Spectrum Management for the Protection of Radio Astronomy

This proposal contains two areas of work, one in pursuing understanding of the impact from radio frequency interference (RFI) to cosmological experiments, especially RFI from spaceborne communication platforms such as satellites, and second to engage in spectrum management activities domestically and internationally. This two-year project focuses on the pursuit of coexistence between active and passive uses of the electromagnetic spectrum, including two main aspects. The first is a research thrust focused on measurements and analysis of impact of satellite downlinks to cosmic microwave background (CMB) astronomy, especially related to the single-dish CMB experiment, CLASS. The other main thrust is domestic and international spectrum management, to perform technical studies and to participate in work for the protection of radio astronomy, especially the CMB experiments. The technical study will include a pilot portion with a frequency generator to transmit signals at expected satellite downlink frequencies to observe the impact on the CLASS data pipeline. This pilot would be followed up by actual observations of satellites, utilizing telemetry to coordinate the observations. The international spectrum management work would focus on provision of technical expertise to three main study groups at the International Telecommunications Union: Study Group 7 (Science Services), Study Group 3 (Propagation Models), and Study Group 4 (Satellites). The PI would evaluate whether radio quiet zone rules could be amended to improve protection for radio astronomy (both in the U.S. and in Chile) and participate in the numerous international telecommunications meetings and conferences. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.