| 摘要 |
The present invention discloses a system and method for creating high resolution synthesized phase centre movement with minimal antenna elements. A plurality of antenna elements are, which are spatially distributed within a quarter wavelength of one another, are each connected to individual variable gain sections, such as radio frequency (RF) digital attenuators. A control means, such as a microprocessor, is configured to control the level of gain from each variable gain section, to that the gain of each anterma element can be individually modified. Varying the gain distribution between antenna elements of an antenna array has the effect of shifting the phase centre of the array. Thus, as gain is redistributed between antenna elements the phase centre of the array is displaced and a synthesized Doppler is induced upon the signal. Phase center panning is reciprocal; that is, varying the gain distribution between antenna elements in a transmit array or in a receive array will induce the same synthesized-Doppler effect upon the signal. By varying the gain distribution between antenna elements in a continuous predetermined manner a continuous predetermined phase center movement will be generated, which will be measured as a cyclic Doppler shift by an observing carrier-phase user receiver.
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