Figure 8 shows the cross section of the rectenna site using the cylinder parabolic reflectors. The primary radiator is placed on the back of the prop which supports the reflector. Figure 9 shows the cross section of the rectenna using the plane primary radiator, the power concentration D/Dj can be obtained in the same manner mentioned previously and is given by Figure 10 shows the power concentration D/Dj versus Da/f for the rectenna shown in figure 9. We can obtain the optimum value of Da which maximizes energy conversion efficiency. We arrange several CMS As lengthwise depending on as shown in figure 5. On the plane containing the focal line, we have a radiation pattern which is the same as the E-plane pattern of the CMSA shown in figure 4(a). Namely, the beam on the plane is very broad. On the plane perpendicular to the focal line, we have the radiation pattern which is determined by the reflector and the number of lengthwise CMSAs. The more CMSAs are arranged lengthwise, the broader the beam is, namely the allowance of the inclination angle of the SPS becomes large. The rectenna site is constructed on the equator in the SPS strawman model which will be mentioned later, and the elevation angle 0S is 90°. In this case, we can compose the rectenna as shown in figure 6. It is desired to place the CMSAs on the upper side of the primary radiator. The rectenna will be supported by props in the jungle in the SPS strawman model. The symmetrical structure shown in figure 11 is desirable because it is easy to keep the balance. Figure 12 shows the transmission factor of the sunlight as a function of D/f. The parameter is a diameter of the wires which compose the reflector. We see that more than 60% of the sunlight passes through the rectenna. Figures 13 through 16 show the rectenna . Figure 13 is a case where the diameter of the wires in 2.4 mm and the interval between them is 1.2 cm (about 1/10 of the wavelength). We can see that we do not have much radiation below the rectenna. In this case, about 62% of the sunlight passes through the rectenna. Figure 14 shows the case where the diameter is half of that shown in figure 13. We have higher radiation below the rectenna. A portion of the microwave power from the SPS passes through the rectenna. Figures 15 and 16 show the radiation patterns where the interval between the wires is 2.4 cm (about 1/5 of the wavelength). The interval is twice as wide as that shown in figures 13 and 14. A large portion of the microwave energy passes the rectenna when the interval between the wires is wide. From these results, it may be said
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