Fig. 9. Attitude profile of array to avoid specular reflection. The illumination loss is (1-cos i/i), or a maximum of about 0.003. This is insignificant compared to the 8% loss at the solstices resulting from the POP array orientation. 5. SPECULAR REFLECTION FROM ANTENNA The luminosity of the antenna due to specular reflection can be calculated in the same way as that of the solar array. In this case, if the reflective surface is a circle of diameter d - 1 km, the luminosity is As with the array, reflections can strike the earth only from nearly normal incidence on the antenna; area loss can therefore be neglected. Taking p = 0.95, we then have m = -14.1 if the other parameters are the same as in the preceding section. For efficient power transmission, the transmitting antenna must point toward the rectenna within about one minute of arc (1). Consequently, the antenna cannot be pointed so as to avoid reflections to the earth. Since the antenna will not, in general, point at the equator, the reflection can strike the earth at any point from which the SPS is visible. The relationship between the sun and the antenna is calculated as illustrated in Figure 10. If p is the longitude difference between satellite and rectenna and is the rectenna latitude,
RkJQdWJsaXNoZXIy MTU5NjU0Mg==