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Updated: Sep 20, 2026

Continuous-Wave Propagation Channel-Sounding Measurement System - Testing, Verification, and Measurements
Published on: June 25, 2021
Dual-channel heterodyne measurements of atmospheric phase fluctuations
Kevin D Ridley1, Eric Jakeman, David Bryce
1QinetiQ, Room PB-115, St. Andrews Road, Malvern, Worcestershire WR14 3PS, UK. kdridley@qinetiq.com
Abstract:
A dual-channel fiber-coupled laser heterodyne system operating at a 1.55-microm wavelength is used to investigate phase fluctuations induced on a laser beam by propagation through turbulent air. Two receivers are used to characterize spatial and temporal variations produced by a turbulent layer of air in the laboratory. The system is also used for measurements through extended turbulence along an 80-m outdoor atmospheric path. Phase structure functions, power spectral densities, and cross correlations are presented.
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