Spectrum Database for Passive RA Receivers

The pilot study demonstrates the feasibility of a database approach for coordinating spectrum sharing between commercial and select RA bands. Most well-studied coexistence scenarios involve active incumbents, such as TV broadcast and radar signals, it is not feasible to develop sensing techniques for very faint radio emissions originating from cosmic sources and measured by RA telescopes. Spectrum allocation for RA is already done on a shared basis, with the RA service (RAS) given primary and secondary status in the allocation table, depending on the given band. To protect RAS from harmful in-band and adjacent-band interference, “coordination zones” have been established around major observation sites. However, these zones are conservative and result in missed opportunities for greater spectrum sharing. In this pilot study, we experiment with coexistence between passive RA receivers, on the one hand, and cellular (LTE and 5G sub-6 GHz) and WiFi transmissions on the other hand. The spectrum of interest for RA ranges from 2 MHz to 1 THz. However, for coexistence with cellular and WLAN systems, the immediate interest is in bands below 100 GHz, including 4.8-5 GHz band for continuum observations and various spectral lines between 1.37 GHz and 6.67 GHz (for substances such as hydrogen, methyladyne, methanol, etc.). Studies have shown that these bands can be adversely impacted by in-band as well as adjacent-band interference from WiFi and LTE sources. Under this pilot, we will implement the mini-database as a server-client system, where WiFi and LTE sources would seek permission from the database before accessing a given channel.