from an Arecibo transmission. In their pulsed mode some of the military radars can achieve power densities closer to what Arecibo can generate, but only for extremely short periods. This would be inadequate for most demonstration purposes, but might still be high enough to take useful scientific data. In addition, use of military facilities for a peaceful power transmission experiment might have positive public relations effects that would make their use more attractive. Orbital Considerations Totally aside from the issue of what ground facilities could be used, it is worth remembering that there are two parts to any beamed power demonstration: a transmitter and a receiver. For this particular demonstration, the receiver is a small spacecraft. To determine the characteristics and cost of the receiving spacecraft, it is necessary to take a look at the impact of various orbit choices on the mission. On first consideration, one would desire either a geostationary or low equatorial orbit. A GEO orbit would overcome the tracking problem, while a lower equatorial orbit would pass within Arecibo’s arc several times a day. Figure 3 shows the problem with this concept. Arecibo can only see objects along the equator if they are over 70.000 km away. Note that BMEWS and COBRA DANE radars would also be unable to follow equatorial orbits due to both latitude and facing. Since we can't have an equatorial orbit, and several potentially useful military radars are located at high latitudes, a relatively high inclination orbit would seem to be in order.
RkJQdWJsaXNoZXIy MTU5NjU0Mg==