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Dynamic range

About: Dynamic range is a research topic. Over the lifetime, 7576 publications have been published within this topic receiving 101739 citations. The topic is also known as: DNR & DR.


Papers
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Journal ArticleDOI
TL;DR: An area-efficient and robust integrated test core for mixed-signal circuits is described, capable of both generating arbitrary band-limited waveforms and coherently digitizing arbitrary periodic analog waveforms for DSP-based test and measurement.
Abstract: An area-efficient and robust integrated test core for mixed-signal circuits is described. The core consists of a completely digital implementation, except for a simple reconstruction filter and a comparator. It is capable of both generating arbitrary band-limited waveforms (for excitation purposes) and coherently digitizing arbitrary periodic analog waveforms (for DSP-based test and measurement). Several prototypes were fabricated in a triple-metal 3.3-V 0.35-/spl mu/m CMOS process, and were demonstrated to perform various curve tracing, oscilloscope, and spectrum analysis tasks at a clock rate of 20 MHz (limited by our experimental setup). Designed for 8 bits of quantization, a spurious-free dynamic range (SFDR) of 65 dB at 500 KHz and 61 dB at Nyquist (20.001 MHz) was demonstrated using our prototypes. High-frequency narrow-band signals (extending into the gigahertz range) have been captured through subsampling and the use of a high-bandwidth front-end sampling network. Similarly, circuit phenomena that are broadband in nature were measured by using a delayed-clock subsampling mechanism in which the digitizer sample clock is consistently delayed over multiple runs of the periodic test signal. Delaying the clock is performed using a voltage-controlled delay line tuned by a self-biased delay-locked loop, which allowed for a timing resolution of about one gate delay (/spl sim/200 ps). The proposed test core occupies an area equivalent to only about 7000 standard-cell 2-input NAND gates.

77 citations

PatentDOI
TL;DR: In this paper, a medical ultrasonic imaging system uses an adaptive multi-dimensional back-end mapping stage to eliminate loss of information in the back end, minimize any back end quantization noise, reduce or eliminate electronic noise, and map the local average of soft tissue to a target display value throughout the image.
Abstract: A medical ultrasonic imaging system uses an adaptive multi-dimensional back-end mapping stage to eliminate loss of information in the back-end, minimize any back-end quantization noise, reduce or eliminate electronic noise, and map the local average of soft tissue to a target display value throughout the image. The system uses spatial variance to identify regions of the image corresponding substantially to soft tissue and a noise frame acquired with the transmitters turned off to determine the mean system noise level. The system then uses the mean noise level and the identified regions of soft tissue to both locally and adaptively set various back-end mapping stages, including the gain and dynamic range.

77 citations

Proceedings ArticleDOI
08 Aug 2004
TL;DR: An adaptive exposure range adjustment technique for minimizing the number of exposures necessary for capturing the extreme dynamic range of natural illumination environments that include the sun and sky, which has presented a challenge for traditional high dynamic range photography processes.
Abstract: We present a technique for capturing the extreme dynamic range of natural illumination environments that include the sun and sky, which has presented a challenge for traditional high dynamic range photography processes. We find that through careful selection of exposure times, aperture, and neutral density filters that this full range can be covered in seven exposures with a standard digital camera. We discuss the particular calibration issues such as lens vignetting, infrared sensitivity, and spectral transmission of neutral density filters which must be addressed. We present an adaptive exposure range adjustment technique for minimizing the number of exposures necessary. We demonstrate our results by showing time-lapse renderings of a complex scene illuminated by high-resolution, high dynamic range natural illumination environments.

77 citations

Journal ArticleDOI
TL;DR: In this article, a detailed theoretical analysis of the input power dynamic range for gain-clamped semiconductor optical amplifier (GC-SOA) gates at 10 Gb/s is presented.
Abstract: A detailed theoretical investigation of the input power dynamic range for gain-clamped semiconductor optical amplifier (GC-SOA) gates at 10 Gb/s is presented. We show that although the gain is clamped, the dynamic changes of the carrier distribution in the GC-SOA causes pattern effects on a time scale given by the relaxation frequency of the GC-SOA. Combined with a higher noise figure compared to a conventional SOA, this results in a dynamic range only /spl sim/0.5 dB better than for an optimized SOA gate.

77 citations

Journal ArticleDOI
TL;DR: In this article, a digital ΔΣ fractional-N frequency synthesizer for 4G communication standards is presented which is able to achieve wide loop bandwidth while producing low fractional spurs.
Abstract: A digital ΔΣ fractional-N frequency synthesizer for 4G communication standards is presented which is able to achieve wide loop bandwidth while producing low fractional spurs. The loop adopts a fractional-N divider based on a phase interpolator, allowing to shrink the TDC dynamic range and to improve its linearity. A dynamic-element matching algorithm is employed to further improve TDC linearity and an original correlation algorithm is used to correct for the phase interpolator mismatches. Both digital algorithms operate in background and they are demonstrated to be concurrently effective in reducing in-band fractional spurs below -57 dBc. The circuit is fully integrated in a 65 nm CMOS process and it synthesizes a carrier in the 3.0-3.6 GHz range from a 40 MHz crystal reference with 40 Hz resolution. It achieves -104-dBc/Hz phase noise at 400-kHz offset and a 3.2-MHz maximum loop bandwidth. The synthesizer dissipates 80 mW and occupies 0.4 mm2.

77 citations


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Performance
Metrics
No. of papers in the topic in previous years
YearPapers
2023176
2022383
2021189
2020265
2019325
2018334