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  2. Doppler effect - Wikipedia

    en.wikipedia.org/wiki/Doppler_effect

    [1] [2] [3] The Doppler effect is named after the physicist Christian Doppler, who described the phenomenon in 1842. A common example of Doppler shift is the change of pitch heard when a vehicle sounding a horn approaches and recedes from an observer. Compared to the emitted frequency, the received frequency is higher during the approach ...

  3. Ives–Stilwell experiment - Wikipedia

    en.wikipedia.org/wiki/Ives–Stilwell_experiment

    Initial attempts to measure the second order transverse Doppler effect in canal rays completely failed. For example, Stark's 1906 measurements showed systematic errors ten times the predicted effect. [5] The maximum speed achievable in early gas-discharge tubes was about 0.005 c, which implied a transverse Doppler shift of only about 1.25×10 ...

  4. Relativistic Doppler effect - Wikipedia

    en.wikipedia.org/wiki/Relativistic_Doppler_effect

    Doppler shift with source moving at an arbitrary angle with respect to the line between source and receiver. The analysis used in section Relativistic longitudinal Doppler effect can be extended in a straightforward fashion to calculate the Doppler shift for the case where the inertial motions of the source and receiver are at any specified angle.

  5. Doppler radar - Wikipedia

    en.wikipedia.org/wiki/Doppler_radar

    Doppler Effect: Change of wavelength and frequency caused by motion of the source. The formula for radar Doppler shift is the same as that for reflection of light by a moving mirror. [3] There is no need to invoke Albert Einstein's theory of special relativity, because all observations are made in the same frame of reference. [4]

  6. Doppler spectroscopy - Wikipedia

    en.wikipedia.org/wiki/Doppler_spectroscopy

    Doppler spectroscopy (also known as the radial-velocity method, or colloquially, the wobble method) is an indirect method for finding extrasolar planets and brown dwarfs from radial-velocity measurements via observation of Doppler shifts in the spectrum of the planet's parent star. As of November 2022, about 19.5% of known extrasolar planets ...

  7. Satellite geodesy - Wikipedia

    en.wikipedia.org/wiki/Satellite_geodesy

    Doppler positioning involves recording the Doppler shift of a radio signal of stable frequency emitted from a satellite as the satellite approaches and recedes from the observer. The observed frequency depends on the radial velocity of the satellite relative to the observer, which is constrained by orbital mechanics .

  8. Satellite geolocation - Wikipedia

    en.wikipedia.org/wiki/Satellite_geolocation

    The frequency differences observed are due to different Doppler shift resulting from relative satellite motion and differences in the translation frequencies of the two satellite channels. Channel translation frequencies and downlink Doppler shift and delay can be calibrated out of the measurements by observing transmitters of known location ...

  9. Doppler radio direction finding - Wikipedia

    en.wikipedia.org/wiki/Doppler_radio_direction...

    The magnitude of the shift is a function of the wavelength of the signal and the angular velocity of the antenna: S = ⁠ r W / λ ⁠ Where S is the Doppler shift in frequency (Hz), r is the radius of the circle, W is the angular velocity in radians per second, λ is the target wavelength and c is the speed of light in meters per second. [13]