DOPPLER OPTICAL NAVIGATOR.
Abstract
The feasibility of novel laser techniques for Doppler optical navigation is discussed. The performance goal is the measurement of ground speed with 5 meters per second accuracy at a maximum altitude of 300 miles. Analysis of over-all performance of the Doppler optical navigation system leads to the conclusion that required transmitter power is considerably greater than the power available from currently available lasers. Developments which promise to reduce required transmitter power are described. The coherence gain afforded by amplitude modulation of the optical carrier wave is also analyzed. It is concluded that amplitude modulation not only simplifies the Doppler detection circuits but also increases the fractional intensity of the Doppler signal component. Measured stability of the He-Ne gas laser indicates that it is just about stable enough to provide a velocity measurement accuracy of 5 meters/second. Electronic circuits needed to evaluate the cuprous chloride direct amplitude modulator and to determine threshold detection levels are currently being fabricated. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 19, 1963
- Accession Number
- AD0420000
Entities
People
- C. W. Reno
- L. J. Nicastro
- W. J. Hannan
Organizations
- RTX