MTSAT took over all the major meteorological functions of Geostationary Meteorological Satellite 5 (GMS-5) including the function to disseminate imagery data. Since the start of MTSAT operation, two imagery dissemination services, LRIT and HRIT, have been performed.
Low Rate Information Transmission (LRIT) is an imagery dissemination service for Small-scale Data Utilization Stations (SDUS). LRIT specification is defined by the Coordination Group for Meteorological Satellites (CGMS).
LRIT imagery enables users to utilize the data in a wider range of applications extracting quantitative meteorological parameters.
Further technical specifications of LRIT are described in 'JMA LRIT Mission Specific Implementation' and 'CGMS 03 LRIT/HRIT Global Specification'.
High Rate Information Transmission (HRIT) is an imagery dissemination service for Medium-scale Data Utilization Stations (MDUS). HRIT specification is defined by CGMS as well as LRIT one.
Since images disseminated by HRIT are produced with minimal conversion from observed data, the center point of the images are the same as the position of an observation satellite, which is around 145°E for MTSAT-2 and around 140°E for MTSAT-1R.
The specifications of HRIT are described in 'JMA HRIT Mission Specific Implementation' and 'CGMS 03 LRIT/HRIT Global Specification'.
Satellite Program Division, Japan Meteorological Agency
E-mail: metsat AT met.kishou.go.jp