A Coherent Detecting System of THz for Earth Environment Observation
- Paper ID
5419
- author
- company
Xi'an Institute of Space Radio Technology;
- country
China
- year
2009
- abstract
THz technology is a cross field of electronics and optics. The performance of THz, different from other electromagnetic radiation, makes it prospective in biology, space physics and astronomy, chemical analysis, telecommunication and radar etc. Before middle 1980s, EM wave at 1mm-100μm band was called THz gap, because no high energy, high efficiency, stable, low cost THz source had been found. As ultra-fast laser technology fast developing, THz impulse generation and application have found their way in the last decade. In this paper, a coherent detecting system with cryostat of THz is introduced. The detecting system was made for the earth observation will be well used for collecting information about the Earth and its environment. As we all know, there are many important spectrum lines between 0.48THz-0.64THz. And the detector has a SIS mixer which makes it just work at the frequency band. For example, the CO molecule has a absorption line in spectral band of sun at 0.5THz. So the detecting system can observe the content of CO around the earth by detecting the CO’s spectrum. Meanwhile the system also has a cryosat using liquid nitrogen, which makes it work at a high sensitivity.