Abstract: A fire control system that includes an array of photodiode elements. For each element of the photodiode array, there is a specific optical path in the atmosphere leading from the laser to a target and back from the target to the element. Accordingly, each element of the detector array can be regarded as if illuminated by a distinct light source. For short time periods (in the range of tens to hundreds of milliseconds) the shape or spatial distribution of the refractive-index irregularities does not significantly change, and the irregularities drift with the atmospheric wind. By measuring the signal fluctuations by any element of the photodiode array, it is possible to compute the crosswind velocity. By comparing signal fluctuations patterns of two or more elements it is possible to define the wind direction and to determine the turbulence strength value.

Abstract: A fire control system that includes an array of photodiode elements. For each element of the photodiode array, there is a specific optical path in the atmosphere leading from the laser to a target and back from the target to the element. Accordingly, each element of the detector array can be regarded as if illuminated by a distinct light source. For short time periods (in the range of tens to hundreds of milliseconds) the shape or spatial distribution of the refractive-index irregularities does not significantly change, and the irregularities drift with the atmospheric wind. By measuring the signal fluctuations by any element of the photodiode array, it is possible to compute the crosswind velocity. By comparing signal fluctuations patterns of two or more elements it is possible to define the wind direction and to determine the turbulence strength value.

Abstract: A radiation transmission optical fiber having a core and cladding for spectroscopic monitoring includes a transmission portion and a sensor portion; the transmission portion has a continuous core portion and a continuous cladding over the core portion; the sensor portion has the cladding removed from one side of the fiber and the core portion exposed from the same side leaving the continuous cladding intact over the opposite side of the core portion of the sensor.