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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
Box jellyfish have an impressive set of 24 eyes of four different types, including eyes structurally similar to those of vertebrates and cephalopods [1, 2]. However, the known visual responses are restricted to simple phototaxis, shadow responses, and object avoidance responses [3-8], and it has been a puzzle why they need such a complex set of eyes. Here we report that medusae of the box jellyfis
Bayesian optimization is a widely used method for optimizing expensive black-box functions, with Expected Improvement being one of the most commonly used acquisition functions. In contrast, information-theoretic acquisition functions aim to reduce uncertainty about the function’s optimum and are often considered fundamentally distinct from EI. In this work, we challenge this prevailing perspective
A closely-packed ultrawideband (UWB) multiple- input multiple-output (MIMO)/diversity antenna (of two elements) with a size of 25 mm by 40 mm is proposed for USB dongle applications. Wideband isolation can be achieved through the different patterns and polarizations of the two antenna elements. Moreover, the slot that is formed between the monopole and the ground plane of the half slot antenna is
Multi-antenna design in compact mobile handsets at frequency bands below 1 GHz is very challenging, since severe mutual coupling is commonly induced by simultaneous excitation of the chassis’ fundamental dipole mode by more than one antenna element. To address this problem, a novel multi-antenna design approach is proposed herein to obtain efficient and uncorrelated antennas. By manipulating the c
In this paper, we describe an end-to-end system that automatically extracts RDF triples describing entity relations and properties from unstructured text. This system is based on a pipeline of text processing modules that includes a semantic parser and a coreference solver. By using coreference chains, we group entity actions and properties described in different sentences and convert them into en
In this paper, we present a random puncturing analysis of low-density parity-check (LDPC) code ensembles. We derive a simple analytic expression for the iterative belief propagation (BP) decoding threshold of a randomly punctured LDPC code ensemble on the binary erasure channel (BEC) and show that, with respect to the BP threshold, the strength and suitability of an LDPC code ensemble for random p
Building big data analytics applications (BDA) in the Cloud introduces inevitable challenges such as loss of control and uncertainty. To address the existing challenges, numerous efforts have been made on BDA application engineering to optimise quality of BDA applications in the Cloud, such as performance and reliability. However, there is still a lack of systematic view on engineering BDA applica
It has been postulated that six co-located orthogonally polarized electrical and magnetic dipoles can offer up to six degrees of freedom (DOFs) in a multipath scattering environment. In other words, a six-fold increase in channel capacity can be achieved in the context of MIMO systems. However, due to the complexity in designing and measuring such a six-port antenna, to our knowledge, no experimen
This letter reports the capacity performance of a handheld dual-band dual-antenna compact MIMO terminal, which utilizes uncoupled adaptive impedance matching for capacity maximisation. The capacity is evaluated at 0.825 GHz and 2.35 GHz in an indoor office environment. The results show that adaptive matching enhances capacity by up to 44% and 22% at the low and high frequency bands, respectively,
Correlation coefficient, as a critical performance metric of multiple antenna systems, can be calculated from the 3D radiation patterns of the antennas for multipath environments with uniform 3D angular power spectrum. A simpler, faster and lower cost approach uses the antennas’ scattering parameters to determine correlation coefficient. However, the method assumes lossless antennas, and hence onl
The design of multiple antennas in compact mobile terminals is a significant challenge, due to both practical and fundamental design tradeoffs. In this paper, fundamental antenna design tradeoffs of multiple antenna terminals are presented in the framework of characteristic mode analysis. In particular, interactions between the antenna elements and the characteristic modes and their impact on desi
Seven aliphatic dicarboxylic acids (C3-C9) along with phthalic acid, pinic acid and pinonic acid were determined in 35 aerosol (PM10) samples collected over the year at Vavihill sampling station in south of Sweden. Mixture of dichloromethane and methanol (ratio 1:3) was preferred over water for extraction of samples and extraction was assisted by ultrasonic agitation. Analytes were derivatized usi
Despite its long history, the Theory of Characteristic Modes has only been utilized in antenna design for perfect electric conductors. This is due to computational problems associated with dielectrics and magnetic materials. In particular, the symmetric form of the PMCHWT surface formulation for the Method of Moments (MoM) solves for both external (real) and internal (non-real) resonances of a str
Compact arrays such as multiple antennas on a mobile terminal suffer from low efficiency and high correlation between antenna signals. In the present paper, a simple and rigorous procedure for decoupling two closely coupled antennas with a parasitic scatterer is proposed. The parasitic scatterer, which can be an additional antenna, acts as a shield between two active antenna elements. In contrast
We study the potential benefits of cooperative multiple-input multiple-output signaling from multiple coherent base stations with one or more mobile stations in an urban macrocellular environment at 2.66 GHz. The analysis uses fully-coherent measurements of the channel from three base stations to a single mobile station equipped with four antennas. The observed channels are used to explore the gai
