Range-gated laser and ICCD camera system for on-orbit detection of small space debris

摘要

A small, compact pulsed-laser and camera system for collecting data on small space debris can be put into orbit as a strap-on package on other research satellites. The system does not depend on sun glint for debris illumination. The laser could be diode-pumped Nd:YAG or Cr:LiSaAlF with high overall efficiency. It eventually could be e simple diode laser. It would operate in a pulse-rep mode of approximately 10 Hz, sampling truncated conical volumes out to $LS 1 km. With a 1 m primary optic, the system would see approximately 1 mm debris and larger out at approximately 800 m, and would see even smaller debris in the nearer field. The high gain of the ICCD camera enables use of lower laser energy (power). Filters eliminate most optical noise. Range-gating eliminates unwanted backscatter entering the camera. Data can be pre-processed on orbit, with only counts-per-bin (particle)-size data being transmitted. The initial lower-cost system would sample only in small diameter orbital `tubes.' Analysts would still make some assumptions about the homogeneity of distributions to develop a `picture' of the amount of small debris in orbit at various altitudes. Further trade-off studies are needed.