Research on Parameters of the Trailing VLF Antenna Using Lumped-Mass Method

The verticality of Very Low Frequency (VLF) antenna is an important factor to decide the radiation intensity of airborne VLF communication system, and the close relation of which with the parameters of airplane, towed antenna, and drogue is an important issue. Considering from the aspect of system design, the flight speed and the drogue's mass are primary design variables whereas the bank angle constrained by airplane's maneuverability and cable's basic parameters decided by design requirement can be chosen initially. After modelling the trailing system with lumped-mass method, sensibility analyzation about relations of the verticality of antenna with the flight speed and the drogue's mass are carried on. The result is found that when a faster flight speed is chosen, it's not easy to gain enough verticality required, and leads to a conclusion that, flight speed dominates the verticality which should be decided seriously whereas the drogue's mass poses much less effect.