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Updated: Jul 10, 2026
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Simulating Imaging of Large Scale Radio Arrays on the Lunar Surface
Published on: July 30, 2020
Relativistic effects in earth-orbiting Doppler lidar return signals.
1Department of Physics, University of Colorado, Boulder, Colorado 80309-0390, USA. ashby@boulder.nist.gov
Summary
This study details high-order calculations for lidar frequency shifts, crucial for accurately measuring aerosol velocity from spacecraft. Precise wind velocity determination requires careful handling of relativistic effects and large velocity subtractions.
Area of Science:
- Space physics
- Atmospheric science
- Optical remote sensing
Background:
- Lidar (light detection and ranging) systems are used for remote sensing.
- Measuring aerosol velocity from spacecraft involves complex signal processing.
- Relativistic effects and large velocity subtractions can impact accuracy.
Purpose of the Study:
- To develop high-order calculations for lidar frequency shifts.
- To improve the accuracy of wind velocity measurements using lidar.
- To account for relativistic corrections in spacecraft-based remote sensing.
Main Methods:
- Calculated frequency shifts of side-ranging lidar signals to high order.
- Utilized an earth-centered inertial frame for calculations.
- Applied transformations to determine scatterer velocities relative to the ground.
Main Results:
- Frequency shifts were calculated considering spacecraft and Earth's rotation velocities.
- Identified that subtractions of large terms can lead to loss of significant digits.
- Highlighted the magnified effect of relativistic corrections on wind velocity determination.
Conclusions:
- High-order calculations are necessary for precise lidar measurements.
- Careful consideration of relativistic effects is vital for accurate wind velocity determination.
- The methodology provides a framework for improved remote sensing of atmospheric dynamics from space.
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