Performance analysis on MWIR and LWIR pushbroom imaging

Pushbroom imaging technology based on long linear array MWIR and LWIR detectors is one of the major technical solutions to achieve high spatial resolution and high temperature resolution satellite earth observation. With the development of long linear array infrared detectors, great attention has been given to this technology and it has been applied in some areas. The characteristics of MWIR and LWIR imaging were introduced. The current status of satellite pushbroom imaging based on long linear array MWIR and LWIR detectors was presented. Emphasis was put on the analysis of MWIR and LWIR imaging performances, including modulation transfer function (MTF), ground sampled distance (GSD), and noise equivalent temperature difference (NETD), according to their wavelength, radiation intensity of object with a temperature of 300 K, and parameters of optics and detectors. For objects with ambient temperature, if integration time was long enough, the MWIR pushbroom imaging can achieve higher spatial resolution and temperature resolution than LWIR under the same MTF. Some suggestions for improving MWIR and LWIR imaging performances were given according to the analysis result.