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This paper presents a directional analysis of the on-body propagation channels using the high resolution space alternating generalized expectation (SAGE) maximization algorithm. The analysis has been done on data obtained through FDTD simulations, on a male and a female numerical phantom. For estimating the angle of arrival (AoA) at a four element square array located at the chest, two different p

Wireless communication using very-large multiple-input multiple-output (MIMO) antennas is a new research field, where base stations are equipped with a very large number of antennas as compared to previously considered systems. Unlike the conventional small and compact antenna arrays, the very-large arrays may span many wavelengths in space, thus they can experience large-scale fading over the arr

Abstract in UndeterminedIn this paper, the orthogonality of dual-polarized MIMO channels with Rician fading is investigated in a measured urban macrocellular scenario. Overall, efficient two-stream MIMO communication can be achieved as more than 70% of the measured route achieves better channel orthogonality than the average performance of the reference IID Rayleigh channel. Furthermore, the study

Reliance on data for software systems engineering is increasing, e.g., to train machine learning applications. We foresee increasing costs for data collection and maintenance, leading to the risk of development budgets eaten up by commodity features, thus leaving little resources for differentiation and innovation. We therefore propose Open Collaborative Data (OCD) - a concept analogous to Open S

We present a general purpose algorithm for finding low-weight codewords as well as for decoding a received codeword in any quasi-cyclic code whose length and dimension is a multiple of a power of 2. In this paper, we apply the algorithm on a McEliece variant recently proposed by Misoczki et al. (MDPC-McEliece: New McEliece variants from moderate density parity-check codes, 2013). In their paper, t

Many companies and developers from OSS communities create open tools collaboratively in which software developers improve upon the code and share the changes within the community. Open tools (e.g., Jenkins, Gerrit, and Git) offer features or performance benefits that surpass their commercial counterparts in the core product development. Participation in OSS tools communities greatly dismantled the

Software bugs cost time, money, and lives. They drive software research and development efforts, and are central to modern software engineering. Yet we lack a clear and general definition of what bugs are. Some bugs are defects, clearly defined as failures to meet some requirement or specification. However,there are many forms of undesirable program behaviour that are completely compatible with a

This paper presents a fully integrated 60 GHz frontend for phased array receivers. For the first time in the literature a phase controlled phased locked loop (PC-PLL) is used for beamforming at 60 GHz. The front-end performs a two stage frequency down-conversion, first from 60 GHz to 20 GHz, then from 20 GHz to quadrature baseband. Both the local oscillator signals at 20 GHz and 40 GHz are generat

A variable gain transimpedance amplifier (TIA) is presented featuring single-ended to differential conversion by means of negative feedback. The proposed topology also ensures stability when amplifier gain is varied. Furthermore, effective input capacitance of the TIA is reduced by using a positive capacitive feedback. The circuit is intended for intermediate frequency (IF) over fiber systems, but

Reducing the complexity of decoding algorithms for LDPC codes is an important prerequisite for their practical implementation. In this work we propose a reduction of computational complexity targeting the highly reliable codeword bits and show that this approach can be seamlessly merged with the forced convergence scheme. We also show how the minimum achievable complexity of the resulting scheme f

Two branches of gated ring oscillators (GRO) act as the delay lines in 2-dimension Vernier time-to-digital converter (TDC). The proposed architecture reduces dramatically the inherent latency of vernier structure. The already small quantization noise of the standard Vernier TDC is further first-order shaped by the GRO operation. The TDC has been simulated in 90nm CMOS technology. Operating from 50

This paper presents a robust and low-complexity non-linearity suppression scheme for radio frequency (RF) transceiver building blocks to efficiently mitigate intermodulation distortion. The scheme consists of tunable RF components assisted by an auxiliary path equipped with an adaptive digital signal processing algorithm to provide the tuning control. This proposed concept of digitally-assisted tu

BACKGROUND: Direct-to-consumer telemedicine is an increasingly used modality to access primary care. Previous research on assessment using synchronous virtual visits showed mixed results regarding antibiotic prescription rates, and research on assessment using asynchronous chat-based eVisits is lacking.OBJECTIVE: The goal of the research was to investigate if eVisit management of sore throat, othe

In this paper, we combine practically verified results from circuit theory with communication-theoretic laws. As a result, we obtain closed-form theoretical expressions linking fundamental system design and environment parameters with the power consumption of analog front ends (AFEs) for communication receivers. This collection of scaling laws and bounds is meant to serve as a theoretical referenc

Importance: Prenatal diagnosis of complex congenital heart defects reduces mortality and morbidity in affected infants. However, fetal echocardiography can be limited by poor acoustic windows, and there is a need for improved diagnostic methods.Objective: To assess the clinical utility of fetal cardiovascular magnetic resonance imaging in cases in which fetal echocardiography could not visualize a