Simulation of Nonlinear Interference in Aircraft Systems Operating in Complex Electromagnetic Environment Created by Land-Based and Air-Based Wireless Systems Vladimir Mordachev 1 , Eugene Sinkevich 1 , Yuri Yatskevich 1 , Andrey Krachko 1 , Pavel Zaharov 2 , Xie Ma 3 1 EMC R&D Laboratory, Belarusian State University of Informatics and Radioelectronics, Minsk, Belarus, emc@bsuir.by 2 Aerosystema, Ltd., Minsk, Belarus, zaharov@aerosystem.by 3 China Electronics Technology Cyber Security Co., Ltd, 18081045600@163.com Abstract—Results of discrete nonlinear behavior simulation of aircraft wireless systems’ operation in complicated electromagnetic environment (EME) created by electromagnetic radiations of wireless systems allocated on the earth’s surface and in different surrounding airborne vehicles are presented. The simulation is performed with the use of technique of virtual testing area; this technique is based on implementation of geoinformation technologies for analysis of different scenarios of influence of unwanted signals on wireless systems of aircraft flying at low and medium altitudes. Results of simulation prove the presence of real danger of intermodulation interference in on- board VHF/UHF radio receivers of piloted aircraft in case of complicated EME at small and medium altitudes if unmanned aerial vehicles approach to the aircraft at distances which are acceptable from the viewpoint of air traffic control regulations. Keywords—EMC diagnostics, aircraft, nonlinear interference, UAV, behavior simulation. I. INTRODUCTION Intensive development and expansion of unmanned aerial vehicles (UAV) equipped with radar, data transfer, control, navigation, retransmitting, and other radio systems essentially changes the conditions of operation of the traditional piloted aircrafts at small and medium altitudes. The main reason of this is the complication of an electromagnetic environment (EME) at such altitudes and the increase of danger of interference to operation of airborne electronic complexes, including nonlinear distortions - intermodulation, cross-modulation, etc. As a result of simultaneous growth of terrestrial density of land-based radio systems of various services, the EME complicating at the indicated altitudes happens as at the expense of obvious growth of a total number of electromagnetic fields (EMFs) the level of which exceeds the susceptibility threshold of airborne receivers, and also at the expense of extension of their dynamic range. The last increases the danger of a nonlinear interferences to airborne receiver operation and is connected with the growth of number of potential air-based EMF sources and increasing the probability of their short-term inadvertent approaching to the aircraft at a distance at which the occurrence of interference caused by intermodulation and receiver’s spurious responses becomes possible. The objective of this paper is an estimation of danger of nonlinear interference in aircraft radio receivers operating in severe EME if the aircraft approaches to an UAV (or dirigible) and/or land-based EMF sources at a distance admissible from the point of view of the air traffic safety. II. MAIN PECULARITIES OF THE PROBLEM 1) High complexity of on-board systems of modern aircrafts (both piloted, and pilotless), containing a lot of different radio systems operating in a wide frequency range (from MF to SHF), that is the reason of the significant number and high levels of EMF created by airborne radio transmitters on input ports of airborne receivers. 2) The major sizes of the area of potential interference interacting (line of sight area). That is specify a multiplicity of an EMF ensemble at aircraft altitude (to 104-106 radio signals created by the land-based radio transmitters of various services) which are exceeding the thresholds of an on-board receivers susceptibility 3) At rather high cruising altitude of modern jet aircrafts owing to their significant remoteness both from the ground surface, and from low-altitude vehicles (turbo-prop aircrafts, UAV, helicopters, dirigibles, etc.), the dynamic range of EMF levels at on-board receiving antennas, created by land-based and low-altitude systems is rather insignificant; excess of the dynamic range of aircraft receivers on intermodulation by input EME dynamic range, as a rule, is improbable. 4) Essentially other EME occurs in situations, inherent in mean and small altitudes of airplanes at their operation in conditions of a) high terrestrial density of land radio systems of various services and under the complex relief when high- power land-based radio transmitters allocated on elevations up to 3-4 km above sea level; b) mass application of different UAV; in these cases the air traffic management (ATM) limitations which eliminate the dangerous approaching of flight vehicles on distances and altitudes, do not eliminate approaching of radiating UAV to © 2017 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works. DOI: 10.1109/EMCEurope.2017.8094819