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Many modern software applications have performance requirements, like mobile and embedded systems that must keep up with sensor data, or web services that must return results to users within an acceptable latency bound. For such applications, the goal is not to run as fast as possible, but to meet their performance requirements with minimal resource usage, the key resource in most systems being en

We consider a multiple-input multiple-output (MIMO) channel with inter-symbol interference (ISI) where signal detection is highly complex due to the large signal state-space dimensionality. A common strategy is to apply a front-end filter (FEF) to eliminate the ISI dimension (i.e. full ISI equalization). This FEF is then followed by a frequency non-selective MIMO detector. However, another, much l

Mathematical optimization is becoming increasingly important for engineering in general and control in particular. This thesis deals with numerical methods, primarily direct collocation, and symbolic methods, primarily block-triangular ordering and tearing, for numerical solution of general dynamic optimization problems involving dynamical systems modeled by large-scale differential-algebraic equa

This work presents a digital calibration technique in continuous-time (CT) delta-sigma (Δ Σ) analog to digital converter. The converter is clocked at 144 MHz with a low oversampling ratio (OSR) of only 8. Dynamic element matching is not efficient to linearize the digital to analog converter (DAC) when the OSR is very low. Therefore, non-idealities in the outermost multi-bit feedback DAC are measur

The trend in cellular chipset design today is to incorporate support for a larger number of frequency bands for each new chipset generation. If the chipset also supports receiver diversity two low noise amplifiers (LNAs) are required for each frequency band. This is however associated with an increase of off-chip components, i.e. matching components for the LNA inputs, as well as complex routing o

Decision making and requirements scoping occupy central roles in helping to develop products that are demanded by the customers and ensuring company strategies are accurately realized in product scope. Many companies experience continuous and frequent scope changes and fluctuations but struggle to measure the phenomena and correlate the measurement to the quality of the requirements process. We pr

We present the PalCom Object Notation, a textual data representation format for communication between internet of things which support binary and textual data. The format does not require parsing of user data (or the “payload”) and is thus efficient to use also for large binary values such as digital images, audio and video as well as for short textual values. These can be mixed in the same messag

This paper presents a link adaptive processor to perform low-complexity channel estimation and QR decomposition (QRD) in Long Term Evolution-Advanced (LTE-A) receivers. The processor utilizes frequency domain correlation of the propagation channel to adaptively avoid unnecessary computations in the received signal processing, achieving significant complexity reduction with negligible performance l

We propose a novel approach to the problem of inverse kinematics for possibly redundant planar manipulators. We show that, by considering the joints as point masses in a fictitious gravity field, and by adding proper constraints to take into account the length of the links, the kinematic inversion may be cast as a convex programming problem. Convex constraints in the decision variables (in particu

The problem of synthesizing network-decentralized observers arises when several agents, corresponding to the nodes of a network, exchange information about local measurements to asymptotically estimate their own state. The network topology is unknown to the nodes, which can rely on information about their neighboring nodes only. For homogeneous systems, composed of identical agents, we show that a

We address H-infinity state feedback and give a simple form for an optimal control law applicable to linear time invariant systems with symmetric and Hurwitz state matrix. More specifically, the control law as well as the minimal value of the norm can be expressed in the matrices of the system's state space representation, given separate cost on state and control input. Thus, the control law is tr

This paper considers switching output feedback control of linear systems and variable-structure systems. Theory for stability analysis and design for a class of observer-based feedback control systems is presented. A circle-criterion approach can be used to design an observer-based state feedback control which yields a closed-loop system with specified robustness characteristics. The approach is r

In this paper we show how to build an economically optimal feedback control strategy for the re-dispatch of electricity generation. We assume that the operator steers production in a set of controllable power plants by altering the active power set-point of each generator, within a set of predefined set-points. The operators strategy will be based on balancing the operating cost against the expect

Harmonic task scheduling has many attractive properties, including a utilization bound of 100% under rate-monotonic scheduling and reduced jitter. At the same time, it places a severe constraint on the task period assignment for any application. In this paper, we explore the use of harmonic task scheduling for applications with multiple feedback control tasks. We present an algorithm for finding h

This contribution reviews theory, algorithms, and validation results for system identification of continuous-time models from finite non-uniformly sampled input-output sequences. The algorithms developed are autoregressive methods, and methods of stochastic realization adapted to the continuous-time context. The resulting model can be decomposed into an input-output model and a stochastic innovati

Telecommunication monitoring data requires the automation of data analysis workflows. A data mining tool provides data workflow management systems to process and perform analysis tasks. This paper presents an evaluation of two example data mining tools following the principles of design of experiment (DOE) to run forecasting and clustering workflows for telecom monitoring data. We conduct both qua

Direct conversion receivers are widely used for full duplex mobile radio communication systems. This paper describes a novel SAW-less single-ended RF amplifier connected to a single-ended mixer with a feedback loop that suppresses the second-order distortion from TX cross modulation of the LO-leakage as well as DC-offset at the mixer output. In Monte Carlo simulations the design achieves +47 dBm m