Physics – Optics
Scientific paper
2007-05-23
Physics
Optics
34 pages, 7 figures
Scientific paper
10.1364/AO.46.004092
The performance of telescope systems working at microwave or visible/IR wavelengths is typically described in terms of different parameters according to the wavelength range. Most commercial ray tracing packages have been specifically designed for use with visible/IR systems and thus, though very flexible and sophisticated, do not provide the appropriate parameters to fully describe microwave antennas, and thus to compare with specifications. In this work we demonstrate that the Strehl ratio is equal to the phase efficiency when the apodization factor is taken into account. The phase efficiency is the most critical contribution to the aperture efficiency of an antenna, and the most difficult parameter to optimize during the telescope design. The equivalence between the Strehl ratio and the phase efficiency gives the designer/user of the telescope the opportunity to use the faster commercial ray-tracing software to optimize the design. We also discuss the results of several tests performed to check the validity of this relationship that we carried out using a ray-tracing software, ZEMAX and a full Physical Optics software, GRASP9.3, applied to three different telescope designs that span a factor of $\simeq 10 in terms of D/lambda. The maximum measured discrepancy between phase efficiency and Strehl ratio varies between $\simeq 0.4 and 1.9 up to an offset angle of >40 beams, depending on the optical configuration, but it is always less than 0.5 where the Strehl ratio is >0.95.
Bolli Pietro
Olmi Luca
No associations
LandOfFree
Ray-tracing and physical-optics analysis of the aperture efficiency in a radio telescope does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Ray-tracing and physical-optics analysis of the aperture efficiency in a radio telescope, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Ray-tracing and physical-optics analysis of the aperture efficiency in a radio telescope will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-401969