scholarly journals Signal-to-noise optimization and evaluation of a home-made visible diode-array spectrophotometer

1993 ◽  
Vol 15 (6) ◽  
pp. 227-232 ◽  
Author(s):  
Ivo M. Raimundo, Jr. ◽  
Celio Pasquini
Keyword(s):  
Dynamic Range ◽  
Signal To Noise Ratio ◽  
Low Cost ◽  
Optical Design ◽  
Signal To Noise ◽  
Noise Optimization ◽  
Instrument Control ◽  
Automatic Methods ◽  
Photodiode Array ◽  
Variable Integration

This paper describes a simple low-cost multichannel visible spectrophotometer built with an RL512G EGG-Reticon photodiode array. A symmetric Czerny-Turner optical design was employed; instrument control was via a single-board microcomputer based on the 8085 Intel microprocessor. Spectral intensity data are stored in the single-board's RAM and then transferred to an IBM-AT 3865X compatible microcomputer through a RS-232C interface. This external microcomputer processes the data to recover transmittance, absorbance or relative intensity of the spectra. The signal-to-noise ratio and dynamic range were improved by using variable integration times, which increase during the same scan; and by the use of either weighted or unweighted sliding average of consecutive diodes. The instrument is suitable for automatic methods requiring quasi-simultaneous multiwavelength detections, such as multivariative calibration and flow-injection gradient scan techniques.

An Over 120dB Dynamic Range Linear Response Single Exposure CMOS Image Sensor with Two-stage Lateral Overflow Integration Trench Capacitors

2020 ◽  
Vol 2020 (7) ◽  
pp. 143-1-143-6 ◽  
Author(s):  
Yasuyuki Fujihara ◽  
Maasa Murata ◽  
Shota Nakayama ◽  
Rihito Kuroda ◽  
Shigetoshi Sugawa
Keyword(s):  
Linear Response ◽  
Dynamic Range ◽  
Signal To Noise Ratio ◽  
Cmos Image Sensor ◽  
Image Sensor ◽  
Signal To Noise ◽  
Single Exposure ◽  
Two Stage ◽  
Noise Ratio ◽  
Maximum Signal

This paper presents a prototype linear response single exposure CMOS image sensor with two-stage lateral overflow integration trench capacitors (LOFITreCs) exhibiting over 120dB dynamic range with 11.4Me- full well capacity (FWC) and maximum signal-to-noise ratio (SNR) of 70dB. The measured SNR at all switching points were over 35dB thanks to the proposed two-stage LOFITreCs.

BANDWIDTH OF THE RECEIVER OF DIGITAL SIGNALS WITH A LARGE DYNAMIC RANGE

2021 ◽  
Vol 0 (11) ◽  
Author(s):  
A. E. Denisov ◽  
◽  
D. P. Danilaev ◽  
G. I. Il'in ◽  
◽  
...  
Keyword(s):  
Communication Channel ◽  
Dynamic Range ◽  
Signal To Noise Ratio ◽  
Digital Signals ◽  
Resolution Time ◽  
Large Dynamic Range ◽  
Signal To Noise ◽  
Radio Engineering ◽  
Channel Parameters ◽  
Analytical Relations

The analysis of the connection between the bandwidth and the dynamic range, the signal-to-noise ratio, the resolution time and the bandwidth is carried out. The problems are solved by deriving analytical dependencies based on the Shannon – Hartley theorem, as well as the well-known postulates of the theory of radio engineering circuits and signals. The study of analytical relations allows us to identify restrictions on the choice of communication channel parameters.

Internally Modulated Chirped Pulse Based Direct Detection Type φ-OTDR System with High Signal-to-Noise Ratio and Low Cost

2019 ◽  
Vol 46 (8) ◽  
pp. 0806003
Author(s):  
李鲁川 Luchuan Li ◽  
卢斌 Bin Lu ◽  
王校 Xiao Wang ◽  
梁嘉靖 Jiajing Liang ◽  
郑汉荣 Hanrong Zheng ◽  
...  
Keyword(s):  
Direct Detection ◽  
Signal To Noise Ratio ◽  
Low Cost ◽  
High Signal ◽  
Signal To Noise ◽  
Chirped Pulse ◽  
Noise Ratio

A Motorized Microdrive for Recording of Neural Ensembles in Awake Behaving Rats

2005 ◽  
Vol 127 (6) ◽  
pp. 1035-1040 ◽  
Author(s):  
R. Venkateswaran ◽  
Chris Boldt ◽  
J. Parthasarathy ◽  
B. Ziaie ◽  
A. G. Erdman ◽  
...  
Keyword(s):  
Signal To Noise Ratio ◽  
Low Cost ◽  
Dynamic Control ◽  
Experimental Paradigm ◽  
Signal To Noise ◽  
Implanted Electrodes ◽  
Neural Ensembles ◽  
Dc Motors ◽  
Cell Electrode ◽  
Scientific Advances

The recording of neural ensembles in awake, behaving rats has been an extremely successful experimental paradigm, providing demonstrable scientific advances. Dynamic control of the position of the implanted electrodes is of key importance as mobile electrodes provide a better signal-to-noise ratio and a better cell/electrode yield than nonmobile electrodes. Here we describe the use of low cost, soon to be commercially available dc motors to successfully control the depth of electrodes. The prototype designed is approximately 30mm in diameter and 50mm in length and weighed about 30gms. This paper presents the results of linear displacements of electrodes achievable with this motorized microdrive.

