Accession Number : AD0688415

Title :   Continuously Visible Satellite Constellations

Descriptive Note : Final rept.

Corporate Author : NAVAL RESEARCH LAB WASHINGTON DC

Personal Author(s) : Easton, R L ; Brescia, R

PDF Url : AD0688415

Report Date : 30 Apr 1969

Pagination or Media Count : 14

Abstract : The results of this study show that a minimum of six satellites is required in a controlled-orbit constellation to have at least one satellite continuously visible from all points on the earth's surface. The study also examined the number of required satellites for different heights and various minimum elevation angles. To have two satellites visible at all times it is sufficient to double the number required for a single-satellite condition; to have three satellites simultaneously visible it is sufficient to triple the number required for a single-satellite condition. A constellation that is to have at least one visible satellite every place on the earth results in approximately twice the coverage of the earth's surface, but to date no easy method has been found for assuming that this duplication can be used to reduce the number required for having two, or three, mutually visible satellites at one time.

Descriptors :   *NAVAL OPERATIONS, *NAVIGATION SATELLITES, ALIGNMENT, ALTITUDE, NAVAL RESEARCH, NETWORKS, ORBITS, STATISTICAL ANALYSIS, SYNCHRONOUS SATELLITES

Subject Categories : Active & Passive Radar Detection & Equipment
      Spacecraft Trajectories and Reentry
      Ground Support Sys & Facil For Space Vehicles

Distribution Statement : APPROVED FOR PUBLIC RELEASE