Showing papers on "Dynamic range published in 2012"

Developing self‐mixing interferometry for instrumentation and measurements

Abstract: In this review, self-mixing interferometry (SMI), a new configuration of interferometry, is discussed. SMI has practical advantages compared to standard interferometry, for example SMI does not require any optical part external to the laser chip and can be employed in a variety of measurements. Applications range from the traditional measurements related to optical pathlength – like displacement, small-amplitude vibrations, velocity – to sensing of weak optical echoes – for return loss and isolation factor measurements, CD readout and scroll sensing – and also, a special feature because of the interaction with the medium, measurements of physical parameters, like the laser linewidth, coherence length, and the alfa factor. Because it is also a coherent detection scheme, the SMI works close to the quantum limit of the received field, typically -90 dBm, so that minimum detectable amplitudes of 100 pm/ √Hz are currently achieved upon operation on diffusive targets, whereas a corner cube allows half-wavelength counting mode – or 0.5 μm resolution – on a dynamic range up to 2 m and more. With its compact setup, the SMI is easy to deploy in the field and can interface a variety of experiments – from MEMS testing to rotating machines vibration testing to pickup of biological motility. The illustration shows a double-channel, differential SMI incorporated in a thermomechanical test equipment to trace the mechanical hysteresis cycle of the beads of a motor-engine brake.

Apparatus and method for dynamic range transforming of images

Abstract: An image processing apparatus comprises a receiver (201) for receiving an image signal comprising an encoded image. Another receiver (1701) receives a data signal from a display (107) where the data signal comprises a data field that comprises a display dynamic range indication of the display (107). The display dynamic range indication comprises at least one luminance specification for the display. A dynamic range processor (203) is arranged to generate an output image by applying a dynamic range transform to the encoded image in response to the display dynamic range indication. An output (205) outputs an output image signal comprising the output image to the display. The transform may furthermore be performed in response to a target display reference indicative of a dynamic range of display for which the encoded image is encoded. The invention may be used to generate an improved High Dynamic Range (HDR) image from e.g. a Low Dynamic Range (LDR) image, or vice versa.

Coherence Pattern-Guided Compressive Sensing with Unresolved Grids

Abstract: Highly coherent sensing matrices arise in discretization of continuum imaging problems such as radar and medical imaging when the grid spacing is below the Rayleigh threshold. Algorithms based on techniques of band exclusion (BE) and local optimization (LO) are proposed to deal with such coherent sensing matrices. These techniques are embedded in the existing compressed sensing algorithms, such as Orthogonal Matching Pursuit (OMP), Subspace Pursuit (SP), Iterative Hard Thresholding (IHT), Basis Pursuit (BP), and Lasso, and result in the modified algorithms BLOOMP, BLOSP, BLOIHT, BP-BLOT, and Lasso-BLOT, respectively. Under appropriate conditions, it is proved that BLOOMP can reconstruct sparse, widely separated objects up to one Rayleigh length in the Bottleneck distance independent of the grid spacing. One of the most distinguishing attributes of BLOOMP is its capability of dealing with large dynamic ranges. The BLO-based algorithms are systematically tested with respect to four performance metrics: dynamic range, noise stability, sparsity, and resolution. With respect to dynamic range and noise stability, BLOOMP is the best performer. With respect to sparsity, BLOOMP is the best performer for high dynamic range, while for dynamic range near unity BP-BLOT and Lasso-BLOT with the optimized regularization parameter have the best performance. In the noiseless case, BP-BLOT has the highest resolving power up to certain dynamic range. The algorithms BLOSP and BLOIHT are good alternatives to BLOOMP and BP/Lasso-BLOT: they are faster than both BLOOMP and BP/Lasso-BLOT and share, to a lesser degree, BLOOMP's amazing attribute with respect to dynamic range. Detailed comparisons with the algorithms Spectral Iterative Hard Thresholding (SIHT) and the frame-adapted BP demonstrate the superiority of the BLO-based algorithms for the problem of sparse approximation in terms of highly coherent, redundant dictionaries.

