heterodyne detection การใช้

• In heterodyne detection mode HgCdTe can be uncooled, although greater sensitivity is achieved by cooling.
• This improved signal-to-noise ratio makes absolute amplitude measurements feasible in heterodyne detection.
• Of special interest, this solves two common and vexing problems encountered in optical heterodyne detection.
• Continuous wave ( CW ) doppler radar detectors are basically heterodyne detection devices that compare transmitted and reflected beams.
• Both beams are then collected onto the photodetector where optical heterodyne detection is used to extract the Doppler signal.
• The objective of synthetic array heterodyne detection is to isolate regions of a large area detector surface into virtual pixels.
• Optical heterodyne detection has special temporal and spatial characteristics that pragmatically distinguish it from conventional Radio Frequency ( RF ) heterodyne detection.
• Optical heterodyne detection has special temporal and spatial characteristics that pragmatically distinguish it from conventional Radio Frequency ( RF ) heterodyne detection.
• While an old technique, key limiting issues were solved only as recently as 1994 with the invention of synthetic array heterodyne detection.
• Instead, a single-element optical detector can also act like diversity receiver via synthetic array heterodyne detection or Fourier transform heterodyne detection.
• Instead, a single-element optical detector can also act like diversity receiver via synthetic array heterodyne detection or Fourier transform heterodyne detection.
• A coherent imaging lidar uses synthetic array heterodyne detection to enable a staring single element receiver to act as though it were an imaging array.
• The radiation in question is most commonly either radio waves ( see superheterodyne receiver ) or light ( see Optical heterodyne detection or interferometry ).
• Optical heterodyne detection is used for coherent Doppler lidar measurements capable of detecting very weak light scattered in the atmosphere and monitoring wind speeds with high accuracy.
• Optical heterodyne detection is an essential technique used in high-accuracy measurements of the frequencies of optical sources, as well as in the stabilization of their frequencies.
• As a result, the mathematics of squaring the sum of two pure tones, normally invoked to explain RF heterodyne detection, is an oversimplified model of optical heterodyne detection.
• As a result, the mathematics of squaring the sum of two pure tones, normally invoked to explain RF heterodyne detection, is an oversimplified model of optical heterodyne detection.
• However, as noted above, scaling physical arrays to large element counts is challenging for heterodyne detection due to the oscillating or even multi-frequency nature of the output signal.
• Consequently, optical heterodyne detection is usually performed as interferometry where the LO and signal share a common origin, rather than, as in radio, a transmitter sending to a remote receiver.
• The reference beam is also sent to the photodetector where optical heterodyne detection produces an electrical signal proportional to the Doppler shift, by which the particle velocity component perpendicular to the plane of the beams can be determined.