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This paper presents the design and implementation of an analog-to-information converter (AIC) capable of Nyquist and compressed sensing modes of operation. The core of the AIC is a 10-bit edge-triggered charge-sharing SAR ADC with a figure of merit (FOM) of 55 fJ/conversion-step and Nyquist-sampling rate of 9.5 Msample/s. The integration of a pseudorandom clock generator enables compressed sensing operation via random sampling and subsequent asynchronous successive approximation conversion by the core ADC. The AIC allows complete reconstruction of a spectrum consisting of sparse single tones or sparse frequency bands using compressed sensing algorithms based on \ell{{1}}-minimization as well as \ell{{1,2}} regularization, which exploits group sparsity. Implemented in 90 nm CMOS, the prototype SAR ADC core achieves a maximum sample rate of 9.5 MS/s, an ENOB of 9.3 bits, and consumes 550 \muW from a 1.2 V supply. Measurement results of the AIC demonstrate an effective bandwidth of 25 MHz, which is 5\times greater than Nyquist-sampling rate with an improved effective FOM of 12.2 fJ/conversion-step for signals with sparse frequency support. [ABSTRACT FROM PUBLISHER]

This paper presents a wide range, voltage controlled-current source circuit that is optimized to compensate for both process and temperature variations. Compensation for process variations is realized by cancellation of the threshold voltage variations. Temperature compensation is applied by the use of a poly resistor. Ninety samples from 3 different chips of the same wafer run were measured, and for the nominal value of 25 nA, current sources have a standard deviation of 1.22% (4.8\times improvement over an uncompensated current reference). The simulated standard deviation is 8%, resulting a simulated improvement factor of 8\times, when samples from different wafer runs are to be measured. Measured temperature drift is 250 ppm/^\circC for a temperature range of 0–80 ^\circC. For the mentioned performance, the circuit consists of only 7 components occupying an area of 64 \mum\times\,91 \mum, using AMS 0.35 \mum, 5 V CMOS process technology. The new current source is used to mimic the behavior of an infrared detector, which creates current in the range of 1–50 nA. A modified version of proposed current source is also designed with no off-chip bias voltages, and has a temperature coefficient of 57 ppm/^\circC for 9 nA with an acceptable process compensation. [ABSTRACT FROM PUBLISHER]

Diagnosability is an important property that determines at the design stage how accurate any diagnosis algorithm can be on a partially observable system and thus has significant economic impact on the improvement of performance and reliability of complex systems. Very recently distributed approaches for diagnosability began to be investigated since centralized approaches are not realistic for large systems due to the combinatorial explosion of the search space. In this paper, we propose a new optimized algorithm for pattern diagnosability analysis of distributed systems with modular structure, where we obtain the original pattern diagnosability information from the relative components before abstracting the sufficient and necessary information to be propagated to other connected components. Then, the diagnosability decision can be made after global consistency checking at the proper level of the subsystem involved. Our experimental results and complexity analysis illustrate the correctness and efficiency of our approach both in a practical and theoretical way. Finally, we distinguish our work by presenting related works before the conclusion. [ABSTRACT FROM AUTHOR]

In this paper, an ultra-compact model for nanometer CMOS transistors, suitable for the analysis of digital circuits, is proposed. Starting from modified and more accurate versions of classical compact models, an extremely simple one (nine parameters and piecewise linear versus relationships in both triode and saturation) is extracted. All the main physical effects that are predominant in nanometer technologies are included and the model is shown to allow an accurate and quick estimation of parameters such as delay or dc transfer curves. Simulation results are extracted in a 65-nm CMOS technology. [ABSTRACT FROM AUTHOR]

Adaptive noise cancellation (ANC) techniques that extract a desired signal from background noise have many applications in different engineering disciplines. In ANC, the corrupted signal is passed through a filter that tends to suppress the noise while leaving the original signal unchanged. This paper demonstrates that the adaptive noise cancellation technique can be embedded in the digital signal postprocessing of a sigma-delta analog-to-digital converter and effectively reduces the quantization noise as well as the thermal noise at the output of the converter. The combination of ANC and the noise-shaping technique enable high-resolution analog-to-digital conversion in wideband applications where noise shaping alone cannot provide enough suppression of quantization noise due to the low oversampling ratio. [ABSTRACT FROM AUTHOR]

In this paper, a new type of control, called a receding horizon finite memory control (RIIFMC) or a model predictive finite memory control, is proposed as an optimal output feedback control for stochastic state-space systems. Constraints such as linearity, finite memory structure, and unbiasedness from the optimal state feedback control are required in advance, and in addition, the performance criterion of quadratic cost is required. Constraints for the input and the state are not assumed in this paper. The RHFMC is obtained directly by minimizing the performance criterion for stochastic state-space systems with the previous constraints. It is shown that the RHFMC can be separated into a receding horizon control and a finite-impulse response filter. The stability of the RHIFMC is investigated. The validity of the proposed RHFMC is illustrated by a numerical example. [ABSTRACT FROM AUTHOR]

