Long-Range Compact Economical Lidar for Wind Profiling

Beyond Photonics is developing a high-performance wind measurement lidar system, which we have named the Wind Beyond lidar, that will enable reliable wind measurements to 20+ km near-horizontal ranges in the atmospheric boundary layer.nbsp; Use of in-band-pumped Er:YAG laser crystals for the Wind Beyond transmitter allows for much higher pulse energies than are possible with low-cost all-fiber transmitter architectures.nbsp; The proposed Wind Beyond lidar will operate at 7.5 mJ pulse energy and 1 kHz PRF, resulting in a transmitter figure of merit that is about 10x larger than typical commercially available lidar systems based on Er:fiber transmitters.nbsp; The significantly lower transmitter PRF than used in most commercial Er:fiber-based lidar systems (typically 10+ kHz) eliminates range ambiguity problems and lowers signal acquisition and processing requirements.nbsp; The proposed lidar operates at a very-high-transmission wavelength near 1645 nm which also supports the ability to measure winds at long distances.nbsp; Even with its significantly higher pulse energy, the proposed lidar is a Class 1M eye-safe system.nbsp; Although the focus of the near-term development is for wind measurement applications, operation near 1645 nm also allows for potential application to atmospheric methane and water vapor concentration measurements in the future. The Wind Beyond lidar transmitter enables: Measurement to near-horizontal-path ranges that are 2-3 times larger (exact factor depending on atmospheric visibility) than possible with the lower performance lidars at equivalent update rates ndash; i.e., coverage of much larger measurement volume at a given update rate.nbsp;nbsp; Measurements to the same range as the lower performance lidars but with approximately 100x the measurement update rate ndash; i.e., coverage of a fixed measurement volume 100x faster. A combination of very small discrete optical components and precision fabrication methods provides an innovation which allows for economical manufacturing.