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In this paper, a compact pattern reconfigurable dual-antenna array is designed at 2.65 GHz for MIMO terminal applications, such as laptops. Each antenna is composed of two layers, i.e., the monopole layer and the PIFA layer. By switching the PIN diodes on each layer, its radiation patterns can be varied between conical and boresight patterns. Two such identical antennas are placed side by side on
Objective This study provides the summary of current knowledge about migrant work in agriculture available from journal articles, books, reports and other relevant academic publications, focusing on political, economic, legal, social and medical aspects of migrant work in agriculture. Methods A systematic search was carried out on the LibHub and Google Scholar databases in order to compile the e
Intense competition in rapidly changing markets puts intense pressure on product definition and the associated requirements engineering processes. An extensive literature review has identified that brand inertia, customer inertia, inappropriate market entry strategies and an inability to satisfy customer needs or expectations are the principle contributors to customer product rejection. While RE p
Coordinated Multi Point (CoMP) transmission and reception techniques are used in order to improve the performance of single or multiple cells in wireless systems. A system using CoMP techniques is capable of jointly optimizing its transmission and/or reception and, hence, achieving higher performance. In this work, performance evaluation of three CoMP techniques are performed based on simulations
The possibility of using radio over fiber (RoF) analog transmissions to characterize the wireless propagation channel of distributed antenna systems is investigated. In particular, the coherence time of kilometer-long, fiber-based networks is analyzed. Joint measurements of the phase noise of parallel links to the same site (intra-site) and to different sites (inter-site) in such a network are pre
A fully integrated remote antenna unit (RAU) intended for fiber-fed distributed multiple-input multiple-output systems is presented. The circuit is designed for narrowband (60 MHz) time-division duplex systems, where an IF over fiber approach is chosen to facilitate the use of low-cost optical components and integrated photodetectors. A novel antenna switch control scheme is introduced, which enab
Massive MIMO is a promising technology for the coming 5G wireless systems. In this paper, a programmable baseband processor specifically designed for uplink symbol detection targeting massive MIMO is presented with a novel matrix inversion method proposed to obtain more precise and efficient computation. Including a microcode controlled channel preprocessing unit and a pipelined detection unit, th
This paper serves as an overview to the special session Circuits and Systems for 5G on IEEE International Conference on ASIC (ASICON) 2015. More specifically, we introduce two of enabling technologies for the coming 5G wireless era, namely massive multiple-input multiple-output (MIMO) technique and advanced coding techniques such as polar codes. Massive MIMO is a relatively new wireless communicat
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
Open Source Software (OSS) created a paradigm shift within the software engineering field prompting further research to understand how mature, industry grade, software can be produced in an online milieu with distributed and lightly managed developers contributing source code in their free time. The OSS has become also a major revenue generator for many commercial organizations, and has found its
There has been extensive research about single link multiple-input multiple-output (MIMO) channels, both simulated and measured, but only a few studies have targeted multilink analysis with measured channel data. Hence, in this presented report, the authors analyse the influence of spatial separation of user terminals and the human shadowing effect on the MIMO capacity and on the signal-to-interfe
Non-Gaussian stochastic fields are introduced by means of integrals with respect to independently scattered stochastic measures distributed according to generalized Laplace laws. In particular, we discuss stationary second order random fields that, as opposed to their Gaussian counterpart, have a possibility of accounting for asymmetry and heavier tails. Additionally to this greater flexibility th
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
A method for determination of polycyclic aromatic hydrocarbons (PAHs) from aerosols was developed. Instead of conventionally used non-polar or slightly polar phenylmethylpolysiloxane column a highly polar, highly substituted, cyanopropyl column (VF-23 MS) was used for separation of PAHs. Based on hollow fiber micro-porous membrane liquid-liquid extraction (HF-MMLLE) a method was developed for samp
Three areas of ongoing research in channel coding are surveyed, and recent developments are presented in each area: spatially coupled Low-Density Parity-Check (LDPC) codes, non-binary LDPC codes, and polar coding.
