| 摘要 |
An active transmit phased array antenna system for generating multiple independent simultaneous antenna beams to illuminate desired regions while not illuminating other regions. The size shape of the regions is a function of the size and number of elements populating the array and the number of beams is a function of the number of beam forming networks feeding the array. All the elements of the array are operated at the same amplitude level and beam shapes and directions are determined by the phase settings. The active transmit phased array antenna includes a plurality of antenna elements (10,12,14) disposed in a hexiform configuration. Each antenna element is identical and includes a radiating horn (10) capable of radiating in each of two orthogonal polarizations. The horn is fed by a multi-pole bandpass filter (12) whose function is to pass energy in the desired band and reject energy at other frequencies. The filter means is coupled into an air dielectric cavity (14) mounted on substrate (36). The air dielectric cavity contains highly efficient monolithic amplifiers which excite orthogonal microwave energy in a push-pull configuration by probes (18,20,30,32) in combination with amplifiers (22,24,26,28) placed such that they drive the cavity at relative positions 180 degrees apart. Phase shift means (48) and attenuator means (46) in the substrate are connected to the amplifiers in the cavity to determine beam and direction and for maintaining the signal amplitudes from each of the antenna elements at an equal level. <IMAGE> <IMAGE> |
