Comparison of the crossed and the Gregorian Mizuguchi-Dragone for wide-field millimeter-wave astronomy.
We compare the geometric and physical-optics performance of two configurations of offset dual-reflector antennas that obey the Mizuguchi-Dragone condition. The traditional Gregorian configuration is compared with the larger crossed configuration. These configurations are candidates for experiments that measure the polarization of the cosmic microwave background. Particular attention is given to wide-field performance and polarization fidelity. Both a ray tracer and a physical optics simulation package are used to conclude that the crossed configuration has a larger diffraction-limited field of view, but within this limit both configurations have roughly the same instrumental polarization and both show excellent cross-polarization levels, with the crossed configuration showing approximately 10 dB better performance.
Tran
Huan
H
University of California, Berkley, California 94720, USA. huantran@bolo.berkeley.edu
Lee
Adrian
A
Hanany
Shaul
S
Milligan
Michael
M
Renbarger
Tom
T