Topic
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 published on a yearly basis
Papers
More filters
Patent•
01 Oct 1996TL;DR: In this paper, an imager using an array of photodiodes that does not require non-standard voltages nor multiphase clocking schemes and retains good linearity with low fixed pattern and random noise generation while requiring a minimum of silicon area is described.
Abstract: An imager using an array of photodiodes that does not require non-standard voltages nor multiphase clocking schemes and retains good linearity with low fixed pattern and random noise generation while requiring a minimum of silicon area is described.
46 citations
TL;DR: In this article, a linear-mode optical sensor for the feasible applications of unmanned vehicle LiDAR systems, in which a pulsed-erbium fiber laser is exploited as a light source and a 16-channel transimpedance amplifier (TIA) array is utilized in an optical Rx module with low-cost InGaAs PIN photodiodes.
Abstract: This paper presents a linear-mode optical sensor for the feasible applications of unmanned vehicle LiDAR systems, in which a pulsed-erbium fiber laser is exploited as a light source and a 16-channel transimpedance amplifier (TIA) array is utilized in an optical Rx module with low-cost InGaAs PIN photodiodes. In particular, a voltage-mode CMOS feedforward (VCF-TIA) is newly proposed to achieve twice higher transimpedance gain with lower noise and similar bandwidth characteristics than a conventional inverter TIA, thereby enabling longer detection. Test chips of the 16-channel VCF-TIA array realized in a standard 0.18- $\mu \text{m}$ CMOS process demonstrate 76.3-dB $\Omega $ transimpedance gain, 6.3-pA/sqrt(Hz) average noise current spectral density, less than −33-dB crosstalk between channels, and 29.8-mW power dissipation per channel from a single 1.8-V supply. Automatic gain control is also equipped to extend input dynamic range for near-range detection. Hence, the proposed linear-mode optical sensor clearly detects the reflected optical pulses from the target of 5% reflection rate within the range of 0.5–25 m.
46 citations
TL;DR: Though the image signal-to-noise was not altered, the ease of photography for most images was improved and digital dynamic-range compression is a practical technique to aid in surface-coil MRI studies.
Abstract: The large dynamic range in signal intensity present in MR surface-coil images makes proper windowing and photography difficult. By removing the low-spatial frequency information caused by variations in surface-coil field intensity from the high-spatial frequency information containing the image data, a considerable compression of this dynamic range of signal intensity is possible. To accomplish this, a technique was implemented on a digital computer for use with MR surface-coil image data. The compression was done as a postprocessing option after the patient scan had been completed and therefore did not alter actual scan times. Although the image signal-to-noise was not altered, the ease of photography for most images was improved. Thus, digital dynamic-range compression is a practical technique to aid in surface-coil MRI studies.
46 citations
TL;DR: A 1.3-megapixel CMOS image sensor with digital correlated double sampling and 17-b column-parallel two-stage folding-integration/cyclic analog-to-digital converters (ADCs) is developed and is demonstrated at the video rate operation of 30 Hz by the new architecture of the proposed ADCs and the high-performance peripheral logic parts using low-voltage differential signaling circuit.
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-.
45 citations
16 Feb 1994
TL;DR: The authors show that including the transimpedance photodiode amplifier in a delta-sigma modulated loop with digitally-corrected trilevel quantizers/DACs leads to lower thermal noise.
Abstract: Transducers such as photodiodes produce signal currents in the 1 pA to 1 /spl mu/A range. To achieve a six-decade dynamic range, thermal noise currents at the system input must be minimized. The authors show that including the transimpedance photodiode amplifier in a delta-sigma modulated loop with digitally-corrected trilevel quantizers/DACs leads to lower thermal noise. The characteristics of the modulator are summarized. >
45 citations