# IEEE Transactions on Circuits and Systems I: Regular Papers

## Filter Results

Displaying Results 1 - 25 of 30

Publication Year: 2007, Page(s):C1 - C4
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• ### IEEE Transactions on Circuits and Systems&mdash;I: Regular Papers publication information

Publication Year: 2007, Page(s): C2
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• ### A Comprehensive Analysis of Quadrature Signal Synthesis in Cross-Coupled RF VCOs

Publication Year: 2007, Page(s):689 - 704
Cited by:  Papers (34)
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This paper presents a linear model for cross-coupled quadrature voltage-controlled oscillators (QVCOs) together with a simple generalized proof for the condition of quadrature oscillation. The analysis provides insight into the oscillation mechanism and the previously observed frequency shift when the magnitude and phase of the coupling signal are deliberately modified by a complex coupling coeffi... View full abstract»

• ### New Compact CMOS Li-Ion Battery Charger Using Charge-Pump Technique for Portable Applications

Publication Year: 2007, Page(s):705 - 712
Cited by:  Papers (64)
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This paper presents a new compact CMOS Li-Ion battery charger for portable applications that uses a charge-pump technique. The proposed charger features a small chip size and a simple circuit structure. Additionally, it provides basic functions with voltage/current detection, end-of-charge detection, and charging speed control. The charger operates in dual-mode and is supported in the trickle/larg... View full abstract»

• ### A Wide Tuning Range$G_{m}$–$C$Continuous-Time Analog Filter

Publication Year: 2007, Page(s):713 - 722
Cited by:  Papers (21)
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A CMOS operational transconductance amplifier (OTA) for low-power and wide tuning range filter application is proposed in this paper. The OTA can work from the weak inversion region to the strong inversion region to maximize the transconductance tuning range. The transconductance can be tuned by changing its bias current. A fifth-order Elliptic low-pass filter implemented with the OTAs was integra... View full abstract»

• ### Bandpass Sigma&ndash;Delta Modulator Employing SAW Resonator as Loop Filter

Publication Year: 2007, Page(s):723 - 735
Cited by:  Papers (12)  |  Patents (1)
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Continuous-time bandpass (BP) sigma-delta modulators (SigmaDeltaMs) employing surface acoustic wave (SAW) resonators as loop filters are presented. Compared with the loop filters realized with G<sub>m</sub>-C and LC resonators, the SAW resonator has the advantage of high-Q factor, wide resonant frequency range and accurate resonant frequency without the need for automatic tuning. With ... View full abstract»

• ### Design of a CMOS Potentiostat Circuit for Electrochemical Detector Arrays

Publication Year: 2007, Page(s):736 - 744
Cited by:  Papers (63)  |  Patents (4)
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High-throughput electrode arrays are required for advancing devices for testing the effect of drugs on cellular function. In this paper, we present design criteria for a potentiostat circuit that is capable of measuring transient amperometric oxidation currents at the surface of an electrode with submillisecond time resolution and picoampere current resolution. The potentiostat is a regulated casc... View full abstract»

• ### An Accurate Automatic Quality-Factor Tuning Scheme for Second-Order <emphasis emphasistype="italic">LC</emphasis> Filters

Publication Year: 2007, Page(s):745 - 756
Cited by:  Papers (3)  |  Patents (2)
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This paper presents a scheme to accurately tune the quality factor of second-order LC bandpass filters. The information of the magnitude response at the center and one of the cutoff frequencies is used to tune both the amplitude and the quality factor of the filter using two independent yet interacting loops. Furthermore, the synergic interaction between the loops makes the proposed scheme stable ... View full abstract»

• ### Efficient Multibit Quantization in Continuous-Time$\Sigma \Delta$Modulators

Publication Year: 2007, Page(s):757 - 767
Cited by:  Papers (23)
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A drawback of continuous-time SigmaDelta modulators is their sensitivity to clock jitter. One way to counteract this is to use a multibit feedback loop which requires a (high resolution) multibit quantizer. However, every extra bit in the quantizer doubles its complexity, power consumption and capacitive load for the analog circuit that needs to drive the quantizer. In this paper a new concept for... View full abstract»