A Wideband, Low-Noise Superconducting Amplifier with High Dynamic Range

Abstract: Amplifiers are ubiquitous in electronics and play a fundamental role in a wide range of scientific measurements. From a user's perspective, an ideal amplifier has very low noise, operates over a broad frequency range, and has a high dynamic range - it is capable of handling strong signals with little distortion. Unfortunately, it is difficult to obtain all of these characteristics simultaneously. For example, modern transistor amplifiers offer multi-octave bandwidths and excellent dynamic range. However, their noise remains far above the fundamental limit set by the uncertainty principle of quantum mechanics. Parametric amplifiers, which predate transistor amplifiers and are widely used in optics, exploit a nonlinear response to transfer power from a strong pump tone to a weak signal. If the nonlinearity is purely reactive, ie. nondissipative, in theory the amplifier noise can reach the quantum-mechanical limit. Indeed, microwave frequency superconducting Josephson parametric amplifiers do approach the quantum limit, but generally are narrow band and have very limited dynamic range. In this paper, we describe a superconducting parametric amplifier that overcomes these limitations. The amplifier is very simple, consisting only of a patterned metal film on a dielectric substrate, and relies on the nonlinear kinetic inductance of a superconducting transmission line. We measure gain extending over 2 GHz on either side of an 11.56 GHz pump tone, and we place an upper limit on the added noise of the amplifier of 3.4 photons at 9.4 GHz. Furthermore, the dynamic range is very large, comparable to microwave transistor amplifiers, and the concept can be applied throughout the microwave, millimeter-wave and submillimeter-wave bands.

Analog and digital self-interference cancellation in full-duplex MIMO-OFDM transceivers with limited resolution in A/D conversion

Abstract: We analyze the performance of full-duplex MIMO-OFDM transceivers with subtractive self-interference cancellation in analog and/or digital domain, ie, before and/or after analog-to-digital converters (ADCs) In particular, the non-ideal ADCs are modeled by assuming uniform b-bit quantization which allows us to derive closed-form expressions for the signal to interference and noise ratio when including the effects of the residual self-interference due to imperfect cancellation and the clipping-plus-quantization noise due to the limited dynamic range of ADCs Consequently, this facilitates a study on the fundamental trade-off between ADC resolution, maximum transmit power, minimum physical isolation and sufficient signal to self-interference ratio needed to avoid receiver saturation We also highlight the benefit of combining analog and digital cancellation: if the former attenuates interference sufficiently well such that all received signals fit within the limited dynamic range of ADCs, the latter can handle the residual self-interference efficiently

A Low-Noise High Intrascene Dynamic Range CMOS Image Sensor With a 13 to 19b Variable-Resolution Column-Parallel Folding-Integration/Cyclic ADC

Abstract: A low temporal noise and high dynamic range CMOS image sensor is developed. A 1Mpixel CMOS image sensor with column-parallel folding-integration and cyclic ADCs has 80μVrms (1.2e-) temporal noise, 82 dB dynamic range using 64 samplings in the folding-integration ADC mode. Very high variable gray-scale resolution of 13b through 19b is attained by changing the number of samplings of pixel outputs. The implemented CMOS image sensor using a 0.18-μm technology has the sensitivity of 10-V/lx·s, the conversion gain of 67- μV/e-, and linear digital code range of more than 4 decades.

Portable Real-Time Microwave Camera at 24 GHz

Abstract: This paper presents a microwave camera built upon a two-dimensional array of switchable slot antennas. The camera borrows from modulated scattering techniques to improve isolation among the array elements. The camera was designed to measure vector electric field distribution, be compact, portable, battery operated, possess high dynamic range, and be capable of producing real-time images at video frame-rate. This imaging system utilizes PIN diode-loaded resonant elliptical slot antennas as its array elements integrated in a simple and relatively low-loss waveguide network thus reducing the complexity, cost and size of the array. The sensitivity and dynamic range of this system is improved by utilizing a custom-designed heterodyne receiver and matched filter for demodulation. The performance of the multiplexing scheme, noise-floor and dynamic range of the receivers are presented as well. Sources of errors such as mutual-coupling and array response dispersion are also investigated. Finally, utilizing this imaging system for various applications such as 2-D electric field mapping, and nondestructive testing is demonstrated.

