John H. Glenn Research Center, Cleveland, Ohio
This report presents the design, construction, and test results of a novel multitone, multi-band, high-frequency synthesizer for application in a space-borne (including a CubeSat) beacon transmitter for radio wave atmospheric propagation studies. The beacon transmitter synthesizer design can be tailored to operate in those frequency bands of interest for future space-to-Earth data links, e.g., Q-band (37 to 42 GHz) and E-band (71 to 76 GHz).
The synthesizer consists of a high-frequency comb generator or harmonic generator, which puts out a broad range of evenly spaced harmonic frequencies that has been observed to be tunable over a wide frequency range. These harmonics are filtered to select a set of frequencies that is representative of a desired beacon source. The harmonics can then be amplified to the power levels needed for radio wave atmospheric propagation studies. The harmonics that are amplified are transmitted from space to Earth as beacon signals. By measuring the relative strength and phase of these signals on Earth, one can estimate the attenuation and dispersion due to atmospheric effects.
This work was done by Rainee N. Simons and Edwin G. Wintucky of Glenn Research Center.
Inquiries concerning rights for the commercial use of this invention should be addressed to NASA Glenn Research Center, Innovative Partnerships Office, Attn: Steven Fedor, Mail Stop 4–8, 21000 Brookpark Road, Cleveland, Ohio 44135. Refer to LEW-19122-1.