CFOSAT is a mini satellite, composed of a platform supplied by CNSA, and a payload. The payload is composed of two instruments:
- a wave-scatterometer spectrometer (Surface Waves Investigation and Monitoring instrument: SWIM) supplied by CNES,
- a wind-scatterometer (SCAT) supplied by CNSA.
Both are Ku-band radars (13.2 to 13.6 GHz) scanning around the vertical axis. SWIM is a 6-beam radar at small incidence (0 to 10°), SCAT is a rotating fan-beam radar with larger incidence angles (18~50°). This combination of incidence angles is necessary to measure the wind vector (from large incidence) and wave properties (from small incidence). The interest for the combination of the two payloads is evident since surface wind is the energy source which creates the surface waves; the space and time evolution of these surface waves, is dependent on both local and remote wind conditions. The combination of the two instruments will help to separate the different effects governing the evolution of the wave field.