Recirculating Advanced Coupled-cavity Etalon Receiver (RACER)
sensors
Recirculating Advanced Coupled-cavity Etalon Receiver (RACER) (GSC-TOPS-145)
This device mitigates one of the fundamental limitations for LiDAR architectures pulse repetition frequency (PRF)
Overview
This technology is a spectrally-resolved receiver that enables higher pulse repetition frequency (PRF) and thus lower laser pulse energy LiDAR instruments to tackle the long standing problem of having the ability to separate very closely spaced wavelengths with minimal loss. For earth, in order to have an accurate reading, the repetition rate is limited to 10 KHz corresponding to a 100 s round-trip through the atmosphere.
The Technology
Advanced Coupled-cavity Etalon (ACE) significantly improves both in-band transmission and out-of-band rejection. In some cases, 12% more light is transmitted inside the passband and >3x more light is rejected outside the passband. Incorporating ACE into the recirculating etalon receiver (RER) improves performance significantly. ACE increases the wavelength resolution and enables closer channel spacing resulting in a very efficient, high resolution spectrometer. RACER has both high resolution and a high photon efficiency which allows flexibility for trading different combinations of reduced cross-talk and closer channel spacing.
Benefits
- Filters the noise and separates different laser wavelengths
- Design flexibility
- High resolution with minimal loss
Applications
- Meteorology
- Mapping/Altimetry
- Medicine
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