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Active-tracking scaling laws using the noise-equivalent angle due to speckle
Summary
This study introduces validated scaling laws for speckle noise in active-tracking systems. It provides engineers with accurate, closed-form expressions to predict performance limitations, improving system design.
Area of Science:
- Optical Engineering
- System Engineering
- Signal Processing
Background:
- Speckle noise is a known limitation in active-tracking system performance.
- Existing models lack quantitative scaling laws and experimental validation.
Purpose of the Study:
- To formulate closed-form expressions for speckle-induced noise-equivalent angle.
- To validate these expressions through wave-optics simulations.
Main Methods:
- Developed analytical expressions for speckle noise.
- Analyzed both well-resolved and unresolved cases for circular and square apertures.
- Compared analytical results with numerical simulations.
Main Results:
- Achieved excellent agreement between analytical predictions and simulation results.
- Identified a track-error limitation of (1/3)λ/D, where λ/D is the aperture diffraction angle.
- Established validated scaling laws for speckle in active tracking.
Conclusions:
- The formulated expressions provide accurate predictions of speckle limitations.
- Validated scaling laws are now available for system engineers.
- This work bridges the gap in understanding and quantifying speckle effects on active-tracking performance.
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