Spatial filtering design considerations for a line scanning sensor.
The performance of an airborne laser terrain mapper, which collects slant range and reflectance data simultaneously, is determined in part by the spatial filtering effects of the finite size of the illuminating beam. An analysis of the distortion of the relative range measurement (terrain profile) due to both spatial filtering and detector noise effects is presented. The distortion due to spatial filtering is shown to increase with the laser modulation frequency, while the rms errors due to receiver noise decrease with frequency. Thus, the performance of the sensor can be optimized for specific expected terrain characteristics by properly choosing the size of the system's optics (which determines beam size) and the laser modulation frequency. Numerical examples are presented to illustrate the approach.
Robinson
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Strautman
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