Demonstration of the COBRA Teardrop Concept Using Two Smallsats in 8-Hour Elliptic Orbits

Space Resource America Corporation is engaged in developing new concepts for communications satellite systems that will avoid interference with any of the Geostationary satellites and can provide a significant increase in global capacity compared with that of the GEO ring. Additionally, since all satellites in such a system are flying in formation, they will not interfere with each other. The company has filed for a series of patents on the orbital arrays, or constellations, that appear to hold the most promise in satisfying both commercial and government requirements. Each of the three active arcs of a single 8-hour satellite has a ground trace that resembles a coiled COBRA, and the orbits were so named. The acronym-like name COBRA was later amplified to “Communications Orbiting Broadband Repeating Arrays”. One of these arrays employs six 8-hour period leaning elliptical orbit satellites describing three continuous closed paths in the Northern Hemisphere. Ground antennas follow these satellites as their active arcs describe a repeating teardrop-shaped closed path in the sky. The tracking rate is very slowaveraging about 10 degrees/hour. It is possible to demonstrate all of the features of this array, however, with only two satellites. SRA is planning such a demonstration using two smallsats with a limited broadband communications payload. The communications payload will operate at Ku band or higher. The repeating ground tracks of this planned satellite duo will allow for an 8-hour demonstration daily in each of three Northern Hemisphere regions. The three teardrop shaped loops are separated in longitude by 120 degrees. One teardrop is centered upon the United States, the second on Japan and eastern China, and the third on central Europe. Conveniently, each regional demonstration will begin and end at the same local time of day. The use of smallsats for this demonstration is very desirable, in order to hold down costs of both satellites and launch vehicles. The design lifetime of the satellites will be approximately six months to a year, with the satellites being de-orbited at the appropriate time. Draim, John E. 15 Annual/USU Conference on Small Satellites