Sentinel-3 SRAL
change note: 2018-07-10 13:47:19.0 [mmorahan] Insert Concept add broader relation (Sentinel-3 SRAL [7b6e3162-1314-4441-b33a-e2b68ae85bcd,367819] - Radar Altimeters [92ddaaca-40b2-4936-bc1a-28cc5743e8b8,347963]);
change note: 2019-03-26 17:11:21.0 [sritz] insert WeightedRelation (id: null related concept uuid: 41163801-6aac-43e5-aed7-9f52613a6a73 relationship type: null relationship value: null generated by: null);
change note: 2018-07-10 13:49:44.0 [mmorahan] insert AltLabel (id: null category: primary text: Sentinel-3 SAR Radar Altimeter language code: en); insert Definition (id: null text: SRAL is a redundant dual-frequency (C-band + Ku-band) nadir-looking altimeter instrument, and the core instrument of the topographic payload. The overall objectives are to provide altimetric data (basic measurements of surface heights, sea wave heights and sea wind speed) relative to a precise reference frame. SRAL has a strong heritage of the instrument techniques implemented for the Poseidon-3 altimeter on Jason-2 (launch June 20, 2008), SIRAL (SAR Interferometer Radar Altimeter) on CryoSat-2 (launch April 8, 2010), and AltiKa (Altimeter in Ka-band) on the SARAL mission of ISRO and CNES (launch 2012). The SRAL instrument is being developed at TAS (Thales Alenia Space) of Toulouse, France. The SRAL radar uses a linearly frequency-modulated pulse (chirp) and the pulse compression is carried out on-board by means of the deramp technique. The main frequency used for surface height measurements is the Ku-band (13.575 GHz, bandwidth=350 MHz), whereas the C-band frequency (5.41 GHz, bandwidth=320 MHz) is used for the ionospheric corrections. The frequency plan is compliant with the ITU (International Telecommunication Union) regulations. A 50 ms pulse duration for both frequencies has been sized as a trade-off result between a high BT product and the timing constraints of the burst pattern of the SAR mode. The SRAL altimeter instrument is made of one nadir looking antenna subsystem which is externally mounted on the satellite +Zs panel and central electronic chains composed each of a DPU (Digital Processing Unit) and a RFU (Radio Frequency Unit). The central electronic chains are mounted inside the satellite on the -YS panel and are treated according to a cold redundancy scheme. The SRAL instrument includes measurement modes, calibration modes and support modes. The measurement modes are composed of two ra…
change note: 2019-02-22 14:45:03.0 [mmorahan] insert WeightedRelation (id: null related concept uuid: 5449d87b-5573-450f-8acb-2fdfeab3c8ce relationship type: null relationship value: null generated by: null);
change note: 2019-03-26 17:11:44.0 [sritz] update WeightedRelation (Instrument-Sensor); update WeightedRelation (1);
type: Concept
definition: SRAL is a redundant dual-frequency (C-band + Ku-band) nadir-looking altimeter instrument, and the core instrument of the topographic payload. The overall objectives are to provide altimetric data (basic measurements of surface heights, sea wave heights and sea wind speed) relative to a precise reference frame. SRAL has a strong heritage of the instrument techniques implemented for the Poseidon-3 altimeter on Jason-2 (launch June 20, 2008), SIRAL (SAR Interferometer Radar Altimeter) on CryoSat-2 (launch April 8, 2010), and AltiKa (Altimeter in Ka-band) on the SARAL mission of ISRO and CNES (launch 2012). The SRAL instrument is being developed at TAS (Thales Alenia Space) of Toulouse, France. The SRAL radar uses a linearly frequency-modulated pulse (chirp) and the pulse compression is carried out on-board by means of the deramp technique. The main frequency used for surface height measurements is the Ku-band (13.575 GHz, bandwidth=350 MHz), whereas the C-band frequency (5.41 GHz, bandwidth=320 MHz) is used for the ionospheric corrections. The frequency plan is compliant with the ITU (International Telecommunication Union) regulations. A 50 ms pulse duration for both frequencies has been sized as a trade-off result between a high BT product and the timing constraints of the burst pattern of the SAR mode. The SRAL altimeter instrument is made of one nadir looking antenna subsystem which is externally mounted on the satellite +Zs panel and central electronic chains composed each of a DPU (Digital Processing Unit) and a RFU (Radio Frequency Unit). The central electronic chains are mounted inside the satellite on the -YS panel and are treated according to a cold redundancy scheme. The SRAL instrument includes measurement modes, calibration modes and support modes. The measurement modes are composed of two radar modes associated to two tracking modes. The two radar modes are the following: • LRM (Low Resolution Mode). It refers to the conventional altimeter pulse-limited re…
in scheme: instruments

Radar Altimeters
type: Concept