PROJECT ECHO - FM DEMODULATORS WITH NEGATIVE FEEDBACK
Abstract
Open-ended Terms: Echo Project. The primary experimental objective of Project Echo was the transmission of radio communications between points on the earth by reflection from the balloon satellite. Owing to the large path losses from transmitter to receiver via the satellite, a wide-band freq ency modulation technique was used in which bandwidth was traded for signal-to-noise ratio. The FM receiving demodulators are described. Negative feedback applied to the local oscillator reduces the FM mo ulation index in the receiver IF amplifiers, resulting in threshold performance superior to that of conventional FM receivers. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1961
- Accession Number
- AD0264029
Entities
People
- Clyde L. Ruthroff
Organizations
- National Aeronautics and Space Administration