Acousto-optical correlation spectrometer for radio astronomy

The objective of this thesis is to develop and construct a wide-band, high-resolution, two-channel prototype acousto-optic correlation spectrometer (AOCS) to analyze signals received by the three-element millimeter-wave interferometer at Caltech's Owens Valley Radio Observatory (OVRO), which may be used to study the distribution of carbon monoxide and other molecules in galaxies. The proposed correlation spectrometer has the main advantage of large time-bandwidth products and hence of low cost per frequency channel. Thus, it is suitable for many scientific objectives that require both large bandwidth and high resolution, such as mapping the distribution and temperature of the interstellar gases of galactic sources and extragalactic sources or studying the atmospheric conditions of planets in the solar system. Phase switching has been used to reduce the zero level variation of this instrument, and is found to be more effective than other schemes used by the single dish acousto-optical spectrometers. Both the frequency resolution and the frequency coverage of this instrument can be changed easily, and give it a flexibility not attainable by the filter-bank spectrometers