A 1296 MHz Earth-Moon-Earth Communication System

Abstract

The task of designing, building and characterizing an Earth–Moon–Earth (EME) communication system in the 1296 MHz amateur radio band has been successfully accomplished. Using the radar equation and thermal noise theory, in conjunction with measured and estimated system parameters, the lunar echo signal to noise ratio (SNR) has been estimated at 5.4+1.2 −1.6 dB (2) in a 100 Hz bandwidth. The results of empirical long-term averaged SNR measurements are within the boundaries of this estimate, thus adding to its validity. Additionally, measurements of the libration-induced Doppler spread of the lunar echoes show good agreement with theoretical predictions. Further experiments should be conducted however, in order to asses the repeatability of the results. Improvements to the system and measurement methods should also be considered. The report focuses on both theory and practice and apart from the above, additional attention is given to the topic of low noise figure (NF) measurements due to the systemic importance of the LNA NF parameter.