A downconverter is a downconverter that, used in television display, converts a high-definition television picture in HDTV to a picture for standard television. Corresponding devices are called HD downconverters.
If a standard display is offered an HDTV signal that it cannot display, then the corresponding signal must be converted to the standard format via an HD downconverter. High-definition downconverters are characterized by the slightest image distortion in the form of blurring, aliasing or image noise. They convert videos with a wide range of frame rates and aspect ratios.
Insatellite communications, downconverters convert a higher signal frequency to a lower one. For example, signals from the C-band, Ku-band or Ka-band are downconverted to frequencies of 70 MHz, 140 MHz or to the L-band with frequencies between 950 MHz and 1,450 MHz.