Use of spread spectrum systems in telecommunications is studied. It is shown that spread spectrum techniques can substantially enhance noise and interference immunity in the currently deployed information transmission networks. Primitive polynomials are proposed to obtain respective spreading codes. A spreading code consisting of 1023 chips is synthesized and its characteristics are studied.
It is deduced that powerful interferences can exceed dynamic range of the receiving part of the system and, as a result, deteriorate information transmission. To overcome this problem, utilization of limiters is proposed, in which limitation level equals that of the internal noise of the receiving part. Computer simulation is employed to test the performance of the proposed solution. Performance of the spread spectrum system for information transfer is studied both without the limiter and with the limiter.
Research results show that, for binary modulation, performance of the system with limitation and without limitation is nearly identical while limiters can substantially reduce requirements for the dynamic range.
Compared to the existing approaches, it is proposed to use the synthesized spreading coding sequence with the limitation technique in practical implementations of those telecommunication networks, in which noise immunity and transmission concealment are required, such as in unmanned aerial vehicles. This can replace currently used approaches, such as frequency hopping, transmission power adjustment and antenna pattern changes.

This work is about the definition of cyber threats in the information system. The cyber threats lead to significant loss of network resources and cause the system disability as a whole. Detecting countermeasures in certain threats can reduce the impact on the system by changing the topology of the network in advance. Consequently, the interruption of a cyberattack forces the intruders to seek for alternative ways to damage the system. The most important task in the information system work is the state of network equipment monitoring. Also it’s the support of the network infrastructure in working order.
The purpose of the work is to develop a method for detecting cyber threats for the information system. The system can independently detect cyber threats and develop countermeasures against them. The main feature of the counteractions is to protect network nodes from compromising.
To ensure the functional stability, the most important issues are providing safety metrics. This technique allows to increase the functional stability of the system, which works in real time.