Compact Rydberg atom-based LF transmitter

Cornerstone Research Group Inc. (CRG) proposes to develop a low frequency transmitter for active sensing of ionospheric and magnetospheric plasma density structure. CRG will leverage its experience with the compact Rydberg-atom based VLF transmitter for submarine to air communication. Active sensing with injection of ELF/VLF (300Hz -30kHz) frequency band electromagnetic waves into the Earthrsquo;s magnetosphere have played an important role in discovering and elucidating wave-particle interactions in near-Earth space. For example, Siple Station VLF injection experiments were very successful in producing observations of non-linear growth and triggering whistler mode waves. Today, however, electromagnetic sounding of ionospheric and magnetospheric plasma density structure at low frequencies relies on passive sensing, i.e., using either naturally occurring radiation or using transmitters of opportunity such as global navigation satellite system or ground-based transmissions. The reason for that lies in in the significant engineering challenges of efficiently radiating in the low frequency bands. Rydberg atom-based technology overcomes many of these challenges and makes it feasible to construct a compact VLF transmitter which could be installed on a space platform. During Phase I, CRG will demonstrate design of such a transmitter adhering to the SWAP constraints associated with the space applications.