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This paper presents a continuous-time ΔΣ ADC in a 28nm-FDSOI CMOS technology. The ADC is clocked at 5GHz with a signal bandwidth of 250 MHz, for an oversampling ratio (OSR) of only 10. The conversion from high-level model to circuit-level implementation requires multiple high-speed design methodologies and a careful layout. A 4th order loop filter is adopted to enhance quantization noise shaping i
In this paper, we study event-based PID control from an optimal stochastic control perspective. The purpose is to better understand what implementation features are critical for achieving good event-based PID performance. For this end, we formulate an LQG control design problem for a double integrator process with an integral disturbance, where the solution is an ideal PID controller. We then cons
Signals are physical variables or quantities measured at various parts of a system, which when processed yield the desired information. A wide variety of signals are often encountered in describing many practical systems. Electrical signal, in form of current and voltage, is the most easily measured quantity, hence the need to use sensors and transducers to transform other non-electrical quantity
The ac frequency in electrical power systems is conventionally regulated by synchronous machines. The gradual replacement of these machines by asynchronous renewable-based generation, which provides little or no frequency control, increases system uncertainty and the risk of instability. This imposes hard limits on the proportion of renewables that can be integrated into the system. In this paper,
Biogenic volatile organic compounds (BVOCs) play essential roles in tropospheric chemistry, on both regional and global scales. The emissions of large quantities of species-specific BVOC depend not only on environmental (temperature, T; photosynthetically active radiation, PAR), but also physiological parameters (i.e. net photosynthetic rate, Pn; transpiration rate, Tr; stomatal conductance, gs an
Control systems can be vulnerable to security threats where an attacker gathers information about the execution of the system. In particular, side-channel attacks exploit the predictability of real-time control systems and of their schedules. To counteract their action, a scheduler can randomize the temporal execution of tasks and limit the amount of information the attacker can gather. Schedule r
Control theory has contributed a set of foundational techniques to handle "change" at runtime in software applications. These techniques however have fundamental limitations as well: (i) they require the development and understanding of mathematical models; (ii) synthesizing solutions is often done on a per-problem basis, discouraging flexibility and generality. Software engineering, as a discipli
Devices sharing a network compete for bandwidth, being able to transmit only a limited amount of data. This is for example the case with a network of cameras, that should record and transmit video streams to a monitor node for video surveillance. Adaptive cameras can reduce the quality of their video, thereby increasing the frame compression, to limit network congestion. In this paper, we exploit
A wideband 65-nm CMOS power amplifier (PA) is presented, with a decade frequency range from 600 MHz to 6.0 GHz. In this frequency range, the output power exceeds 26.6 dBm and the power gain and power-added efficiency (PAE) exceed 18.1 dB and 49%, respectively. For a 7.5-dB peak-to-average-power-ratio (PAPR) long term evolution (LTE) signal at 1.9 GHz, the circuit provides an average output power o
A continuous-time, 65-nm CMOS, front-end for processing DNA sequencing measurements from biological nanopore sensors is presented. The measured design has an input referred noise floor of 8.5\;{\text{fA}}/\sqrt {{\text{Hz}}} for 100 pA DC current while consuming 10X less power. The chip also consists of an integrated ADC.
As the Arctic warms, vegetation is responding, and satellite measures indicate widespread greening at high latitudes. This ‘greening of the Arctic’ is among the world’s most important large-scale ecological responses to global climate change. However, a consensus is emerging that the underlying causes and future dynamics of so-called Arctic greening and browning trends are more complex, variable a
The interest for studying server systems subject to cloned requests has recently increased. In this paper we present a model that allows us to equivalently represent a system of servers with cloned requests, as a single server. The model is very general, and we show that no assumptions on either inter-arrival or service time distributions are required, allowing for, e.g., both heterogeneity and d
Interesting approaches to counteract performance variability within cloud datacenters include sending multiple request clones, either immediately or after a specified waiting time. In this paper we present a performance model of cloud applications that utilize the latter concept, known as speculative execution. We study the popular Join-Shortest-Queue load-balancing strategy under the processor sh
Observations during the Ice in Clouds Experiment-Tropical (ICE-T) field experiment show that the ice particles concentration in a developing deep convective clouds at the level of T = −15 °C reached about 500 L−1, that is, many orders higher than that of ice-nucleating particle. To simulate microphysics of these clouds, the 2-D Hebrew University Cloud model (HUCM) with spectral bin microphysics wa
Event-based sampling has been proposed as a general technique for lowering the average communication rate, energy consumption and computational burden in remote state estimation. However, the design of the event trigger is critical for good performance. In this paper, we study the combination of innovation-based triggering and state estimation of nonlinear dynamical systems using the particle filt
We present a method for solving the general mixed constrained convex quadratic programming problem using an active set method on the dual problem. The approach is similar to existing active set methods, but we present a new way of solving the linear systems arising in the algorithm. There are two main contributions; we present a new way of factorizing the linear systems, and show how iterative ref
The VIVE lighthouse system is evaluated for indoor positioning of micro unmanned aerialcvehicles (MUAVs). A detailed mathematical analysis is provided, including a Cramer-Raocbound derivation and performance analysis of the MUAV state estimate. The lighthousecmeasurements are fused with inertial measurements in a multiplicative extended Kalmanfilter (MEKF). We consider two implementations, one w
We address access control of reconfigurable scan networks, like IEEE Std. 1687 networks. We propose an on- chip test block to perform: (1) test for faulty scan-chains, (2) localization of faulty scan-chains and (3) repair by excluding faulty scan-chains, and an access control block to (1) control so scan- chains (instruments) are only accessed in allowed combinations, (2) detection of access attem
H-infinity optimal control and estimation are addressed for a class of systems governed by partial differential equations with bounded input and output operators. Diffusion equations are an important example in this class. Explicit formulas for the optimal state feedback controller as well as the optimal state estimator are given. Unlike traditional methods for H-infinity synthesis, no iteration i
Particle methods such as the particle filter and particle smoothers have proven very useful for solving challenging nonlinear estimation problems in a wide variety of fields during the last decade. However, there are still very few existing tools available to support and assist researchers and engineers in applying the vast number of methods in this field to their own problems. This paper identifi
