SINR improvement using Firefly Algorithm (FA) for Linear Constrained Minimum Variance (LCMV) beamforming technique

2015 ◽  
Author(s):  
Camellia Doroody ◽  
Tiong Sieh Kiong ◽  
Soodabeh Darzi
Keyword(s):  
Firefly Algorithm ◽  
Minimum Variance ◽  
Beamforming Technique

Accurate diffraction imaging for detecting small-scale geologic discontinuities

Geophysics ◽  
2018 ◽  
Vol 83 (5) ◽  
pp. S447-S457 ◽  
Author(s):  
Peng Lin ◽  
Suping Peng ◽  
Jingtao Zhao ◽  
Xiaoqin Cui ◽  
Wenfeng Du
Keyword(s):  
Signal To Noise Ratio ◽  
Migration Velocity ◽  
Minimum Variance ◽  
Seismic Interpretation ◽  
Small Scale ◽  
Imaging Method ◽  
Velocity Analysis ◽  
Diffraction Imaging ◽  
Correlation Properties ◽  
Beamforming Technique

Seismic diffractions contain valuable information regarding small-scale inhomogeneities or discontinuities, and therefore they can be used for seismic interpretation in the exploitation of hydrocarbon reservoirs. Velocity analysis is a necessary step for accurate imaging of these diffractions. A new method for diffraction velocity analysis and imaging is proposed that uses an improved adaptive minimum variance beamforming technique. This method incorporates the minimum variance, coherence factor, and correlation properties to improve the signal-to-noise ratio and enhance correlations. Our method can make seismic diffractions become better focused in semblance panels, allowing for the optimal migration velocity for diffractions to be accurately picked. Synthetic and field examples demonstrate that the migration velocity for the diffractions can differ from that for the reflections. The results suggest that the diffraction velocity analysis and imaging method is feasible for accurately locating and identifying small-scale discontinuities, which leads to the possibility of using this approach for practical application and seismic interpretation.

scholarly journals Beamforming of Joint Polarization-Space Matched Filtering for Conformal Array

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Lutao Liu ◽  
Yilin Jiang ◽  
Liangtian Wan ◽  
Zuoxi Tian
Keyword(s):  
Energy Loss ◽  
Data Model ◽  
Signal To Noise Ratio ◽  
Minimum Variance ◽  
Matched Filtering ◽  
Conformal Array ◽  
Linearly Constrained ◽  
Polarization Sensitive Array ◽  
Array Beamforming ◽  
Beamforming Technique

Due to the polarization mismatch of the antenna, the received signal suffers from energy loss. The conventional beamforming algorithms could not be applied to the conformal array because of the varying curvature. In order to overcome the energy loss of the received signal, a novel joint polarization-space matched filtering algorithm for cylindrical conformal array is proposed. First, the snapshot data model of the conformal polarization sensitive array is analyzed. Second, the analytical expression of polarization sensitive array beamforming is derived. Linearly constrained minimum variance (LCMV) beamforming technique is facilitated for the cylindrical conformal array. Third, the idea of joint polarization-space matched filtering is presented, and the principle of joint polarization-space matched filtering is discussed in detail. Theoretical analysis and computer simulation results verify that the conformal polarization sensitive array is more robust than the ordinary conformal array. The proposed algorithm can improve the performance when signal and interference are too close. It can enhance the signal-to-noise ratio (SNR) by adjusting the polarization of the elements of the conformal array, which matches the polarization of the incident signal.

Fuzzy multi-objective location and routing problem

2020 ◽  
Vol 39 (3) ◽  
pp. 3259-3273
Author(s):  
Nasser Shahsavari-Pour ◽  
Najmeh Bahram-Pour ◽  
Mojde Kazemi
Keyword(s):  
Firefly Algorithm ◽  
High Reliability ◽  
Research Area ◽  
Nsga Ii ◽  
Location Routing Problem ◽  
Routing Problem ◽  
Location Allocation ◽  
Multi Objective ◽  
Location Routing ◽  
The Cost

The location-routing problem is a research area that simultaneously solves location-allocation and vehicle routing issues. It is critical to delivering emergency goods to customers with high reliability. In this paper, reliability in location and routing problems was considered as the probability of failure in depots, vehicles, and routs. The problem has two objectives, minimizing the cost and maximizing the reliability, the latter expressed by minimizing the expected cost of failure. First, a mathematical model of the problem was presented and due to its NP-hard nature, it was solved by a meta-heuristic approach using a NSGA-II algorithm and a discrete multi-objective firefly algorithm. The efficiency of these algorithms was studied through a complete set of examples and it was found that the multi-objective discrete firefly algorithm has a better Diversification Metric (DM) index; the Mean Ideal Distance (MID) and Spacing Metric (SM) indexes are only suitable for small to medium problems, losing their effectiveness for big problems.

Sign in / Sign up

Export Citation Format

Share Document