Digital Dynamic Range Compressor Design—A Tutorial and Analysis

Abstract: Dynamic range compression, despite being one of the most widely used audio effects, is still poorly understood, and there is little formal knowledge and analysis of compressor design techniques. In this tutorial we describe several different approaches to digital dynamic range compressor design. Digital implementations of several classic analog approaches are given, as well as designs from recent literature, and new approaches that address possible issues. Several design techniques are analyzed and compared, including RMS and peak–based approaches, feedforward and feedback designs, and linear and log domain level detection. We explain what makes the designs sound different and provide metrics to analyze their quality. Finally, we provide recommendations for high performance compressor design.

A Compact Dynamic-Performance-Improved Current-Steering DAC With Random Rotation-Based Binary-Weighted Selection

Abstract: Conventional binary-weighted current-steering DACs are generally operated with current groups where each group is binary-weighted and formed with predetermined members of a unit current-source array. This paper proposes a random rotation-based binary-weighted selection (RRBS) that efficiently performs dynamic-element matching (DEM) by randomly rotating the sequence of these units to form new binary-weighted current groups for each DAC output. Without using binary-to-thermometer decoders, RRBS features its simplicity and compactness of DEM realization. Compared to conventional binary-weighted DACs, RRBS DACs are insensitive to the mismatch of small-size current-sources and exhibit better dynamic performance. A 10-bit RRBS DAC is implemented with only 0.034 mm2 in a standard 1P6M 1.8 V 0.18 μm CMOS process. Measured performance achieves >;61 dB spurious-free dynamic range (SFDR) in the Nyquist bandwidth with 500 MS/s, while its active area is less than one-tenth of that required by state-of-the-art 10-bit current steering DACs. To the best of our knowledge, the proposed RRBS implements the smallest area for high-speed current-steering DACs up to now. Its SFDR is also comparable to that of 12-bit published designs. Three popular figures-of-merit (FOMs) are used to compare this design with other state-of-the-art 10-12-bit DACs, with the proposed design performing best with 2 FOMs.

Highly Linear Broadband Optical Modulator Based on Electro-Optic Polymer

Abstract: In this paper, we present the design, fabrication, and characterization of a traveling-wave directional coupler modulator based on electro-optic polymer, which is able to provide both high linearity and broad bandwidth. The high linearity is realized by introducing Δβ -reversal technique in the two-domain directional coupler. A traveling-wave electrode is designed to function with bandwidth-length product of 302 GHz·cm , by achieving low microwave loss, excellent impedance matching, and velocity matching, as well as smooth electric-field profile transformation. The 3-dB bandwidth of the device is measured to be 10 GHz. The spurious-free dynamic range of 110 dB ±3 Hz2/3 is measured over the modulation frequency range of 2-8 GHz. To the best of our knowledge, such high linearity is first measured at the frequency up to 8 GHz. In addition, a 1 × 2 multimode interference 3-dB splitter, a photobleached refractive index taper, and a quasi-vertical taper are used to reduce the optical insertion loss of the device.

Re-engineering electrochemical biosensors to narrow or extend their useful dynamic range

Abstract: Here we demonstrate two convenient methods to extend and narrow the useful dynamic range of a model electrochemical DNA sensor. We did so by combining DNA probes of different target affinities but with similar specificity on the same electrode. We were able to achieve an extended dynamic response spanning 3 orders of magnitude in target concentration. Using a different strategy we have also narrowed the useful dynamic range of an E-DNA sensor to only an 8-fold range of target concentrations.

