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Abstract in UndeterminedThis paper presents an inductorless ultra-low power radio receiver front-end intended for applications such as sensor networks and medical implants. It consists of low noise amplifier, quadrature mixer, and a frequency divider for the generation of quadrature local oscillator signals. The power consumption is just 282μW from a 0.9V supply when it operates in the 915 MHz ISM

This paper presents an energy efficient adaptive QR decomposition scheme for Long Term Evolution Advance (LTE-A) downlink system. The proposed scheme provides a performance robustness to fluctuating wireless channels while maintaining lower workload on a reconfigurable hardware. A statistic based algorithm-switching strategy is employed in the scheme to achieve workload reduction and stable comput

We study the notion of structured realizability for linear systems dened over graphs. A stabilizable and detectable realization is structured if the state-space matrices inherit the sparsity pattern of the adjacency matrix of the associated graph. In this paper, we demonstrate that not every structured transfer matrix has a structured realization and we reveal the practical meaning of this fact. W

Three mm-wave pulse generation circuits fabricated in a standard 65nm CMOS process are presented. Two versions are based on the cross-coupled NMOS LC-VCO (500um × 300 um), and one is based on the Colpitts VCO (600um × 300 um). No additional buffers are used in the cross-coupled versions, as they are directly loaded by 50 Ohms through a balun. They can produce measured pulses exceeding 8dBm peak ou

Parallel robots are generally said to be more accurate and have a smaller workspace compared to serial robots. With the Gantry-Tau robot, a parallel robot with relatively large workspace was presented. This article examines the end-effector positioning accuracy of the Gantry-Tau robot. End-effector positioning errors arising from joint positioning or modeling errors are studied. A geometric approa

A general framework for the study of robust synchronisation in large-scale networks is provided. Agents are represented as a common nominal linear time-invariant (LTI) single-input-single-output (SISO) system with simple poles on the imaginary axis, subject to LTI SISO stable multiplicative perturbations. The agents exchange information in order to achieve output-synchronisation, namely steer thei

Context: Duplicate detection is a fundamental part of issue management. Systems able to predict whether a new defect report will be closed as a duplicate, may decrease costs by limiting rework and collecting related pieces of information. Goal: Our work explores using Apache Lucene for large-scale duplicate detection based on textual content. Also, we evaluate the previous claim that results are i

Age of Information (AoI) is a relatively new metric introduced to capture the freshness of a particular piece of information. While throughput and delay measurements are widely studied in the context of dense IEEE 802.11 Wireless LANs (WLANs) little is known in the literature about the AoI in this context. In this work we study the effects on the average AoI and its variance when a sensor node is

In this paper, we investigate the impact of power amplifier (PA) nonlinear distortion in pre-coded multi-user large antenna or massive MIMO downlink systems. First, detailed signal and system models are derived for the received signal at single-antenna user equipment (UE) under channel-aware linear precoding in the base-station combined with behavioral models for the individual PA units, covering

This paper presents a data-aided Carrier Frequency Offset (CFO) estimation algorithm targeting the Wideband OFDM systems. Utilizing 3 consecutive preambles and processing them at frequency domain, the algorithm is robust to both Frequency Independent (F-I) and Frequency Dependent (F-D) I/Q Mismatch (I/Q-M). To evaluate the effectiveness of the proposed CFO estimation technique, we conduct extensiv

An M-BCJR algorithm is proposed and tested over an AWGN channel with moderate to very intense intersymbol interference (ISI). Two M-BCJR applications are evaluated, simple detection over the ISI channel and turbo equalization. The signaling is binary faster than Nyquist linear modulation. The ISI models tested correspond to transmission of increasingly many bits/Hz-s with a fixed signal spectra; t

The paper is devoted to modeling and optimization of reliable wireless mesh networks that employ directional antennas. We introduce two mixed-integer programming formulations that allow to simultaneously characterize routing patterns and transmission schedules. The first model allows for maximizing the minimal flow in a network. The second model involves reliability constraints and aims at minimiz