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Doppler shifts on high-frequency ground backscatter
Journal of Geophysical Research, 1969Frequency changes (Doppler shifts) of high-frequency radio waves propagated by a changing ionosphere can be observed and measured both for ground backscatter and for ‘point-to-point’ circuits. However, the relationships between ionospheric change and frequency shift are different in the two cases.
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Dynamic Doppler Frequency Shift Errors: Measurement, Characterization, and Compensation
IEEE Transactions on Instrumentation and Measurement, 2015Positioning calibration under dynamic conditions is becoming increasingly of interest for high precision fields, such as additive manufacturing and semiconductor lithography. Heterodyne interferometry is often used to calibrate a stage’s position because interferometry has a high dynamic range and direct traceability to the meter. When using heterodyne
Chen Wang, Jonathan D. Ellis
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Accurate Doppler Frequency Shift Estimation for any Satellite Orbit
2007 3rd International Conference on Recent Advances in Space Technologies, 2007One of the most important parameters in satellite communication links, particularly in low earth orbits (LEO) and elliptical orbits is Doppler frequency shift (DFS) and Doppler frequency rate (DFR) at communication channels. This paper analyzes Doppler frequency effects in various satellite orbits.
Shervin Amiri, Mohammad Mehdipour
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Laser Doppler velocimeter with variable optical frequency shift
Optics & Laser Technology, 1975Abstract An opto-electronic system that allows a stable accurate frequency shift, variable from 10 kHz to 50 MHz, to be introduced in a laser Doppler velocimeter (LDV) has been developed. The system combines a fixed optical-frequency shift obtained using a Bragg cell with an electronic shift which results from mixing the detector signal with a ...
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Using Frequency Hypsography to Deduce Doppler Frequency Shift and Phase Path
2007 International Conference on Microwave and Millimeter Wave Technology, 2007This paper presents a new method- using frequency hypsography to calculate Doppler shift and phase path. Formula deduced from this method can avoid some unbelievable factors that are produced from hypotheses on not only parameter of ionosphere but also model of electronic density distribution. And this formula can also explain "C" trace occurring on HF-
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Joint Estimation of Doppler Frequency Shift and Doppler Frequency Rate Based on Interpolation
Journal of Electronics & Information Technology, 2014Wei Jiang, Tian Le
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