| 摘要 |
<p>A radio direction finding station for locating lightening strikes has three vertical antenna loops (10, 11, 12) in an equiangular trigonal arrangement. The vertical loops are positioned to minimise magnetic coupling between them and with a fourth horizontal loop (14). Filters (25-28) pass only signals from the loops with frequencies below about 2.6 kHz to eliminate most horizontally polarised components of the received radio waves. The signal from the horizontal loop represents any residual horizontally polarised component and is used in a central control station to correct for residual polarisation error in the measured bearings.</p> |