High-Range Angular Rate Sensor Based on Mechanical Frequency Modulation

Abstract: We report, for the first time, an angular rate sensor based on mechanical frequency modulation (FM) of the input rotation rate. This approach tracks the resonant frequency split between two X - Y symmetric high-Q mechanical modes of vibration in a microelectromechanical systems Coriolis vibratory gyroscope to produce a frequency-based measurement of the input angular rate. The system is enabled by a combination of a MEMS vibratory high-Q gyroscope and a new signal processing scheme which takes advantage of a previously ignored gyroscope dynamic effect. A real-time implementation of the quasi-digital angular rate sensor was realized using two digital phase-locked loops and experimentally verified using a silicon MEMS quadruple mass gyroscope (QMG). Structural characterization of a vacuum- packaged QMG showed Q factors on the order of one million over a wide temperature range from -40 °C to +100°C with a relative x/y mismatch of Q of 1 %. Temperature characterization of the FM rate sensor exhibited less than 0.2% variation of the angular rate response between 25°C and 70 °C environments, enabled by the self-calibrating differential frequency detection. High-speed rate table characterization of the FM angular rate sensor demonstrated a linear range of 18 000 deg/s (50 r/s, limited by the setup) with a dynamic range of 128 dB. Interchangeable operation of the QMG transducer in conventional amplitude- modulated and new FM regimes provides a 156-dB dynamic range.

Dynamic Time Over Threshold Method

Abstract: The time over threshold (TOT) method has several advantages over direct pulse height analysis based on analog to digital converters (ADCs). A key advantage is the simplicity of the conversion circuit which leads to a high level of integration and a low power consumption. The TOT technique is well suited to build multi-channel readout systems for pixelated detectors as described in our previous work that also exploits the Pulse Width Modulation (PWM) method. The main limitation of the TOT technique is that the relation between the input charge to be measured and the width of the encoded pulse is strongly non-linear. Dynamic range limitation is also an issue. To address these aspects, we propose a new time over threshold conversion circuit where the threshold of the comparator is dynamically changed instead of being constant. We call this scheme the “dynamic TOT method”. We show that it improves linearity and dynamic range. It also shortens the duration of measured pulses leading to higher counting rates. We present a short analysis that explains how the ideal linear input charge to TOT transfer function can theoretically be obtained. We describe the results obtained with a test circuit built from discrete components and present several of the spectrums obtained with crystal detectors and a radioactive source. The proposed method can be used for applications like Positron Emission Tomography (PET) that require moderate energy resolution.

The Dexela 2923 CMOS X-ray detector: A flat panel detector based on CMOS active pixel sensors for medical imaging applications

Abstract: Complementary metal-oxide-semiconductors (CMOS) active pixel sensors (APS) have been introduced recently in many scientific applications. This work reports on the performance (in terms of signal and noise transfer) of an X-ray detector that uses a novel CMOS APS which was developed for medical X-ray imaging applications. For a full evaluation of the detector's performance, electro-optical and X-ray characterizations were carried out. The former included measuring read noise, full well capacity and dynamic range. The latter, which included measuring X-ray sensitivity, presampling modulation transfer function (pMTF), noise power spectrum (NPS) and the resulting detective quantum efficiency (DQE), was assessed under three beam qualities (28 kV, 50 kV (RQA3) and 70 kV (RQA5) using W/Al) all in accordance with the IEC standard. The detector features an in-pixel option for switching the full well capacity between two distinct modes, high full well (HFW) and low full well (LFW). Two structured CsI:Tl scintillators of different thickness (a thin one for high resolution and a thicker one for high light efficiency) were optically coupled to the sensor array to optimize the performance of the system for different medical applications. The electro-optical performance evaluation of the sensor results in relatively high read noise (∼360 e -), high full well capacity (∼1.5×10 6 e -) and wide dynamic range (∼73 dB) under HFW mode operation. When the LFW mode is used, the read noise is lower (∼165) at the expense of a reduced full well capacity (∼0.5×10 6 e -) and dynamic range (∼69 dB). The maximum DQE values at low frequencies (i.e. 0.5 lp/mm) are high for both HFW (0.69 for 28 kV, 0.71 for 50 kV and 0.75 for 70 kV) and LFW (0.69 for 28 kV and 0.7 for 50 kV) modes. The X-ray performance of the studied detector compares well to that of other mammography and general radiography systems, obtained under similar experimental conditions. This demonstrates the suitability of the detector for both mammography and general radiography, with the use of appropriate scintillators. The high DQE values obtained under low mammographic exposures (up to 0.65 for 22.3 μGy) matches the demand for high detectability in imaging of the dense breast. © 2012 Elsevier B.V.

