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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
We focus on improving resilience of cloud services (e.g., e-commerce website), when correlated or cascading failures lead to computing capacity shortage. We study how to extend the classical cloud service architecture composed of a load-balancer and replicas with a recently proposed self-adaptive paradigm called brownout. Such services are able to reduce their capacity requirements by degrading us
Spatially-Coupled LDPC (SC-LDPC) codes have been recently shown to be very efficient for transmissions over nonergodic channels, in particular over block-fading channels [1]. In fact, it is possible to design a SC-LDPC code with any given code diversity [2]. In this work, we investigate the performance of SC-LDPC codes over block-fading channels, assuming a mismatch (or offset) between the first b
We introduce a mixed-integer optimization model for two-layer IP-over-Flexgrid networks, and present a cost study performed using the CPLEX package for the introduced model. The study concerns a generic German network with 12 nodes and 20 links in the optical layer, and a set of six IP traffic matrices with increasing demand volumes. The optimization assumes a hot-standby mechanism in the optical
We present a model for estimating the final keep/cancel decision point, on a per-feature basis, for scope inclusion in a future release. The Basic Lost Opportunity Estimation Model (BLOEM), based on data from a company that uses an agile-inspired software development model, supports feature selection when the time-dependent business value estimates change as the requirements analysis progresses. T
Measurement results of an analog channel decoder in 65 nm CMOS are presented. We target ultra compact and low power applications with low to medium throughput requirements. The decoding core is designed for (7,5)(8) convolutional codes and takes 0.104 mm(2) on silicon. The degrading effects of analog imperfections are investigated and the presented results allow power, performance and throughput t
Industry--academia collaboration is critical for empirical research to exist. However, there are many obstacles in the collaboration process. This paper reports on the experiences gained by the author, in a 2-year collaboration project on software testing which involved on-site work by the researcher in the industry premises. Based on notes, minutes of meetings, and progress reports, the project h
Reference attribute grammars (RAGs) is a powerful formalism for developing modular extensible compilers and program analysis tools. This paper presents JavaRAG, an implementation of RAGs as a Java library that is independent of the abstract syntax tree structure. This makes it possible to extend legacy compilers implemented in Java with RAG computations. We have evaluated the approach by integrati
This paper proposes a process independent post layout de-synchronization flow implemented in tool command language working on designs operating in the sub-V-T regime. The overhead due to the self-timed operation is combated by introducing full-custom delay elements and latches for a standard 65-nm CMOS process. The flow offers the possibility to adjust granularity based on user requirements. Case
Consider the communication model (y) over bar = H F (x) over bar + (n) over bar, where H; F are real-valued matrices, (x) over bar is a data vector drawn from some real-valued lattice (e.g. M-PAM), (n) over bar is additive white Gaussian noise and (y) over bar is the received vector. It is assumed that the transmitter and the receiver have perfect knowledge of the channel matrix H (perfect CSI) an
Shadowing from other vehicles can degrade the performance of vehicle-to-vehicle communication systems significantly. It is thus important to characterize and model the influence of common shadowing objects like trucks in a proper way. However, the scenario of a truck as an obstacle in highly dynamic rural and highway environments is not yet well understood. In this paper we analyze the distance de
We consider demand response solutions having the capability to monitor different variables at users' premises, like presence and temperature, and to control individual appliances. We focus on the optimal control of the appliances during time periods where the available capacity is not enough to satisfy the demand generated by houses operating freely. We propose an approach to define the utility of
