L.M. Vdovin - Ph.D. (Eng.), Division Head, JSC «POLYOT Research and Production Company», V.R. Milov - Dr.Sc. (Eng.), Professor, Head of Department Nizhny Novgorod State Technical University n.a. R.E. Alek-seev T.I. Goriacheva - Ph.D. (Eng.), Associate Professor, Nizhny Novgorod State Technical University n.a. R.E. Alekseev D.V. Milov - Post-graduate Student, Nizhny Novgorod State Technical University n.a. R.E. Alekseev

When the possibility exists for control by ground station of multiple access protocol to aviation VDL-4 channel, this essentially decrease time of into network entry, allows fast detection and resolve of random access collision. In Manual for digital data link VDL-4 (Doc.9816) general principles of multiple TDMA + FDMA access protocol to VDL-4 channel in controlled mode by ground station given. Also VDL-4 Frequencies Management Scenario 1 given, for different area of Air Space, every of which characterizes by their own parameters: message flow intensity (λgiv) from Aircraft (AC), packet possible transfer delay d0pos, PIAC (Peaking Instantaneous Aircraft Count) into the area air space. Control algorithm Implementation of multiple access to channel protocol demand of guaranteeing specified proof of given in Doc.9816 data link VDL-4 system characteristic for concrete the area air space, in order to packet transfer delay d0 ≤ d0pos for λgiv. Knowledge of d0 dependences: from number (М) of AC, which used one channel, from λgiv, from predicted parameter of p-persistence (р1) of packet retransmission after random access collision detection, from random access clots number in frame (с) allows to predicted this system parameter (d0) using magnitudes of М, λgiv, р1, с and to guarantee its possible magnitudes non more, than d0pos, by control algorithm of access protocol to VDL-4 channel, providing at that maximum number of AC, which used one channel (Мmax). Statistical analysis method and analysis of dependent of protocol system parameter (d0) from М, λgiv, р1, с parameters are performed. As a result of this analysis, adaptive control algorithm of this access protocol to VDL-4 channel proposed.

 

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