Long-range vibration sensor based on correlation analysis of optical frequency-domain reflectometry signals

Abstract: We present a novel method to achieve a space-resolved long- range vibration detection system based on the correlation analysis of the optical frequency-domain reflectometry (OFDR) signals By performing two separate measurements of the vibrated and non-vibrated states on a test fiber, the vibration frequency and position of a vibration event can be obtained by analyzing the cross-correlation between beat signals of the vibrated and non-vibrated states in a spatial domain, where the beat signals are generated from interferences between local Rayleigh backscattering signals of the test fiber and local light oscillator Using the proposed technique, we constructed a standard single-mode fiber based vibration sensor that can have a dynamic range of 12 km and a measurable vibration frequency up to 2 kHz with a spatial resolution of 5 m Moreover, preliminarily investigation results of two vibration events located at different positions along the test fiber are also reported

A 1500 fps Highly Sensitive 256 $\,\times\,$ 256 CMOS Imaging Sensor With In-Pixel Calibration

Abstract: High-speed CMOS imaging sensors (CIS) normally have low sensitivity because of the large integration capacitance. They also have high noise because pixel circuits cannot implement correlated double sampling (CDS) to remove the pixel reset noise. For applications, such as micro-computed tomography (micro-CT), this is a major limitation. In this work, we developed a technique to achieve high sensitivity and low noise for high-speed CIS. To maximize the sensitivity, we designed a new capacitive transimpedance amplifier (CTIA) pixel with a tiny metal-oxide-metal capacitor. The pixel circuit also implements CDS. As a result, the temporal noise is greatly reduced, and the sensitivity improves dramatically. To compensate the mismatch of small integration capacitors across the pixel array, an on-chip calibration scheme with in-pixel circuits is developed. Fully differential column circuits are designed to suppress the power supply injection in the large array of high-speed column circuits. A successive-approximation analog-to-digital (SAR ADC) is designed to achieve 10-bit resolution and to fit in the 15-μm column pitch. For testing modes, column circuits are configured into a two-step ADC to provide 13-bit dynamic range. The 256 × 256 CIS design is fabricated in a 0.18-μm CMOS process. The imager samples up to 1500 fps. The pixel integration capacitor is 0.7 fF, which enables 68.5 V/lux · s sensitivity under the white illumination. The CIS temporal noise is 13.6e-. This sensitivity and noise performances are much better than previous high-speed CIS benchmark designs. Running at 1500 fps, the CIS can capture recognizable images with illumination down to 1 lux. The on-chip calibration suppresses the fixed-pattern noise lower than 0.52%. The prototype chip consumes 390 mW of power.

The GOTTHARD charge integrating readout detector: design and characterization

Abstract: A charge integrating readout ASIC (Application Specific Integrated Circuit) for silicon strip sensors has been developed at PSI in collaboration with DESY. The goal of the project is to provide a charge integrating readout system able to cope with the pulsed beam of XFEL machines and at the same time to retain the high dynamic range and single photon resolution performances typical for photon counting systems. The ASIC, designed in IBM 130 nm CMOS technology, takes advantage of its three gain stages with automatic stage selection to achieve a dynamic range of 10000 12 keV photons and a noise better than 300 e.n.c.. The 4 analog outputs of the ASIC are optimized for speed, allowing frame rates higher than 1 MHz, without compromises on linearity and noise performances. This work presents the design features of the ASIC, and reports the characterization results of the chip itself.

CMOS detector arrays in a virtual 10-kilopixel camera for coherent terahertz real-time imaging

Abstract: We demonstrate the principle applicability of antenna-coupled complementary metal oxide semiconductor (CMOS) field-effect transistor arrays as cameras for real-time coherent imaging at 591.4 GHz. By scanning a few detectors across the image plane, we synthesize a focal-plane array of 100×100 pixels with an active area of 20×20 mm2, which is applied to imaging in transmission and reflection geometries. Individual detector pixels exhibit a voltage conversion loss of 24 dB and a noise figure of 41 dB for 16 μW of the local oscillator (LO) drive. For object illumination, we use a radio-frequency (RF) source with 432 μW at 590 GHz. Coherent detection is realized by quasioptical superposition of the image and the LO beam with 247 μW. At an effective frame rate of 17 Hz, we achieve a maximum dynamic range of 30 dB in the center of the image and more than 20 dB within a disk of 18 mm diameter. The system has been used for surface reconstruction resolving a height difference in the μm range.

