emulsion stability against coalescence over eight weeks and after mild centrifugation treatment has been studied. The particle size, rheological properties and

Open source components can be used as one type of software component in development of commercial software. In development using this type of component, potential open source components must first be identified, then specific components must be selected, and after that selected components should maybe be adapted before they are included in the developed product. A company using open source compone