scholarly journals ANALYSIS AND TRADE-OFF STUDY OF SIGNAL-TO-NOISE RATIO DEPENDENT DESIGN PARAMETERS OF SATELLITE PASSIVE ELECTRO-OPTICAL REMOTE SENSORS

2007 ◽  
Vol 12 (ASAT CONFERENCE) ◽  
pp. 1-13
Author(s):  
Fawzy Hasan ◽  
Mahmoud Mahmoud ◽  
Ibrahim Abdel Dayem ◽  
Adel El-Nozahy ◽  
Mohamed Abdel Hady
Keyword(s):  
Signal To Noise Ratio ◽  
Design Parameters ◽  
Signal To Noise ◽  
Trade Off ◽  
Remote Sensors ◽  
Ratio Dependent ◽  
Noise Ratio

scholarly journals Design optimisation of permanently installed monitoring system for polycrystalline materials

2020 ◽  
pp. 147592172095019
Author(s):  
Yuan Liu ◽  
Peter B. Nagy ◽  
Peter Cawley
Keyword(s):  
Surface Area ◽  
Monitoring System ◽  
Signal To Noise Ratio ◽  
Coarse Grained ◽  
Polycrystalline Materials ◽  
Depth Range ◽  
Bulk Wave ◽  
Signal To Noise ◽  
Trade Off ◽  
Noise Ratio

This article presents a design procedure for structural health monitoring systems based on bulk wave ultrasonic sensors for structures fabricated from polycrystalline materials. When designing a monitoring system, maximum coverage per transducer is a general requirement in order for the system to be economic. For coarse-grained polycrystalline materials, monitoring is often made challenging by low signal-to-noise ratios caused by grain scattering. Therefore, when designing a monitoring system for these materials, in addition to the economic requirement, it needs to be ensured that an adequate signal-to-noise ratio can be obtained throughout the monitoring volume. This typically introduces a trade-off between volume coverage per transducer and sensitivity that must be investigated. In this article, this trade-off is studied and a methodology using signal-to-noise maps is presented to design the system, that is, choose the optimal transducer parameters and placement. First, a combined analytical and numerical approach is used to generate a signal-to-noise map. Then, the influence of various factors on signal-to-noise ratio is investigated. Finally, two representative examples, with different criteria, are given to illustrate the methodology. In one example, the full surface area of the testpiece is covered with transducers and the optimum gives the deepest coverage. The other one aims to achieve the minimum fractional surface area that has to be covered with transducers to monitor a narrow depth range far from the surface, which has a potential application in weld monitoring. Results show that the optimum is likely to be at much lower frequency than typically used in inspection, as tracking signals with time gives sensitivity gains. Experiments were carried out to illustrate that higher volume coverage can be obtained at lower frequencies.

Super-resolution methods in MRI: Can they improve the trade-off between resolution, signal-to-noise ratio, and acquisition time?

2012 ◽  
Vol 68 (6) ◽  
pp. 1983-1993 ◽  
Author(s):  
Esben Plenge ◽  
Dirk H. J. Poot ◽  
Monique Bernsen ◽  
Gyula Kotek ◽  
Gavin Houston ◽  
...  
Keyword(s):  
Signal To Noise Ratio ◽  
Super Resolution ◽  
Acquisition Time ◽  
Signal To Noise ◽  
Trade Off ◽  
Noise Ratio

scholarly journals Parameter Simulation and Design of an Airborne Hyperspectral Imaging LiDAR System

2021 ◽  
Vol 13 (24) ◽  
pp. 5123
Author(s):  
Liyong Qian ◽  
Decheng Wu ◽  
Dong Liu ◽  
Shalei Song ◽  
Shuo Shi ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Spectral Density ◽  
Hyperspectral Imaging ◽  
Optical Fibers ◽  
Signal To Noise Ratio ◽  
Design Parameters ◽  
Signal To Noise ◽  
Lidar System ◽  
Power Spectral ◽  
Noise Ratio

With continuous technological development, the future development trend of LiDAR in the field of remote sensing and mapping is to obtain the elevation and spectral information of ground targets simultaneously. Airborne hyperspectral imaging LiDAR inherits the advantages of active and passive remote sensing detection. This paper presents a simulation method to determine the design parameters of an airborne hyperspectral imaging LiDAR system. In accordance with the hyperspectral imaging LiDAR equation and optical design principles, the atmospheric transmission model and the reflectance spectrum of specific ground targets are utilized. The design parameters and laser emission spectrum of the hyperspectral LiDAR system are considered, and the signal-to-noise ratio of the system is obtained through simulation. Without considering the effect of detector gain and electronic amplification on the signal-to-noise ratio, three optical fibers are coupled into a detection channel, and the power spectral density emitted by the supercontinuum laser is simulated by assuming that the signal-to-noise ratio is equal to 1. The power spectral density emitted by the laser must not be less than 15 mW/nm in the shortwave direction. During the simulation process, the design parameters of the hyperspectral LiDAR system are preliminarily demonstrated, and the feasibility of the hyperspectral imaging LiDAR system design is theoretically guaranteed in combination with the design requirements of the supercontinuum laser. The spectral resolution of a single optical fiber of the hyperspectral LiDAR system is set to 2.5 nm. In the actual prototype system, multiple optical fibers can be coupled into a detection channel in accordance with application needs to further improve the signal-to-noise ratio of hyperspectral LiDAR system detection.

scholarly journals A New Method to Estimate Peak Signal to Noise Ratio for Least Significant Bit Modification Audio Steganography

2022 ◽  
Vol 30 (1) ◽  
pp. 497-511
Author(s):  
Muhammad Harith Noor Azam ◽  
Farida Ridzuan ◽  
M Norazizi Sham Mohd Sayuti
Keyword(s):  
Signal To Noise Ratio ◽  
High Capacity ◽  
Least Significant Bit ◽  
Early Assessment ◽  
Signal To Noise ◽  
Trade Off ◽  
Audio Steganography ◽  
Early Evaluation ◽  
Noise Ratio ◽  
Different Levels

Audio steganography is implemented based on three main features: capacity, robustness, and imperceptibility, but simultaneously implementing them is still a challenge. Embedding data at the Least Significant Bit (LSB) of the audio sample is one of the most implemented audio steganography methods because the method will give high capacity and imperceptibility. However, LSB has the lowest robustness among all common methods in audio steganography. To cater to this problem, researchers increased the depth of the embedding level from fourth to sixth and eighth LSB level to improve its robustness feature. However, consequently, the imperceptibility feature, which is commonly measured by Peak Signal to Noise Ratio (PSNR), is reduced due to the trade-off between imperceptibility and robustness. Currently, the lack of study on the estimation of the PSNR for audio steganography has caused the early assessment of the imperceptibility-robustness trade-off difficult. Therefore, a method to estimate PSNR, known as PSNR Estimator (PE), is introduced to enable early evaluation of imperceptibility feature for each stego-file produced by the audio steganography, which is important for the utilisation of embedding. The proposed PE estimates the PSNR based on the pattern collected from the embedment at different levels. From the evaluation, the proposed method has 99.9% of accuracy in estimating PSNR values at different levels. In comparison with the Mazdak Method, the proposed method performs better in all situations. In conclusion, the proposed PE can be used as a reference for embedding and further reducing the calculation complexity in finding the feasible value to minimise the trade-off between robustness and imperceptibility.

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