• ### Sensitivity Characteristics of Inverse Class-E Power Amplifier

Publication Year: 2007, Page(s):768 - 778
Cited by:  Papers (25)
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In this paper, an analysis is performed in order to determine the effects that variations in circuit component values, frequency, and duty cycle have on the performance of the newly introduced inverse Class-E amplifier. Analysis of the inverse Class-E amplifier under the generalized condition of arbitrary duty cycle is performed and it is shown that the inverse Class-E amplifier is reasonably tole... View full abstract»

• ### LSB Dithering in MASH Delta–Sigma D/A Converters

Publication Year: 2007, Page(s):779 - 790
Cited by:  Papers (54)  |  Patents (1)
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Theoretical sufficient conditions are presented that ensure that the quantization noise from every constituent digital delta-sigma (DeltaSigma) modulator in a multistage digital DeltaSigma modulator is asymptotically white and uncorrelated with the input. The conditions also determine if spectral shape can be imparted to the dither's contribution to the power spectral density of the multistage dig... View full abstract»

• ### Low-Cost Fast VLSI Algorithm for Discrete Fourier Transform

Publication Year: 2007, Page(s):791 - 806
Cited by:  Papers (16)
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A primeN-length discrete Fourier transform (DFT) can be reformulated into a (N-1)-length complex cyclic convolution and then implemented by systolic array or distributed arithmetic. In this paper, a recently proposed hardware efficient fast cyclic convolution algorithm is combined with the symmetry properties of DFT to get a new hardware efficient fast algorithm for small-length DFT, and then WFTA... View full abstract»

• ### Design of an FFT/IFFT Processor for MIMO OFDM Systems

Publication Year: 2007, Page(s):807 - 815
Cited by:  Papers (73)
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In this paper, we present a novel 128/64 point fast Fourier transform (FFT)/ inverse FFT (IFFT) processor for the applications in a multiple-input multiple-output orthogonal frequency-division multiplexing based IEEE 802.11n wireless local area network baseband processor. The unfolding mixed-radix multipath delay feedback FFT architecture is proposed to efficiently deal with multiple data sequence... View full abstract»

• ### A Class of Maximum-Period Nonlinear Congruential Generators Derived From the R&eacute;nyi Chaotic Map

Publication Year: 2007, Page(s):816 - 828
Cited by:  Papers (52)  |  Patents (1)
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In this paper, a family of nonlinear congruential generators (NLCGs) based on the digitized Reacutenyi map is considered for the definition of hardware-efficient pseudorandom number generators (PRNGs), and a theoretical framework for their study is presented. The authors investigate how the nonlinear structure of these systems eliminates some of the statistical regularities spoiling the randomness... View full abstract»

• ### A State-Space Approach to Intermodulation Distortion Estimation in Fully Balanced Bandpass$G_{m}$–$C$Filters With Weak Nonlinearities

Publication Year: 2007, Page(s):829 - 844
Cited by:  Papers (8)
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A state-space approach to estimating intermodulation distortion in bandpass Gm-C filters with fully balanced, weakly nonlinear transconductors is introduced. It results in compact analytic expressions applicable to Gm-C filters of any order. For verifying the theory, two Gm-C filters with fully balanced weakly nonlinear transconductors have been designed using Cade... View full abstract»

• ### Wordlength Optimization of Linear Time-Invariant Systems With Multiple Outputs Using Geometric Programming

Publication Year: 2007, Page(s):845 - 854
Cited by:  Papers (6)
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This paper proposes two new methods for optimizing hardware resources in finite wordlength implementation of multiple-output (MO) linear time-invariant (LTI) systems. The hardware complexity is measured by the exact internal wordlength used for each intermediate data. The first method relaxes the wordlength from integer to real-value and formulates the design problem as a geometric programming, fr... View full abstract»

• ### Formal Synthesis of Circuits With Minimum Noise Figure Using Linear Matrix Inequalities

Publication Year: 2007, Page(s):855 - 862
Cited by:  Papers (4)
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We present an algorithm that determines whether an n-port with given impedance matrix at a set of frequencies can be realised from ideal transformers and multiple instances of a set of linear, time-invariant components (specified by their admittance parameters). The algorithm is based on solving a linear matrix inequality derived using Tellegen's theorem. If the n-port can be realised, the noise f... View full abstract»

