Panel setting from microwave holography by the method of successive projections

Microwave holography is an established technique for measuring the surface accuracy of large reflector antennas. It suffers from the disadvantage that the resulting surface error map is spatially bandlimited. Most large reflectors are constructed with panels, and misaligned panels give discontinuities in the surface error which cannot be resolved. This can lead to incorrect assessment of panel positions. Significant improvement can be obtained by recognizing at the outset that the reflector surface is approximated by a collection of individual rigid panels. The method of successive projections is used to incorporate information about the panel boundaries into the data reduction process. It has been applied successfully to measured data for a 26-m diameter radiotelescope, and an investigation of a large number of simulated experiments indicates that good results maybe achieved while minimizing measurement time.<
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