scholarly journals A Signal to Noise Optimization Algorithm for Speckle Interferometry Applications

2008 ◽  
Vol 13-14 ◽  
pp. 29-38
Author(s):  
J. Molimard ◽  
R. Cordero ◽  
A. Vautrin
Keyword(s):  
Rigid Body ◽  
Coupling Effect ◽  
Signal To Noise Ratio ◽  
Practical Interest ◽  
Speckle Interferometry ◽  
Rigid Body Motion ◽  
Body Motion ◽  
Signal To Noise ◽  
Full Field ◽  
Noise Optimization

Optical Full Field Techniques (OFFT) are more and more utilized by mechanical laboratories. Among these methods, interferometry techniques (mainly composed of Speckle/Grating Interferometry or Speckle/Grating Shearography) are more difficult to use in a mechanical lab context, because of their sensitivity to external vibrations (except shearography), and because of the global lack of optical culture of mechanical engineers. Speckle-based methods are of great practical interest for the users, but their signal to noise ratio (SNR) is affected by the rigid body motion of the specimen. Here, the speckle decorrelation is minimized at local scale directly using the SNR. First, a shearography experiment is modeled to characterize the recorrelation procedure for a rigid body motion, a constant strain map and finally a high degree of localization. The mean noise level is found to be 6 times higher than a fully-correlated phase map for a 1 pixel speckle size. Last, a first application to a single-ply fabric composite lamina is shown. Resulting strain maps are of high quality with a very low spatial resolution (4 pixels). The local bending / global tension coupling effect is clearly put in evidence.

scholarly journals Estimation and Correction of Sampling Time Offsets in Tiadcs using Optimization Algorithm

2020 ◽  
Vol 9 (4) ◽  
pp. 1217-1222
Keyword(s):  
Optimization Algorithm ◽  
High Frequency ◽  
Performance Metrics ◽  
Dynamic Range ◽  
Signal To Noise Ratio ◽  
Sampling Time ◽  
Signal To Noise ◽  
High Sampling ◽  
Noise Ratio ◽  
Estimation And Correction

In recent communication technologies, very high sampling rates are required for rf signals particularly for signals coming under ultra high frequency (UHF), super high frequency (SHF) and extremely high frequency (EHF) ranges. The applications include global positioning system (GPS), satellite communication, radar, radio astronomy, 5G mobile phones etc. Such high sampling rates can be accomplished with time-interleaved analog to digital converters (TIADCs). However, sampling time offsets existing in TIADCs produce non-uniform samples. This poses a drawback in the reconstruction of the signal. The current paper addresses this drawback and offers a solution for improved signal reconstruction by estimation and correction of the offsets. A modified differential evolution (MDE) algorithm, which is an optimization algorithm, is used for estimating the sampling time offsets and the estimated offsets are used for correction. The estimation algorithm is implemented on an FPGA board and correction is implemented using MATLAB. The power consumption of FPGA for implementation is 57mW. IO utilization is 27% for 4-channel TIADCs and 13% for 2-channel TIADCs. The algorithm estimated the sampling time offsets precisely. For estimation the algorithm uses a sinusoidal signal as a test signal. Correction is performed with sinusoidal and speech signals as inputs for TIADCs. Performance metrics used for evaluating the algorithm are SNR (signal to noise ratio), SNDR (signal to noise and distortion ratio), SFDR (spurious-free dynamic range) and PSNR (peak signal to noise ratio). A noteworthy improvement is observed in the above mentioned parameters. Results are compared with the existing state of the art algorithms and superiority of the proposed algorithm is verified.

scholarly journals Comparing current noise in biological and solid-state nanopores

2019 ◽  
Author(s):  
A. Fragasso ◽  
S. Schmid ◽  
C. Dekker
Keyword(s):  
Solid State ◽  
Single Molecule ◽  
Signal To Noise Ratio ◽  
Low Cost ◽  
Ionic Current ◽  
Low Noise ◽  
Signal To Noise ◽  
Experimental Conditions ◽  
High Frequencies ◽  
Noise Ratio

AbstractNanopores bear great potential as single-molecule tools for bioanalytical sensing and sequencing, due to their exceptional sensing capabilities, high-throughput, and low cost. The detection principle relies on detecting small differences in the ionic current as biomolecules traverse the nanopore. A major bottleneck for the further progress of this technology is the noise that is present in the ionic current recordings, because it limits the signal-to-noise ratio and thereby the effective time resolution of the experiment. Here, we review the main types of noise at low and high frequencies and discuss the underlying physics. Moreover, we compare biological and solid-state nanopores in terms of the signal-to-noise ratio (SNR), the important figure of merit, by measuring free translocations of a short ssDNA through a selected set of nanopores under typical experimental conditions. We find that SiNx solid-state nanopores provide the highest SNR, due to the large currents at which they can be operated and the relatively low noise at high frequencies. However, the real game-changer for many applications is a controlled slowdown of the translocation speed, which for MspA was shown to increase the SNR >160-fold. Finally, we discuss practical approaches for lowering the noise for optimal experimental performance and further development of the nanopore technology.

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