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The growing complexity of industrial robot work-cells calls for the use of advanced orchestration techniques to promote flexibility and reusability. This paper presents a solution based on service-oriented platforms that endorses the separation of concerns, coordination and execution. The execution is kept inside each individual device and their functionality is exposed via automatic generation of

Abstract in UndeterminedAn efficient technique is introduced to reduce mutual coupling between two closely spaced PIFAs for MIMO mobile terminals. The proposed mutual coupling reduction method is based on a T-shape slot impedance transformer and can be applied to both single-band and dual-band PIFAs. For the proposed single-band dual PIFAs, the 10 dB impedance bandwidth covers the 2.4 GHz WLAN ban

Multi-antenna enabled terminal devices are required to comply with the standards for limiting human exposure to electric fields. However, when compared to traditional single-antenna terminals, a comprehensive evaluation of specific absorption rate (SAR) for multi-antenna terminals is impractical. This is because both the power allocation and phase of the electric fields from different antennas are

In this paper, we study the performance of precoding schemes for cooperative transmission of multiple coherent base stations (BSs) that allow for overlapped clustering in a measured urban macrocellular environment at 2.66 GHz, in order to verify previous findings obtained by using simulated channel data. The evaluated precoding schemes include zero-forcing (ZF), layered virtual signal-to-interfere

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

Conventional antennas in single-antenna terminals that resonate at frequencies lower than 1 GHz usually rely on the chassis as the main radiator. To effectively exploit chassis excitation for MIMO terminals, each of the multiple antennas is required to excite one distinct chassis mode. However, in today's terminals, there is typically only one chassis mode that can radiate efficiently at frequenci

From our experimental investigation of multiple-antenna performance and user impact of a realistic mobile terminal setup, we find that apart from the important loss of efficiency due to the user hand, the impact on the individual antennna elements and the directional impact of the user body shadowing have quite small influence on the diversity and capacity performance. It is found that the top and

A simple and intuitive metric of multiplexing efficiency is proposed for evaluating the performance of MIMO antennas in the spatial multiplexing mode of operation. Apart from gaining valuable insights into the impact of antenna efficiency, efficiency imbalance and correlation on multiplexing performance, the metric is particularly useful for antenna engineers whose goal is to achieve the optimum a

We consider the problem of approximating functions that arise in wave-equation imaging by sums of wave packets. Our objective is to find sparse decompositions of image functions, over a finite range of scales. We also address the naturally connected task of numerically approximating the wavefront set. We present an approximation where we use the dyadic parabolic decomposition, but the approach is

Characteristic mode analysis provides unparalleled insights into designing high performance multiple-input multiple-output (MIMO) terminal antennas at frequencies where the antenna elements are constrained to be electrically small. Conventionally, an electrically small single-antenna utilizes the fundamental characteristic mode of the terminal chassis to obtain sufficient bandwidth while maintaini

In urban environments, airborne particles are continuously emitted, followed by atmospheric aging. Also, particles emitted elsewhere, transported by winds, contribute to the urban aerosol. We studied the effective density (mass-mobility relationship) and mixing state with respect to the density of particles in central Copenhagen, in wintertime. The results are related to particle origin, morpholog

Capacity improvement of intrasite cooperative MIMO using all three 120 degree-sectors of a base station (BS) site is studied for the first time in a measured urban environment at 2.65GHz. The results show that the mean uplink capacity gain exceeds 40% in as much as 1/4 of the coverage area, relative to the best single-sector link with no cooperation. In addition, a simple simulation model is devel

Multiplexing efficiency has recently been proposed as a performance metric for characterizing the absolute efficiency of MIMO antennas in a reference channel. In this work, we generalize this metric to account for arbitrary propagation channels, so the impact of the channel can also be studied. Using the extended definition of multiplexing efficiency, the respective roles of effective antenna gain

As a cost-effective option for Cloud consumers, spot service has been considered to be a significant supplement for building a full-fledged market economy for the Cloud ecosystem. However, unlike the static and straightforward way of trading on-demand and reserved Cloud services, the market-driven regulations of employing spot service could be too complicated for Cloud consumers to comprehensively

Evaluating SAR for multi-antennas is difficult and impractical due to the arbitrary power allocation and phase of the electric fields from different antennas causing the total field to change randomly. In this context, a simplified approach was recently proposed for assessing SAR when more than one antenna is transmitting simultaneously. The metric of time averaged simultaneous peak SAR (TASPS) wa

Abstract in UndeterminedOperational semantics and attribute grammars are examples of formalisms that can be used for generating compilers. We are interested in finding similarities and differences in how these approaches are applied to complex languages, and for generating compilers of such maturity that they have users in industry.As a specific case, we present a comparative analysis of two compi