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Record 1,  Textual support,  English

Record number: 1, Textual support number: 1 CONT

In coherent Doppler lidar, heterodyning is achieved by mixing the backscattered radiation with light from a frequency-stable continuous-wave laser, i. e., the so-called local oscillator(LO).  4, record 1, English, - coherent%20Doppler%20lidar

Record 1,  Textual support,  French

Record 1,  Textual support,  Spanish

Record 2,  Textual support,  English

Record number: 2, Textual support number: 1 OBS

A highly stable local radio-frequency oscillator used for heterodyning signals to produce an intermediate frequency.  4, record 2, English, - stable%20local%20oscillator

Record 2,  Textual support,  French

Record number: 2, Textual support number: 1 OBS

L'abréviation anglaise «stalo» est couramment utilisée en français.  1, record 2, French, - oscillateur%20local%20stabilis%C3%A9

Record 2,  Textual support,  Spanish

Record 3,  Textual support,  English

Record number: 3, Textual support number: 1 DEF

The sum or difference frequency resulting from the heterodyning of two signals or, under some conditions, of more than two signals.  1, record 3, English, - beat%20note

Record 3,  Textual support,  French

Record 3,  Textual support,  Spanish

Record 4,  Textual support,  English

Record number: 4, Textual support number: 1 CONT

This process is similar to heterodyning where two discrete frequencies are mixed together to produce sum, difference and product frequencies from which an IF is selected.  2, record 4, English, - heterodyning

Record 4,  Textual support,  French

Record number: 4, Textual support number: 1 OBS

159  1, record 4, French, - changement%20de%20fr%C3%A9quence%20simple

Record 4,  Textual support,  Spanish

Record 5,  Textual support,  English

Record number: 5, Textual support number: 1 CONT

The term "heterodyning" refers [in this article] to the experiment in which the scattered light is mixed with a local oscillator, while "homodyning" refers to self-beating of the scattered light.  2, record 5, English, - heterodyning

Record number: 5, Textual support number: 2 CONT

Harmonic generation, optical mixing, heterodyning, and rectification.  3, record 5, English, - heterodyning

Record 5,  Textual support,  French

Record number: 5, Textual support number: 1 CONT

Une méthode de mesure des faibles variations des constantes élastiques dans les milieux transparents par hétérodynage optique en diffusion Brillouin stimulée a été mise au point et décrite [...]. Les fréquences des battements de la lumière diffusée par un cristal témoin avec celle diffusée par le cristal soumis à une contrainte extérieure conduisent aux variations de vitesse élastique [...]  1, record 5, French, - h%C3%A9t%C3%A9rodynage%20optique

Record 5,  Textual support,  Spanish

Record 6,  Textual support,  English

Record number: 6, Textual support number: 1 CONT

The laser(or lidar) velocimeter [lidar=light radar] operates in a fashion entirely analogous to that of the airborne Doppler weather radars likely soon to be available for detecting turbulence in storm cells. As with radars, the device detects air movements by observing the motion of particles suspended in the air and carried with it. The only significant difference is that a beam of coherent infrared radiation is used to scan ahead of the aircraft, instead of a beam(or series of pulses) of radio energy in the considerably longer-wavelength microwave band. The frequency of the back-scattered echoes or reflections undergoes Doppler shift detection by standard heterodyning techniques, which involve comparing the frequency of the reflected illumination with that of the original laser beam. Any reflecting object or material which has motion relative to the transmitter/receiver will cause a detectable shift in frequency, which can be isolated from the transmitter's own proper motion(over the ground) and thus yield a precise indication of the speed at which the air is moving several hundred metres in front of the aircraft. From this data, it is easy to compute what the air speed of the aircraft will be when it reaches that particular patch of air in a few seconds’ time [and hence detect possible turbulence ahead].  2, record 6, English, - laser%20velocimeter

Record 6,  Textual support,  French

Record number: 6, Textual support number: 1 CONT

Le principe de fonctionnement du vélocimètre à laser (ou lidar) est exactement le même que celui des radars météorologiques Doppler de bord, qui doivent être mis en service prochainement pour la détection des turbulences dans les systèmes d'orages.  1, record 6, French, - v%C3%A9locim%C3%A8tre%20%C3%A0%20laser

Record 6,  Textual support,  Spanish