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Combining attribute grammars with object-oriented programming supports a new kind of declarative programming, allowing compilers to be built in a highly extensible manner. By leveraging a base compiler, extended languages can be supported at a relatively low cost. Recent work shows the applicability of the technique to general-purpose programming languages like Java. In this article, we illustrate
Correlation coefficient of received signals across a pair of antennas is a key performance indicator for multiple-input multiple-output (MIMO) systems. For multipath environments with uniform 3D angular power spectrum, the signal correlation between two antennas can be exactly calculated from their 3D radiation patterns. When radiation patterns are unavailable, a simplified approach that only requ
Using the metric of channel capacity, three dual-antenna multiple-input multiple-output (MIMO) terminals with adaptive impedance matching were evaluated at LTE Band 13 in four different user scenarios using simulation. Each of the three terminals is equipped with a slot-monopole antenna and a planar inverted-F antenna (PIFA). The slot monopole is fixed at one edge of the chassis, whereas the locat
Model-based systems in control are a means to utilize efficiently human knowledge and achieve high performance. While models consisting of formalized knowledge are used during the engineering step, running systems usually do not contain a high-level, symbolic representation of the control and most of its properties, typically named numerical parameters. On a system level and beyond the plant data,
Abstract in UndeterminedMultiple-antenna handheld terminals are an integral part of the latest mobile communication systems, due to the adoption of multiple-input multiple-output (MIMO) technology. In this contribution, MIMO performances of three multiple-antenna configurations for smart phones are investigated in an urban macrocellular environment, based on an extensive MIMO measurement campaign
Truncated correlation and convolution operators is a general operator-class containing popular operators such as Toeplitz (Wiener-Hopf), Hankel and finite interval convolution operators as well as small and big Hankel operators in several variables. We completely characterize the symbols for which such operators have finite rank, and develop methods for determining the rank in concrete cases. Such
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
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
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
An increasing demand from e.g. real-time multimedia applications (IPTV, OTT) adds strains on especially DSL based access links. In this paper we argue why it is important to study DSL link impairments and their impact on QoS parameters on higher layers. We discuss the need for establishing methods for quality of service estimation with cross layer techniques and present some initial results.
Pattern reconfigurability is a desirable feature of mobile handset antennas, as it enables the antennas to adapt to non-stationary propagation environments. However, it is difficult to vary the radiation pattern of a handset antenna at frequencies below 1 GHz because the entire chassis commonly acts as the main radiator. Hence, designing pattern reconfigurability based on the antenna element (seco
We present a comparative exploratory analysis of two proximity networks of mobile phone users, the Proximates network and the Reality Mining network. Data for both networks were collected from mobile phones carried by two groups of users. Periodic Bluetooth scans were performed to detect the proximity of other mobile phones. The Reality Mining project took place in 2004-2005 at MIT, while Proximat
The performance of broadband microwave 40 W and 55 W LDMOS integrated power amplifiers is reported. A 30 V LDMOS process with 500 nm gate length was used for the design. Single and dual die packages were evaluated. A dual die package provides flexibility in output power and efficiency depending on combiner topology at the input and output of the circuit. Different saturated power and efficiency ar
To make autonomous, affordable ships feasible in the real world, they must be capable of safely navigating without fully relying on GPS, high-resolution 3D maps, or high-performance navigation sensors. We suggest a method for estimating the position using affordable navigation sensors (compass and speed log or inertial navigation sensor), sensors used for perception of the environment (cameras, ec
Recent advances in autonomous vehicles present new opportunities in Intelligent transportation systems (ITS) to address urban transport challenges. Therefore, urban traffic scenarios, and in particular intersections as a bottleneck of transportation network, has received significant attention. In this paper we investigate intelligent traffic control mechanisms for autonomous vehicles at intersecti
