illustrated by Fig. 5. However, the method recommended for constructing the slotted waveguide radiators provides ample room for cables to run from the slotted surface of the radiator to the magnetrons without having to penetrate the waveguides themselves. Further, the whole radiating module can be aligned in advance of its installation. The fact that only one frequency is involved is of great importance in simplifying the overall alignment procedure. The new design has advantages over the old in simplifying installations and maintenance of the radiating module. As suggested by Fig. 1, a rectenna subarray may be composed of many radiating modules of the design we have discussed. In the old design of Fig. I, all of the microwave drive is located in the microwave power generation zone through the use of waveguides because of the high drive level that had been previously assumed. It would be difficult to remove one of these radiating modules for servicing or repair without shutting down the entire subarray or even removing a substantial portion of it. By contrast, the new arrangement, with a low level drive for each radiating module that could be obtained from an isolating directional coupler, should make it possible to remove an individual radiating module with little difficulty and without impacting the operation of the balance of the subarray. In essence, the radiating module becomes a plug-in unit. ADAPTING THE DESIGN OF AN ELECTRONICALLY STEERABLE GROUND- BASED PHASED ARRAY TO THE REQUIREMENTS OF THE SUBARRAY IN THE SPS TRANSMITTING ANTENNA ARRAY The ground-based, electronically-steerable, phased array, designed for microwave- powered, high altitude balloons and for airplanes, as shown in Fig. 8, appears to have
RkJQdWJsaXNoZXIy MTU5NjU0Mg==