Study Of Linear Feed Dual Reflector Antenna For Spatial Power Combining

Under the situation of electronic countermeasure, high-power electromagnetic wave,which is radiating to the free space, is usually needed. Circuit combining and spatial powercombining are the two main kinds in power combining. For the transmission loss and circuitarea increased nonlinear when the number of device increased, the number of device thatcircuit combining can combine is limited. The technique of spatial power combining utilizeslarge-diameter beams or wave-guide modes to directly couple with active devices. Thecombining efficiency of spatial power combing is high and almost irrelevant to the number ofthe device.Array feed reflector antenna is a important aspect of spatial power combining. If the linearE-horn array, whose elements are all fed by same amplitude and phase, is used as the feed ofthe parabolic antenna, the power combing efficiency is not high. In order to solve themismatch between the linear E-horn array and parabolic antenna, two novel linear horn arrayfeed dual reflector antennas are proposed, which are based on classical Cassegrain antennaand Gregorian antenna. With the design of suitable vice-reflector, the cylindrical wave whichis radiated from the linear horn array, is changed to the spherical wave after the reflection ofthe vice-reflector. So the linear horn array and the vice-reflector are equivalent to point sourcefeed, which can illuminate the main parabolic reflector effectively. Simulation results usingmultilevel fast multipole method show that the proposals mentioned both solve the mismatcheffectively, and the efficiency of the antennas both reaches50%.The parameters, such as the cone angle that cut the vice-reflector or the main-reflector, theangle of the illumination from the array to the vice-reflector, the curve lines forming thevice-reflector, are taken into discussion. The results are helpful in the designation of the linearhorn array feed dual reflector antenna.Another way to design the vice face of the dual reflector antenna is presented. First aproper form of function is used to represent the vice face model, and then the parameters ofthe function are optimized to get the objective vice face.As the units of the linear horn array are all excited in same amplitude and phase, only themechanical scanning of the antenna is analyzed. It is including vice-reflector andmain-reflector mechanical scanning.