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An increasing demand of higher data rates in wireless communication forces the industry to look to higher frequencies to find the required bandwidths. This thesis is about analog transmitters in CMOS for millimeter-wave communication, and it focuses on improving power amplifiers and frequency generation circuits, and increase their efficiency. This thesis starts with an introduction to millimeter-

Context: Open tools (e.g., Jenkins, Gerrit and Git) offer a lucrative alternative to commercial tools. Many companies and developers from OSS communities make a collaborative effort to improve the tools. Prior to this study, we developed an empirically based theory for companies’ strategic choices on the development of these tools, based on empirical observations in the telecom domain. Aim: The ai

We compared three different Graphical User Interfaces (GUI) that we have designed and implemented to enable human supervision of an unmanned ship. Our findings indicate that a 3D GUI presented either on a screen or in a Virtual Reality (VR) setting provides several objective and subjective benefits compared to a Baseline GUI representing traditional tools.

Version 3 av ecoinvent är den första databasen att erbjuda möjligheten att koppla samman livscykelinventeringar (LCI) utefter olika länkningsalgoritmer. Genom dessa länkningsalgoritmer tar ecoinvent nu fram bakgrundslivscykelinventeringar med både medeldata och långsiktig marginaldata (t.ex. över elmarknader i olika länder). Idealt sett representerar långsiktig marginaldata över elmarknader den ytVersion 3 of the ecoinvent database is the first background database to offer the possibility to link life cycle inventories (LCI) according to different linking algorithms. Using those algorithms, ecoinvent now provides both average and long-term, marginal background LCI data, (e.g. for electricity markets for different countries). Long-term, marginal data for electricity markets ideally represen

Background: Data quickly emerges as a core driver of businesses across the worlddue to rapidly expanding use in different areas, such as Machine Learning. In orderfor the data-related organizational operations to be efficient, the topic of data shar-ing has to be explored. This thesis focuses on understanding inter-organizationaldata sharing by exploring practices and challenges that are present w

Cemented carbides with tungsten carbide grains as hard phase and metallic cobalt binder phase are used extensively for drill bit inserts for rock drilling. The process of rock drilling is severe with some of the wear happening through fracture in the cemented carbide. This work investigated two cemented carbides with iron rich alternative binder phases containing different amounts of FCC phase, in

Indoor sensing is challenging because of the multi-bounce effect, spherical wavefront, and spatial nonstationarity (SNS) of the near-field effect. This paper addresses radio-based environment sensing considering these issues. Specifically, graph theory (GT) is used to model the multi-bounce propagation of the near field. In this manner, indoor reflectors/scatterers are modeled as vertices in a pro

We propose and analyze a novel scheme based on LDPC codes for quantitative group testing. The key underlying idea is to augment the bipartite graph by introducing hidden non-binary variables to strengthen the message-passing decoder. This is achieved by grouping items into bundles of size q within the test matrix, while keeping the testing procedure unaffected. The decoder, inspired by some works

Clog is a declarative language for describing static code checkers for C. Clog is a dialect of Datalog and adds syntactic pattern matching over the C language. We have built Clog using the MetaDL framework and the Clang C compiler frontend. The MetaDL framework supports Datalog evaluation and syntactic patterns, while the Clang frontend provides AST facts and an AST matching mechanism.We provide t

This study presents a measurement campaign with an ultra-large-scale antenna array in both Line-of-Sight (LoS) and Non-Line-of-Sight (NLoS) outdoor scenarios. Measurements were conducted at a center frequency of 15 GHz with a bandwidth of 4 GHz. A virtual 40×40 planar antenna array, formed by moving a vertically-polarized bi-conical omni-directional antenna (ODA) along regularly spaced grids, was

Isoprene is a reactive hydrocarbon emitted to the atmosphere in large quantities by terrestrial vegetation. Annual total isoprene emissions exceed 300 Tg a−1, but emission rates vary widely among plant species and are sensitive to meteorological and environmental conditions including temperature, sunlight, and soil moisture. Due to its high reactivity, isoprene has a large impact on air quality an

The number of users and the information transmitted over wireless networks have been growing constantly during the last decades. Nowadays, the pace of this growth is extremely sharp because of the new applications which heavily rely on wireless networks to meet users' demands. Wireless networks infrastructures are constantly developing to meet these demands. Massive multiple-input multiple-output

This letter proposes a novel, low-cost, single-layer filtering antenna (filtenna) for wireless communications. The design consists of a compact circular substrate-integrated waveguide (SIW) cavity, a centrally offset metal post for feeding, and a slot radiator for efficient radiation. It is based on an SIW coaxial line and utilizes multiple TM and quasi-TM modes. Unlike filtennas that rely on inli

In this work we investigate the development of functionally graded cemented carbides, featuring macro gradients on the millimeter scale, where Fe, or Ni is the binder phase. Two composites, WC-Ni and WC-Fe with 20 % binder by volume were produced by addition of TiC on the surface of the samples before sintering at 1475 °C for 1 h. The sintered samples were analyzed using electron microscopy and mi

Dual-band shared-aperture Fabry-Pérot cavity (DS-FPC) antennas with single-layer partially reflective surface (PRS) are inherently limited in the achievable frequency ratio. This paper analyzes such antennas to derive the feasible range of frequency ratio and thereafter proposes a dual-band shared-aperture antenna that can fill the frequency ratio gap. The novel design integrates a short backfire

The forest floor acts as a source of terpenoid emissions to the atmosphere. These emissions can further impact atmospheric particle formation and impact the atmospheric radiation balance. Climate change escalates wildfire frequency in boreal forests. Wildfires are major disturbances with long-term ecosystem impacts, particularly on the forest floor, significantly influencing terpenoid sources and

Autonomous robots must operate reliably and safely under uncertain, dynamic conditions over extended periods. To ensure such operational robustness, it is vital that both developers and operators can clearly and verifiably specify functional requirements and safety constraints throughout the robot software lifecycle. My research targets different layers of robot operational safety: early error det