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This paper presents an analysis on energy dissipation of a digital half band filters operated in the the sub-threshold (sub-VT ) region with throughput constraints. The degradation of speed in the sub-VT domain is counteracted by unfolding the architectures. A filter is implemented in a basic 12-bit and its various unfolded structures. The designs are synthesized in a 65 nm low-leakage high-thresh

In very-large multiple-input multiple-output (MIMO) systems, the BS (base station) is equipped with very large number of antennas as compared to previously considered systems. There are various advantages of increasing the number of antennas, and some schemes would require handling large matrices for joint processing (pre-coding) at the base station. The dirty paper coding (DPC) is an optimal pre-

Wireless communication using very-large multiple-input multiple-output (MIMO) antennas is a new research field, where base stations are equipped with a very large number of antennas as compared to previously considered systems. In theory, as the number of antennas increases, propagation properties that were random before start to become deterministic. Theoretical investigations with independent id

This paper presents a highly parallelized MIMO signal detection algorithm targeting vector-based reconfigurable architectures. The detector achieves high data-level parallelism and near-ML performance by adopting a vector-architecture-friendly technique - parallel node perturbation. To further reduce the computational complexity, imbalanced node and successive partial node expansion schemes in con

[Context and Motivation] The main role of requirements engineering (RE) is to guide development projects towards implementing products that will appeal to customers. To effectively achieve this RE needs to be coordinated with and clearly communicated to the later software development activities. [Question/Problem] Communication gaps between RE and other development activities reduce coordination a

Due to changes in the development practices at Axis Communications, towards continuous integration, faster regression testing feedback is needed. The current automated regression test suite takes approximately seven hours to run which prevents developers from integrating code changes several times a day as preferred. Therefore we want to implement a highly selective yet accurate regression testing

This work explores the n-well/p-substrate photodiode in a deep submicron CMOS process. A CMOS chip is designed featuring different structures of the photodiode. When characterized at a wavelength of 850nm DC responsivities between 0.12 and 0.16 A/W and 3-dB bandwidths of about 6 MHz with a roll-off of about 5.5dB/decade are measured. These investigations are very useful in designing the transimped

Internet of Things (IoT) devices can be equipped with multiple heterogeneous network interfaces. An overwhelmingly large amount of services may demand some or all of these interfaces’ available resources. Herein, we present a precise mathematical formulation of assigning services to interfaces with heterogeneous resources in one or more rounds. For reasonable instance sizes, the presented formulat

The 60 GHz band is very promising for high data rate (>1 Gb/s) wireless systems operating at short ranges. However, due to the short wavelengths in this frequency band, the shadowing effects cuased by human bodies and furniture are severe and need to be modeled properly. In this paper, we present an experimental, measurement-based characterization of the reflection and shadowing effects in the 60

Context: Software product lines (SPL) are used in industry to achieve more efficient software development. However, the testing side of SPL is underdeveloped. Objective: This study aims at surveying existing research on SPL testing in order to identify useful approaches and needs for future research. Method: A systematic mapping study is launched to find as much literature as possible, and the 64

Flexgrid technology has recently been presented as the most promising option for upgrading the currently operating fixed grid optical networks and extending their capacity to be able to deal with the massive traffic volumes forecast for the next decade. Although the current traffic is successfully supported on fixed grid networks, flexgrid technology brings features that are not offered by the fix

The post-failure convergence of shortest path routing (SPR) protocols used in IP networks can be too slow to meet the restrictive requirements (i.e. maximum allowable delay, jitter, etc.) of the multimedia services and therefore new protection/restoration mechanisms combined with IP routing are of interest. The article addresses the optimization of three potential rerouting mechanisms based on the

In this paper we establish a geometry-based stochastic ultra-wideband channel model for outdoor infostations scenarios. We statistically describe the location and strength of clusters of scatterers, as well as the shape and width of visibility and shadowing regions. We also separately model diffuse radiation (which cannot be explained by the scatterer components), and show that its fading statisti

Large software organizations with a product line development approach face many challenges regarding testing. Test managers need to make tradeoffs along three dimensions of repeated testing (abstraction level, time and product space) and consider a range of goals and constraints. In order to keep pace with the decreased development time for new products, which is enabled by the systematic reuse, s

In this article we prove NP-hardness of two well-known optimization problems related to the design of multicommodity flow networks with two different methods for providing network resiliency against failures: path diversity and flow restoration. Path diversity is a static mechanism that consists of using, for each demand, a number of paths and oversizing the flows assigned to these paths so that f

The presented study deals with a specific rerouting strategy for protecting traffic flows in communication networks called Flow Adjustment Routing. The strategy is designed to handle partial link failures. We present two variants of the strategy and analyze their pros and cons. We show that the initial strategy is not directly implementable to cope with severe link failures such as total link fail

This paper presents results for vehicle-to-vehicle channel characterization based on measurements conducted for the merging lane scenarios on a highway. We present power delay profiles as well as channel gains and analyze important propagation mechanisms to see the impact of line-of-sight (LOS) and the antenna radiation pattern on the total received power. It is found that the absence of LOS and s

In software product line engineering, testing for regression concerns not only versions, as in one-off product development, but also regression across variants. We propose a 3D process model, with the dimensions of level, version and variant, to help analyze, plan and manage software product line testing. We derive the model from empirical observations of regression testing practice and software p