Layer Decomposition in Hierarchical VDR Coding

Abstract: Techniques use multiple lower bit depth codecs to provide higher bit depth, high dynamic range, images from an upstream device to a downstream device. A base layer and one or more enhancement layers may be used to carry video signals, wherein the base layer cannot be decoded and viewed on its own. Lower bit depth input image data to base layer processing may be generated from higher bit depth high dynamic range input image data via advanced quantization to minimize the volume of image data to be carried by enhancement layer video signals. The image data in the enhancement layer video signals may comprise residual values, quantization parameters, and mapping parameters based in part on a prediction method corresponding to a specific method used in the advanced quantization. Adaptive dynamic range adaptation techniques take into consideration special transition effects, such as fade-in and fade-outs, for improved coding performance.

A 0.5-V 35- $ \mu $ W 85-dB DR Double-Sampled $\Delta\Sigma$ Modulator for Audio Applications

Abstract: This paper presents a 0.5-V 1.5-bit double-sampled ΔΣ modulator for audio applications. Unlike existing double-sampled designs, the proposed double-sampled ΔΣ modulator employs an input-feedforward topology to reduce internal signal swings, thereby relaxing design requirements for the low-voltage building blocks and reducing distortion. Moreover, in order to avoid instability and noise shaping degradation, the proposed architecture restores the noise transfer function (NTF) of the double-sampled modulator to its single-sampled equivalent with the help of compensation loops. In the circuit implementation, the proposed fully-differential amplifier adopts an inverter output stage and a common-mode feedback (CMFB) circuit with a global feedback loop in order to reduce power consumption. A resistor-string-reference switch matrix based on a direct summation quantizer is used to simplify the analog compensation loop. The chip prototype has been fabricated in a 0.13-μm CMOS technology with a core area of 0.57 mm2. The measured results show that when operating from a 0.5-V supply and clocked at 1.25 MHz, the modulator achieves a peak signal-to-noise and distortion ratio (SNDR) of 81.7 dB, a peak signal-to-noise ratio (SNR) of 82.4 dB and a dynamic range (DR) of 85.0 dB while consuming 35.2 μW for a 20-kHz signal bandwidth.

Improved performance of TES bolometers using digital feedback

Abstract: Voltage biased, frequency multiplexed TES bolometers have become a widespread tool in mm-wave astrophysics. However, parasitic impedance and dynamic range issues can limit stability, performance, and multiplexing factors. Here, we present novel methods of overcoming these challenges, achieved through digital feedback, implemented on a Field-Programmable Gate Array (FPGA). In the first method, known as Digital Active Nulling (DAN), the current sensor (e.g. SQUID) is nulled in a separate digital feedback loop for each bolometer frequency. This nulling removes the dynamic range limitation on the current sensor, increases its linearity, and reduces its effective input impedance. Additionally, DAN removes constraints on wiring lengths and maximum multiplexing frequency. DAN has been fully implemented and tested. Integration for current experiments, including the South Pole Telescope, will be discussed. We also present a digital mechanism for strongly increasing stability in the presence of large series impedances, known as Digitally Enhanced Voltage Bias (DEVB).

