Development and Testing of HF Wire-Grid Lens Antenna. Volume Iii

摘要

The report describes the results of a series of measurements made on the FAA multi-beam Wire-Grid Lens HF Antenna (located at Molokai, Hawaii) during the summer of 1967 to determine its message traffic-handling capacity when equipped with optimized feeds. Error rate measurements were made of signals received on the lens operating simultaneously in the simplex mode and the angle-diversity mode in which a signal is simultaneously received on a pair of beams pointing in slightly different azimuth directions. The tests were carried out by TRG under the overall supervision of FAA and AFCS representatives. The median binary error rate for the simplex mode of operation was found to be 0.00033, while the median binary error rate for the angle-diversity mode of operation was found to be 0.000027 which represents a 12 to 1 improvement. Optimized feed binary error rate measurements were also made on circuit 100 wpm radioteletypewriter signals alternately received on the lens and a station rhombic for comparison with the error rates. The essential test conditions of the previous tests were duplicated. The simplex binary error rate ratio of the lens to a rhombic was found to be 2.5 to 1 favoring the rhombic. (Author)