Communications, Radar & Electronic Warfare (201.. - Index of

Communications Electronic Warfare309EOS (DF#1 ) •__ •• ,,/>----_ ... .-..... -.. -... . :>. /-'--./.,:-::..._--- ./DF#1 ' ... --;:-.---:;-'. _;l"- (OF.l ; OF#2}• E06,,?..-.. '//.. -........ -.. ..... ................... ..fi .... ...E01 (DF#3)--...• ••,.............. .Figure 17.24Overlapping OF coverage illuwation.where more than one DF provides coverage. The mid grey means that two (any two) ofthe DFs provide coverage and the darkest area is covered by all three. As usual, thedesign is performed in the same way as described in Section 12.14, which discussesradio optimisation, with the link budget being calculated for the target transmission allthe way into the DF receiver.The enemy transmissions are shown numbered as EOI-E06. Also shown arewhich DFs pick up the transmissions. Of these, E06 is not detected by any of theDFs since it outside the coverage area. Both EOl and E05 are picked up by only oneDF each. This prevents localisation because there is only one bearing to work with.E02 and E04 are each picked up by two DFs. This does allow localisation but withsignificantly less accuracy than if three DFs provided the localisation data. OnlyE03 is picked up by all three DF sensors and this provides the best localisationopportunity.This illustrates one of the main DF baseline considerations; we want to providecoverage by at least three DFs over the widest possible region of the search area. This isdistinct from the aspirations in detection network design where we want to provide themaximum coverage without overlap.