Graphene FET-Based Zero-Bias RF to Millimeter-Wave Detection

Abstract: We report direct radio-frequency (RF) and millimeter-wave detection of epitaxial graphene field-effect transistors (FETs) up to 110 GHz with no dc biases applied, leveraging the nonlinearity of the channel resistance A linear dynamic range of >; 40 dB was measured, providing at least 20-dB greater linear dynamic range compared to conventional CMOS detectors at transistor level The measured noise power of the graphene FETs was ~75 × 10-18 V2/Hz at zero bias and without 1/f noise At a 50-Ω load, measured detection responsivity was 71 V/W at 2 GHz to 33 V/W at 110 GHz The noise-equivalent power at 110 GHz was estimated to be ~80 pW/Hz05 For the first time, we demonstrated graphene FETs as zero-bias ultrawideband direct RF detectors with comparable or better performance than state-of-the-art FET-based detectors without dc biases applied

Reconfigurable Dual-Channel Multiband RF Receiver for GPS/Galileo/BD-2 Systems

Abstract: A fully integrated dual-channel multiband RF receiver is designed and implemented for next-generation global navigation satellite systems (GNSSs) in a 018-μm CMOS process Its two reconfigurable signal channels can simultaneously process any two types of 2-, 4-, or 20-MHz bandwidth signals mainly located around the RF bands of 12 and 157 GHz for GPS, Galileo, and BD-2 (aka Compass) systems, while achieving better performance (die area, noise figure, gain dynamic range) than other state-of-the-art GNSS receivers A digital automatic gain control loop consisting of a variable gain amplifier and nonuniform 4-bit ADC is utilized to improve the receiver's robustness and performance in the presence of interferences While drawing 25-mA current per channel from a 18-V supply, this RF receiver achieves a total noise figure of 25 dB/27 dB at 12/157 GHz, an image rejection of 28 dB, a maximum voltage gain of 110 dB, a gain dynamic range of 73 dB, and an input-referred 1-dB compression point of -58 dBm, with an active die area of 24 mm2 for single channel

High-resolution current sensor utilizing nanocrystalline alloy and magnetoelectric laminate composite.

Abstract: A self-powered currentsensor consisting of the magnetostrictive/piezoelectric laminatecomposite and the high-permeability nanocrystalline alloys is presented. The induced vortexmagnetic flux is concentrated and amplified by using an optimized-shape nanocrystalline alloy of FeCuNbSiB into the magnetoelectric laminatecomposite; this optimization allows improving the sensitivity significantly as well as increasing the saturation of the currentsensor. The main advantages of this currentsensor are its large dynamic range and ability to measurecurrents accurately. An analytical expression for the relationship between current and voltage is derived by using the magnetic circuit principle, which predicts the measured sensitivity well. The experimental results exhibit an approximately linear relationship between the electric current and the induced voltage. The dynamic range of this sensor is from 0.01 A to 150 A, and a small electric current step-change of 0.01 A can be clearly distinguished at the power-line frequency of 50 Hz. We demonstrate that the currentsensor has a flat operational frequency in the range of 1 Hz–20 kHz relative to a conventional induction coil. The currentsensor indicates great potentials for monitoring conditions of electrical facilities in practical applications due to the large dynamic range, linear sensitivity, wide bandwidth frequency response, and good time stability.

A Low-Noise High-Dynamic-Range 17-b 1.3-Megapixel 30-fps CMOS Image Sensor With Column-Parallel Two-Stage Folding-Integration/Cyclic ADC

Abstract: A 1.3-megapixel CMOS image sensor (CIS) with digital correlated double sampling and 17-b column-parallel two-stage folding-integration/cyclic analog-to-digital converters (ADCs) is developed. The image sensor has 0.021-erms- vertical fixed pattern noise, 1.2-erms- pixel temporal noise, and 85.0-dB dynamic range using 32 samplings in the folding-integration ADC mode. Despite the large number of samplings (32 times), the prototype image sensor is demonstrated at the video rate operation of 30 Hz by the new architecture of the proposed ADCs and the high-performance peripheral logic (or digital) parts using low-voltage differential signaling circuit. The developed 17-b CIS has no visible quantization noise at very low light level of 0.01 lx because of high grayscale resolution where 1LSB = 0.1-. The implemented CIS using 0.18- μm technology has the sensitivity of 20 V/lx ·s and the pixel conversion gain of 82 μV/e-.