• ### Blind Calibration of Timing Offsets for Four-Channel Time-Interleaved ADCs

Publication Year: 2007, Page(s):863 - 876
Cited by:  Papers (85)  |  Patents (9)
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In this paper, we describe a blind calibration method for timing mismatches in a four-channel time-interleaved analog-to-digital converter (ADC). The proposed method requires that the input signal should be slightly oversampled. This ensures that there exists a frequency band around the zero frequency where the Fourier transforms of the four ADC subchannels contain only three alias components, ins... View full abstract»

• ### Least-Squares and Minimax Design of Polynomial Impulse Response FIR Filters for Reconstruction of Two-Periodic Nonuniformly Sampled Signals

Publication Year: 2007, Page(s):877 - 888
Cited by:  Papers (27)
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This paper proposes polynomial impulse response finite-impulse response filters for reconstruction of two-periodic nonuniformly sampled signals. The foremost advantages of using these reconstruction filters are that on-line filter design thereby is avoided and subfilters with fixed dedicated multipliers can be employed in an implementation. The overall implementation cost can in this way be reduce... View full abstract»

• ### Balanced Binary-Tree Decomposition for Area-Efficient Pipelined FFT Processing

Publication Year: 2007, Page(s):889 - 900
Cited by:  Papers (44)
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This paper presents an area-efficient algorithm for the pipelined processing of fast Fourier transform (FFT). The proposed algorithm is to decompose a discrete Fourier transform (DFT) into two balanced sub-DFTs in order to minimize the total number of twiddle factors to be stored into tables. The radix in the proposed decomposition is adaptively changed according to the remaining transform length ... View full abstract»

• ### Blind Identification of MIMO Channels Using Optimal Periodic Precoding

Publication Year: 2007, Page(s):901 - 911
Cited by:  Papers (21)
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We propose a method for blind identification of multiple-input mutiple-out (MIMO) finite-impulse response (FIR) channels that exploits cyclostationarity of the received data induced at the transmitters by periodic precoding. It is shown that, by properly choosing the precoding sequence, the MIMO FIR transfer functions, with M<sub>t</sub> inputs and M<sub>r</sub> outputs, ca... View full abstract»

• ### On Stability of Neural Networks by a Lyapunov Functional-Based Approach

Publication Year: 2007, Page(s):912 - 924
Cited by:  Papers (16)
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In this paper, a new Lyapunov functional-based method is proposed for the stability analysis of delayed cellular neural networks (DCNN). Global exponential stability conditions are obtained for the general DCNN, the Hopfield neural networks (HNNs), and delayed HNNs with monotonic nondecreasing and nonconstant activation functions View full abstract»

• ### Correction to &ldquo;Noise Figure Optimization of Inductively-Degenerated CMOS LNA's With Integrated Gate Inductors&rdquo;

Publication Year: 2007, Page(s): 925
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In the above title paper (ibid., vol. 53, no. 7, pp. 1409-1422, Jul 06), changes were made to various equations. View full abstract»

• ### Corrections to &ldquo;Expandable Networks for Neuromorphic Chips&rdquo;

Publication Year: 2007, Page(s):925 - 926
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In the above titled paper (ibid., vol. 54, no. 2, pp. 301-311, Feb 07), changes were made to Figures 6-8. View full abstract»

• ### A Comment on &ldquo;Cryptographic Applications of Brahmagupta&ndash;Bh&atilde;skara Equation&rdquo;

Publication Year: 2007, Page(s):927 - 928
Cited by:  Papers (8)
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Murthy and Swamy proposed a symmetric key encryption system based on Brahmagupta-Bhaskara equation over GF(p). In this comment, we show that breaking this system is equivalent to solving a set of linear equations over the field of rational numbers. Our attack, typically, requires as low as three known plaintext-ciphertext pairs and allows the cryptanalyst to fully recover the secret key View full abstract»

## Aims & Scope

The theory, analysis, design, and practical implementations of circuits, and the application of circuit techniques to systems and to signal processing.

Full Aims & Scope

## Meet Our Editors

Editor-in-Chief
Andreas Demosthenous
Dept. Electronic & Electrical Engineering
University College London
London WC1E 7JE, UK