A signal and system design for a lunar experiment system

A communication system design for a Lunar Exploration Program is developed. The system is designed to fulfill the requirement to transmit data from astronaut-implanted experiments back to Earth for at least one year after the astronaut(s) have departed. It is assumed that the ground station for this system will be of the type employed in the Jet Propulsion Laboratory Deep Space Network. A brief description of this ground station, including basic functional block diagrams and key parameters, is presented. A comparison is made of the three basic pulse code modulation formats. Percent data power in a given bandwidth for each code is determined. Maximum bit rate capability of the receiver, both as a function of bandwidth and received power level, is then established. Consideration is given to synchronization properties of the codes. The treatment includes consideration of the antenna characteristic required to provide continuous coverage of the earth for at least one year. Bit rate performance as a function of effective radiated power is also presented. The design decisions are summarized and a proposed system is presented. Test data is provided in support of the design technique.