Cellular nonlinear/neural network (CNN) has been recognized as a powerful massively parallel architecture capable of solving complex engineering problems by performing trillions of analog operations per second. The memristor was theoretically predicted in the late seventies, but it garnered nascent research interest due to the recent much-acclaimed discovery of nanocrossbar memories by engineers at the Hewlett-Packard Laboratory. The memristor is expected to be co-integrated with nanoscale CMOS technology to revolutionize conventional von Neumann as well as neuromorphic computing. In this paper, a compact CNN model based on memristors is presented along with its performance analysis and applications. In the new CNN design, the memristor bridge circuit acts as the synaptic circuit element and substitutes the complex multiplication circuit used in traditional CNN architectures. In addition, the negative differential resistance and nonlinear current–voltage characteristics of the memristor have been leveraged to replace the linear resistor in conventional CNNs. The proposed CNN design has several merits, for example, high density, nonvolatility, and programmability of synaptic weights. The proposed memristor-based CNN design operations for implementing several image processing functions are illustrated through simulation and contrasted with conventional CNNs. Monte-Carlo simulation has been used to demonstrate the behavior of the proposed CNN due to the variations in memristor synaptic weights. [ABSTRACT FROM AUTHOR]

Several policies have recently been proposed for attaining the maximum throughput region, or a guaranteed fraction thereof, through dynamic link scheduling. Among these policies, the ones that attain the maximum throughput region require a computation time which is linear in the network size, and the ones that require constant or logarithmic computation time attain only certain fractions of the maximum throughput region. In contrast, in this paper we propose policies that can attain any desirable fraction of the maximum throughput region using a computation time that is largely independent of the network size. First, using a combination of graph partitioning techniques and Lyapunov arguments, we propose a simple policy for tree topologies under the primary interference model that requires each link to exchange only 1 bit information with its adjacent links and approximates the maximum throughput region using a computation time that depends only on the maximum degree of nodes and the approximation factor. Then we develop a framework for attaining arbitrary close approximations for the maximum throughput region in arbitrary networks, and use this framework to obtain any desired tradeoff between throughput guarantees and computation times for a large class of networks and interference models. Specifically, given any ϵ > 0, the maximum throughput region can be approximated in these networks within a factor of 1 - ϵ using a computation time that depends only on the maximum node degree and ϵ. [ABSTRACT FROM AUTHOR]

In this paper, we study the control of an ellipsoid immersed in an infinite volume of ideal fluid. The dynamics of the uncontrolled body are given by Kirchhoff's laws. The control system is underactuated: one control is an acceleration along an axis of the ellipsoid and two are angular accelerations around the other two axes. By adopting a backstepping viewpoint, we prove that the position and the attitude of the solid can be forced to approximately follow any given path, using fast-oscillating controls. Moreover, we prove that the controlled mechanical system (which includes the impulses) is completely controllable in an arbitrary small time. [ABSTRACT FROM AUTHOR]

This paper addresses the problem of cooperative control of a team of distributed agents with decoupled nonlinear discrete-time dynamics, which operate in a common environment and exchange-delayed information between them. Each agent is assumed to evolve in discrete-time, based on locally computed control laws, which are computed by exchanging delayed state information with a subset of neighboring agents. The cooperative control problem is formulated in a receding-horizon framework, where the control laws depend on the local state variables (feedback action) and on delayed information gathered from cooperating neighboring agents (feedforward action). A rigorous stability analysis exploiting the input-to-state stability properties of the receding-horizon local control laws is carried out. The stability of the team of agents is then proved by utilizing small-gain theorem results. [ABSTRACT FROM AUTHOR]

This paper studies rate requirements for state estimation in linear time-invariant (LTI) systems where the controller and the plant are connected via a noiseless channel with limited capacity. Using information theoretic arguments, we obtain first for scalar systems, and subsequently for multidimensional systems, lower bounds on the data rates required for state estimation under three different stability criteria, namely monotonic boundedness of entropy, asymptotic stability of distortion, and support size stability. Further, the minimum data rate achievable by any source-encoder is computed under each of these criteria, and the best rate achievable with quantization is shown to be in agreement with the information-theoretic bounds in some specific cases (such as if the system coefficient is an integer or if the criterion is an asymptotic one). Existence of optimal variable-length and fixed-length quantizers are studied and optimal quantizers are constructed under each of these criteria. One observation is that, the uniform quantizer is, in addition to being simple, efficient in linear control systems. [ABSTRACT FROM AUTHOR]

Most of the results on decentralized supervisory control are based on supervisors that make unconditional decisions: "enable" and "disable." In this paper, we introduce and study the properties of decentralized supervisory control architectures where supervisors are allowed to make conditional decisions in addition to unconditional decisions, The conditional decisions we consider are of the form: "enable if nobody disables" and "disable If nobody enables:' We characterize the notion of conditional coobservability that appears in the necessary and sufficient conditions for the existence of supervisors in the context of such control architectures. This condition relaxes the previous notions of coobservability for unconditional architectures. The key properties of conditional coobservability are studied. We develop a polynomial-time algorithm for verifying the notion of conditional coobservability. A polynomial-lime method of partitioning the controllable events between "enable by default" and "disable by default" is presented. [ABSTRACT FROM AUTHOR]

Focuses on the decline in industrial researches in electrical engineering in the U.S. as of September 2003. Reasons for the decline in industry papers; State of the research system during the dot-com boom; Examination of papers included in the 2003 IEEE International Communications Conference by the author.

