Optical Instruments Concept for the Spanish Earth-observation Satellite
- Paper number
IAC-06-B1.3.09
- Author
Mr. Diego Rodríguez, SENER Ingeneria y Sistemas, S.A., Spain
- Coauthor
Mr. Carlos Miravet, SENER Ingeneria y Sistemas, S.A., Spain
- Coauthor
Mr. Emilio Vez, SENER Ingeneria y Sistemas, S.A., Spain
- Coauthor
Mr. Daniel Cocho, SENER Ingeneria y Sistemas, S.A., Spain
- Year
2006
- Abstract
Building on the experience gained in the nineties with the MINISAT and MINISOB programmes, SENER has participated since 2004 in two Spanish Government sponsored feasibility analyses for the development and commissioning of an Spanish National Earth-observation System. These studies have provided the technical and programmatic background for the recent announcement by the Spanish Minister of Transport, in the context of ESA’s Ministerial Council in Berlin, that such system shall enter into operation in 2010. A key area of responsibility for SENER in the mentioned feasibility analyses has been the payload of the satellite, and hence the optical instruments it is composed of. This paper provides information on the key aspects addressed while developing their concept. In the first study, the main instrument was expected to provide panchromatic and multi-spectral output channels. The required resolution was 1.5 m for the panchromatic instrument and 5 m for the multi-spectral one. The required swath, the same for both channels, was 20 Km. In response to them, SENER proposed a Korsch type telescope, with a focal length of 5780 mm and f number of 15.9. Both channels, multi-spectral and panchromatic, shared the same optics and field division was used to split them up. The focal plane array used divoli for detector combination. To complement the performance of the main instrument, and by this address the needs of a wider user community, two different secondary instrument configurations were as well analysed: a wide-field multi-spectral instrument, and a second one for stereoscopic imaging purposes. The most recent feasibility study, performed under the lead of the INTA and CDTI Spanish Institutions, considered a main instrument providing panchromatic and multi-spectral outputs. The resolution was 2,5 m for the panchromatic channel and 10 m for the multi-spectral one, and a swath of 30 Km. The architecture proposed was here a Ritchey-Chretien type telescope, with both channels sharing the optics. The optical system comprises two mirrors and three lenses with a focal length of 1740 mm and a 7.2 f number. Again, field division was used to split up panchromatic and multi-spectral channels and also to divide all four multi-spectral bands. An important conclusion reached in both studies, aside from the technical and programmatic feasibility of the system conceived, is that the Spanish industry has the capabilities required to undertake the responsibility of designing and integrating the proposed instruments, using a significant amount of locally manufactured components.
- Abstract document