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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

Feedback control has been applied to computing systems, usually taking a designed system and closing a loop to adjust some of its parameters. However, the design of computing systems components as controllers have shown advantages with respect to state-of-the-art techniques, especially in the scheduling domain, where uniprocessor schedulers have been designed as discrete-time control structures. H

A divider-less all digital phase locked loop (ADPLL) with a high frequency resolution is implemented. All blocks excluding digitally controlled oscillator (DCO) and time to digital converter (TDC) are realized in standard digital design which consumes less power. The DCO core adopts an improved source-varactor LC resonant tank to achieve a 20KHz frequency resolution. With the help of an additional

A 24 GHz 2-path beamforming receiver front-end in 90 nm CMOS is presented. It consists of two direct conversion front-ends followed by a baseband block performing phase rotation and signal combination. The baseband phase rotation is performed by combining the quadrature phases using digitally controlled weights, achieving a phase resolution of 11 degrees. From each of the two inputs the front-end

An extended Kalman-Yakubovich-Popov (KYP) Lemma for positive systems is derived. The main difference compared to earlier versions is that non-strict inequalities are treated. Matrix assumptions are also less restrictive. Moreover, a new equivalence is introduced in terms of linear programming rather than semi-definite programming. As a complement to the KYP lemma, it is also proved that a symmetri

As farms are getting bigger with more animals, less manual supervision and attention can be given the animals on both group and individual level. In order not to jeopardize animal welfare, automated supervision is in some way already in use. Function and control of ventilation is already in use in modern pig stables, e.g. by the use of sensors for temperature, relative humidity and malfunction con

In this paper a distributed version of the Kalman filter is proposed. In particular, the estimation problem is reduced to the optimization of a cost function that depends on the system dynamics and the latest output measurements and state estimates which is distributed among the agents by means of dual decomposition. The techniques presented in the paper are applied to estimate the position of mob

We consider a class of distributed algorithms for computing arithmetic averages (average consensus) over net- works of agents connected through digital noisy broadcast channels. Our algorithms combine error-correcting codes with the classical linear consensus iterative algorithm, and do not require the agents to have knowledge of the global network structure. We improve the performance by introduc

Analytical Multiple-Input Multiple-Output (MIMO) models are often attractive due to their low complexity when analyzing possibilities and limitations in the system. In this paper we outline a a possible dual link extension of an analytical MIMO channel model and investigate its suitability based on measurements of a dual link MIMO scenario. The extension is based on the correlation matrix distance

In secure computing systems, isolation between different components is normally the basis for security. However, ab- solute isolation is seldom desired nor practical. Often for the system to function, a secure communication channel between otherwise isolated components is also needed. In this work, we consider implementation of the secure Remote Procedure Call (RPC) mechanism defined by the Global

Issue management in market-driven software projects is constantly under time pressure. A limited set of developers must share their time between developing features for the next release and resolving reported issues. Project managers need to find the appropriate balance between a high quality product and fast time to market. We study a telecom company in Sweden developing embedded systems for a co

Massive multiple-input multiple-output (MIMO) is one of the main candidates to be included in the fifth generation (5G) cellular systems. For further system development it is desirable to have real-time testbeds showing possibilities and limitations of the technology. In this paper we describe the Lund University Massive MIMO testbed – LuMaMi. It is a flexible testbed where the base station operat