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Due to the increasing number of infotainment and safety functions in vehicles, the need for reliable communication link is becoming very critical. A key consideration in providing a reliable link is the antenna performance, which is conventionally evaluated by its efficiency and ability to provide the required coverage upon integration in vehicles. However, modern vehicles are equipped with many e

A microstrip antenna integration with a power amplifier is presented for the 60 GHz band. The antenna is a single layer 4×4 square patches array. The power amplifier is injection locked, designed in a 65 nm CMOS technology, with single-ended input and output signals. The integration is realized by means of bond wire connections. The antenna and the power amplifier are fabricated, characterized and

In the paper we address an important problem in minimum cost design of Elastic Optical Networks (EON), namely the problem of optimizing the configurations of Sliceable-Bandwidth Variable Transceivers (S-BVT) at the EON nodes. We first show how this optimization problem can be viewed and modeled as a combination of three bin-packing subproblems, with additional constraints ensuring feasibility of t

We present an optimization procedure that mixes advanced large-scale optimization methods and heuristics to solve large instances (with over 1.7 million integer variables) of the routing and spectrum allocation (RSA) problem - a basic optimization problem in flexgrid elastic optical networks. We formulate the problem as a mixed-integer program for which we develop a branch-and-price algorithm enha

The symmetric PMCHWT method of moments (MoM) impedance matrix allows for the characteristic modes (CMs) of a structure containing dielectric to be found. Recently, this impedance matrix was proven to provide non-real solutions which can be attributed to the MoM internal resonance problem. These internal resonances can be removed through different CM post-processing techniques. However, these studi

This work presents a broadband SiGe Power Amplifier (PA) for operation between 60-90 GHz covering both 71-76 GHz and 81-86 GHz E-Band sub-bands. It consists of a two-stage differential cascode amplifier using an LC-interstage matching network in the interface between the stages. Single-ended to differential conversion is accomplished by the use of two stacked 1-To-1 transformers, achieving a simul

In the paper we introduce an optimization framework for traffic restoration in optical wireless networks. As such networks experience multiple partial link failures, we introduce a generic extension of restoration strategies developed for wired networks (that assume total link failures) which enables handling partial link failures as well. The particular traffic restoration strategy studied in the

TO-DCF, a new backoff scheme for 802.11, has the potential to significantly increase throughput in dense wireless LANs while also opportunistically favouring nodes with heavier traffic loads and/or better channel conditions. In this paper we present an analytical model to investigate the behaviour and performance of the TO-DCF protocol with regards to operating parameters such as the number of nod

We present a high performance low-power digital base-band architecture, specially designed for an energy optimized duty-cycled wake-up receiver scheme. Based on a careful wake-up beacon design, a structured wake-up beacon detection technique leads to an architecture that compensates for the implementation loss of a low-power wake-up receiver front-end at low energy and area costs. Design parameter

This paper presents an adaptive QR decomposition (QRD) processor for five-band carrier aggregated LTE-Adownlinks. The design uses time and frequency correlationproperties of wireless channels to reduce QRD computationswhile maintaining an uncoded bit error rate loss below 1 dB.An analysis on the performance of a linear interpolating QRD ispresented and optimum distances for different channel condi

Requirements Engineering has recently been greatly influenced by the way how firms use Open Source Software (OSS) and Software Ecosystems (SECOs) as a part of their product development and business models. This is further emphasized by the paradigm of Open Innovation, which highlights how firms should strive to use both internal and external resources to advance their internal innovation and techn

This paper presents preliminary results for a novel 128-antenna massive Multiple-Input, Multiple-Output (MIMO) testbed developed through Bristol Is Open in collaboration with National Instruments and Lund University. We believe that the results presented here validate the adoption of massive MIMO as a key enabling technology for 5G and pave the way for further pragmatic research by the massive MIM

Adult hematopoietic stem cells (HSCs) reside in bone marrow and are maintained in a dormant state within a special microenvironment, their so-called "niche". Detaching from the niche induces cell cycle progression, resulting in a reduction of the reconstitution capacity of HSCs. In contrast, fetal liver HSCs actively divide without losing their stem cell potentials. Thus, it has been unclear what

In wireless channel measurements, the relatively weak cross-polarized multipath components (MPCs) are typically severely affected by the measurement noise level. As shown in this letter, the typical cross-polarization ratio (XPR) model parameter estimation, which ignores the existence of censored samples, may lead to significant errors. We demonstrate how to achieve accurate parameter estimates wi

This issue's letter discusses the proper use of sampling in software engineering research surveys.

The proper alignment of requirements engineering and testing (RET) can be key to software's success. Three practices can provide effective RET alignment: using test cases as requirements, harvesting trace links, and reducing distances between requirements engineers and testers. The Web extra https://youtu.be/M65ZKxfxqME is an audio podcast of author Elizabeth Bjarnason reading the the Requirements

We consider channel shortening (CS) algorithms for communication systems where multiple single antenna nodes are transmitting single carrier signals to a single antenna receiver over known intersymbol interference channels. We discuss seven methods to shorten the intersymbol interference (ISI) channels, and the parameters are optimized from a generalized mutual information (GMI) perspective. The m

It is known that the compactness of mobile terminals complicates the design of multiple antennas, since coupling between the antennas increases when they are placed in proximity of one another. While it is possible to mitigate coupling between closely spaced antennas, a tradeoff in bandwidth is required. In this paper, we highlight ground plane excitation as an additional dimension to consider in