ARRAY ANTENNA SYSTEM TO BE INSTALLED ON SPACEPORT

摘要

PURPOSE:To realize an antenna system with a high gain and narrow beam width and whose radiant direction can be stabilized by setting the difference of length of a longest optical fiber and a shortest optical fiber out of plural optical fibers whose one end are connected to an optical signal distributor and other ends to each photoelectric signal switching device less than a pre scribed value. CONSTITUTION:The one ends of managing length optical fibers 16a-16e are connected to the optical signal distributor 14, and the other ends to photodiode modules 17a-17e. Also, the difference (L1-L2) of the length L1 of the longest managing length optical fiber 19b and the length L2 of the shortest managing length optical fiber 19c is set as (L1-L2)=750000/(nXdelta)m for the full width at half maximum delta f[Hz] of the frequency spectrum of a transmission signal source 4 and the refractive index (n) of the managing length optical fibers 16a-16e. The photodiode modules 17a-17e are connected to phase shifters 18a-18e. The phase shifters 18a-18e are connected to the feed parts of plane element antennas 11a-11e, respectively.