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This paper presents a multimode soft-output multiple-input multiple-output (MIMO) signal detector that is efficient in hardware cost and energy consumption. The detector is capable of dealing with spatial-multiplexing (SM),break space-division-multiple-access (SDMA), and spatial-diversity (SD) signals of 4 ✕ 4 antenna and 64-QAM modulation. Implementation-friendly algorithms, which reuse most of t
In this work a low power 5th order chebyshev active-RC low pass filter that meets Rel-8 LTE receiver requirements has been designed with programmable bandwidth and overshoot. Designed for a homodyne LTE receiver, filter bandwidths from 700kHz to 10MHz are supported. The bandwidth of the operational amplifiers is improved using a novel phase enhancement technique. The filter was implemented in 65nm
Abstract in Undeterminedhis survey deals with computational complexity of column generation problems arising in the design of survivable communication networks. Such problems are often modeled as linear programs based on noncompact multicommodity flow network formulations. These formulations involve an exponential number of path-flow variables, and therefore require column generation to be solved
In this work we present a fully integrated Radio-Fiber interface implemented in 65nm CMOS, intended for remote antenna units (RAUs) in distributed antenna systems. To relax the requirements on the optical components, an intermediate frequency (IF) signal (100MHz) is transmitted over the multi-mode fiber, which is then up-converted to 2.2GHz inside the RAU. Local Oscillator (LO) signals to the mixe
In this paper a number of low-complexity channel estimator structures tailored to the needs of LTE terminals have been investigated. The focus has been on the algorithms exhibiting reduced complexity while providing an acceptable level of performance. To design these estimators other factors such as interoperability with another OFDM-based standard, DVB-H, in a multi-standard environment have been
A general coupling-based model framework for wideband multiple-input multiple-output (MIMO) channels is presented in this paper. Under this framework, the channel state information (CSI) tensor can be expressed by the product of a coupling tensor, a complex Gaussian tensor and three unitary matrices. The unitary matrices can be either eigenbases or steering matrices in different domains. The coupl
In this paper, we present a novel approach for the design of rate-maximizing channel shortening detectors with soft feedback side information for frequency-selective channels. The detector is a soft-input soft-output detector and constitutes one of the components of an iterative receiver. The design optimization is performed from an information-theoretic perspective where we maximize the achievabl
Radio links in wireless mesh networks (WMN) can select one of several modulation and coding schemes (MCS). A MCS assignment influences links data rates and their mutual interference, and therefore should be optimized. We consider joint optimization of link rate assignment and transmission scheduling in order to maximize the minimal flow in a WMN. One of the main difficulties stems from the require
Abstract in UndeterminedThe properties of the single-link multiple-input-multiple- output (MIMO) propagation channels have been analyzed in many studies based on extensive propagation measurements. In this letter, we extend the measurement-based analysis to dual-link MIMO propagation channels. Here, we examine interlink correlation by evaluating the correlation of eigenvectors obtained from multip
Proximity of user has been established as a major cause of performance degradation in multiple-input multiple-output (MIMO) terminals. Here, we investigate the potential of adaptive impedance matching (AIM) to improve the performance of two MIMO terminals in a free space (FS) and a two-hand (TH) user scenario, assuming uniform 3D angular power spectrum for the incoming signal. The results show tha
In this paper an implementation of a reduced complexity matching pursuit channel estimator for LTE is presented. The design contains an FFT/IFFT module with non-radix 2 units and the core estimator. The FFT/IFFT module is flexible enough to perform both operations using the same hardware. Based on prior work the needed internal word lengths are found. Internal shifts are employed to maximize the u
In this article, we revisit a classical optimization problem occurring in designing survivable multicommodity flow networks. The problem, referred to as FR, assumes flow restoration that takes advantage of the so-called stub release. As no compact linear programming (LP) formulation of FR is known and at the same time all known noncompact LP formulations of FR exhibit NP-hard dual separation, the
In many organisations a gap exists between IT management and emergency managemement. This paper illustrates how process improvement based on a maturity model can be used to help organisations to evaluate and improve the way they include IT dependability information in their emergency management. This paper presents the IDEM3 (IT Dependability in Emergency Management Maturity Model) process improve
A receiver front-end supporting contiguous and non-contiguous intra-band carrier aggregation scenarios with a fully integrated spectrum sensor that can detect both in-gap and out-of-band blockers has been implemented in 65nm CMOS technology. An NF of 2.5dB is achieved using a noise canceling LNTA, and linearized OTAs are used to achieve an IIP3 improvement of up to 6.5dB in-band and 11dB at the fi
The nature of scientific research and the development of scientific software have similarities with processes that follow the agile manifesto: responsiveness to change and collaboration are of the utmost importance. But how well do current scientific software development processes match the practices found in agile development methods, and what are the effects of using agile practices in such proc
This paper is a survey of how linear attacks can be applied on stream ciphers. It gives an overview of the development of linear attacks and a short theoretical explanation on how a linear attack on a stream cipher is typically launched today. The main part of the paper is then a more detailed description of the application of linear attacks on three stream cipher designs, namely Grain, Pomaranch,
With the introduction of standards such as DSRC and WAVE, vehicular ad hoc networks (VANET) are being considered as candidates to improve road safety. Safety applications developed on top of VANET enable vehicle and driver improved awareness of the road situation through vehicles sharing their status and knowledge of the road conditions. In order for these systems to operate, they depend on reliab