A novel technique is proposed to generate robust, low distortion sine waves. In this method, outputs of a phase shift oscillator (PSO) are weighted and summed to obtain multiple outputs with very low distortion and precise phase relationship. The method allows a programmable number of harmonic distortion components to be cancelled over a wide frequency range. This work derives the condition for the weights on the outputs of the PSO to be a real quantity, and demonstrates how this can be used to generate low distortion sine waves. With the proposed method, in an N-stage PSO, harmonics up to N-2th can be canceled. Simulation results using commercial operational amplifier spice models are presented to demonstrate low distortion sine wave generation over 2 kHz–180 kHz frequency range. The method has been experimentally verified using extremely low-cost, discrete components to produce 100 dB total harmonic distortion (THD) sine wave. [ABSTRACT FROM PUBLISHER]

A 6-GHz phase-locked loop based spread-spectrum clock generator employing a self-oscillating technique is proposed. The clock generator adopts the property of the inherent oscillation of a charge-pump PLL while introducing no extra quantization noise. With the amplitude and frequency control, modulation frequency and frequency deviation can be tuned at 31.5 kHz and 5000 ppm, respectively. The measured EMI reduction is 12.5 dB at the 100-kHz resolution bandwidth. The measured root mean square jitter is 2 ps and peak-to-peak is 15 ps. This work was fabricated in a 90-nm digital CMOS technology, occupies 0.54 mm^2 and consumes 14.4 mW from a 1.2-V supply. [ABSTRACT FROM PUBLISHER]

Two low-noise bidirectional current acquisition circuits for interfacing with electrochemical amperometric biosensor arrays are presented. The first design is a switched-capacitor transimpedance amplifier (TIA). The second design is a current conveyer (CC) with regulated-cascode current mirrors. Both circuits employ chopper stabilization to reduce flicker noise. The TIA and the CC were prototyped in 0.13 \mum CMOS and consume 3 \muW and 4 \muW from a 1.2 V supply, respectively. The electrical and electrochemical recording properties of both circuits have been characterized. The current conveyer exhibits superior performance in low-concentration electrochemical catalytic reporter sensing, as less switching noise is injected into the biosensor. [ABSTRACT FROM PUBLISHER]

Memristors-based resistive logic computation units are introduced. By controlling the memristors' conditional set operation adaptively to one of the input polarities, bipolar signal multiplication of an input and a stored reference bit is performed by unipolar memristor devices and control switches. The multiplication result is registered in an output nonvolatile memristor so that the computed output can be accessed anytime later on by reading the output memristor's state. A memristive multiplier circuit demonstrates a fast and highly sensitive pattern recognition for highly complex inputs. [ABSTRACT FROM PUBLISHER]

Metastability is the inability of a latched comparator to reach a decision in the available amount of time. Existing analyses of metastability disregard noise, treating it as a deterministic phenomenon that inevitably happens every-time the input voltage, vIdiff, falls in a certain interval around 0, and which is restricted to the aforementioned interval. Also, according to the conventional analysis, the decision takes an infinite amount of time if vIdiff=0. This work analyzes metastability in the presence of noise, showing it is actually a random phenomenon whose probability of occurrence is derived. It is concluded that there is no input value for which metastability inevitably occurs (not even vIdiff=0), and that there may be a significant probability of metastability at input voltage values much larger than those predicted by conventional analysis. All the theoretical results are in agreement with extensive HSPICE transient noise simulations. [ABSTRACT FROM PUBLISHER]

Discrete-time two-valued processes are of paramount importance in Information Engineering and their analysis is usually addressed assuming they have at most the memory of one step in the past. Since this is a quite limiting assumption, a general analytic formula is given here for the spectrum of stochastic antipodal processes with finite memory m ⩾ 1. The formula is derived within a generalized Markov framework and depends on the eigenstructure of a suitably defined transition matrix that is also exploited to give ergodicity conditions. The complexity of the overall analysis depends on the size of such matrix which is exponential in m. Within that framework a slightly less general but more tractable scheme for the generation of antipodal processes with prescribed spectral profile is introduced leveraging on a linear probability feedback. For such a scheme, whose complexity is linear in m, an alternative spectrum formula is derived as well as a synthesis procedure going from spectrum specification to feedback filter design. Both the general case and the linear probability feedback scheme are exemplified in some special cases. [ABSTRACT FROM AUTHOR]

A recently reported result concerning the designing adaptive impulsive observer for nonlinear continuous-time systems using LMI-based approach is revisited. It is shown that a key condition of the result can not be satisfied. [ABSTRACT FROM PUBLISHER]