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Updated: Jun 20, 2026
06:14
Simulating Imaging of Large Scale Radio Arrays on the Lunar Surface
Published on: July 30, 2020
Summary
New large-index-step arrays use leaky modes for stable, high-power operation. Mode discrimination is key, offering advantages over evanescently coupled designs for continuous-wave applications.
Area of Science:
- Optics and Photonics
- Semiconductor Devices
- Waveguide Arrays
Background:
- Traditional evanescently coupled arrays face limitations at high power levels.
- Understanding mode selection is crucial for stable device performance.
Purpose of the Study:
- To elucidate the mode-selection mechanism in large-index-step index-guided arrays.
- To demonstrate stable fundamental mode operation at high power.
Main Methods:
- Theoretical analysis of mode characteristics in index-guided arrays.
- Numerical calculations of mode discrimination based on coupling region width.
Main Results:
- Identified a new class of "leaky modes" for operation.
- Demonstrated significant mode discrimination, favoring the fundamental mode.
- Mode discrimination is sensitive to coupling region width, not drive current.
Conclusions:
- Large-index-step arrays offer stable, high-power operation via leaky modes.
- These arrays present an alternative to evanescently coupled designs.
- Potential for stable continuous-wave (cw) operation at high drive currents.
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