Imaging X-ray detector front-end with high dynamic range: IDeF-X HD

Abstract: Presented circuit, IDeF-X HD (Imaging Detector Front-end) is a member of the IDeF-X ASICs family for space applications. It has been optimized for a half millimeter pitch CdTe or CdZnTe pixelated detector arranged in 16×16 array. It is aimed to operate in the hard X-ray range from few keV up to 250 keV or more. The ASIC has been realized in AMS 0.35 μm CMOS process. The IDeF-X HD is a 32 channel analog front-end with self-triggering capability. The architecture of the analog channel includes a chain of charge sensitive amplifier with continuous reset system and non-stationary noise suppressor, adjustable gain stage, pole-zero cancellation stage, adjustable shaping time low pass filter, baseline holder and peak detector with discriminator. The power consumption of the IDeF-X HD is 800 μW per channel. With the in-channel variable gain stage the nominal 250 keV dynamic range of the ASIC can be extended up to 1 MeV anticipating future applications using thick sensors. Measuring the noise performance without a detector at the input with minimized leakage current (programmable) at the input, we achieved ENC of 33 electrons rms at 10.7 μs peak time. Measurements with CdTe detector show good energy resolution FWHM of 1.1 keV at 60 keV and 4.3 keV at 662 keV with detection threshold below 4 keV. In addition, an absolute temperature sensor has been integrated with resolution of 1.5 °C.

A 16 MHz BW 75 dB DR CT $\Delta\Sigma$ ADC Compensated for More Than One Cycle Excess Loop Delay

Abstract: The maximum sampling rate of a continuous-time ΔΣ modulator in a given process is limited by the minimum flash ADC delay that can be realized. Excess loop delay compensation techniques that are widely used can compensate for delays up to half a clock cycle. Addition of a fast loop outside the flash ADC can break this limit and compensate for one and half clock cycles of delay at the cost of reducing the order of noise shaping by one. This technique, along with a low latency flash ADC, and a delay free calibrated DAC, result in a lowpass continuous-time ΔΣ ADC with the highest reported sampling rate in a 0.18 m process. The prototype occupies 0.68 mm2 , consumes 47.6 mW, and operates at 800 MS/s. In a 16 MHz bandwidth (oversampling ratio of 25), the dynamic range, maximum signal to noise ratio, and maximum signal to noise and distortion ratios are 75 dB, 67 dB, and 65 dB respectively. In a 32 MHz bandwidth, the dynamic range, maximum signal to noise ratio, and maximum signal to noise and distortion ratios are 64 dB, 57 dB, and 57 dB, respectively.

Event-Driven GHz-Range Continuous-Time Digital Signal Processor With Activity-Dependent Power Dissipation

Abstract: Presented is a clockless, continuous-time (CT) GHz processor that bypasses some of the limitations of conventional digital and analog implementations. Per-edge digital signal encoding is used for parallel processing of continuous-time samples with a temporal spacing as narrow as 15 ps, generated by a 3-b CT flash ADC. Parallel digital delay chains and programmable charge pumps realize the asynchronous filtering operation, each consuming negligible power while awaiting a new sample. A six-tap CT ADC and CT digital FIR processor system occupies 0.07 mm2 and achieves dynamic range of over 20 dB in the 0.8-3.2-GHz signal range. The system's rate of operations automatically adapts to the signal, thus causing its power dissipation to vary in the range of 1.1 to 10 mW according to input activity.

Photon-Counting Optical Time-Domain Reflectometry Using a Superconducting Nanowire Single-Photon Detector

Abstract: A novel photon-counting optical time-domain reflectometry (ν-OTDR) based on superconducting nanowire single-photon detector (SNSPD) is proposed and demonstrated experimentally. Benefiting from the low noise equivalent power (NEP), high repetition rate and low timing jitter of the SNSPD, our ν-OTDR system achieves a dynamic range of 22 dB after measurement time of 15 minutes. This obtainable dynamic range corresponds to a sensing length of 110 km. The system exhibits 6.0 cm spatial resolution at the end of 2 km and 1.1 m spatial resolution at the end of 26 km standard single-mode fiber. Considering the performance we obtained now and the increasing improvement of the fabrication technology, the SNSPD is promising in the field of fiber sensors.