Ефективність прямого розширення спектра в системах зв’язку з таймерними сигналами

Abstract

Запропоновано метод синтезу шумоподібних сигналів на основі таймерних сигнальних конструкцій (ТСК) і ортогональних псевдовипадкових послідовностей з бінарною фазовою модуляцією ФМ-2 (BPSK) у системах зв’язку з кодовим розділенням каналів (КРК). Оцінено ефективність використання ТСК в індивідуальних каналах з обмеженою смугою частот окремих абонентів системи передавання з КРК. Наведено алгоритм вибору параметрів таймерних сигналів і псевдовипадкових послідовностей у разі формування шумоподібних сигналів. Показана перспектива використання таймерних сигнальних конструкцій в конфіденційних системах зв’язку для завдання підвищення структурної прихованості шумоподібних сигналів. Cryptographic systems are considered to be quite an effective mechanism for the protection of information, and they are used mainly in the upper levels of the reference model OSI. However, analysis of trends in cryptography and cryptanalysis confrontation shows that no matter how reliable was not used newly established cryptographic system, discrediting it eventually becomes apparent. Taking into account this fact, promising is the development of additional mechanisms for the protection of information circulating on the network. In the last decade a special interest in acquiring methods of information security, which are implemented on the ground level of the OSI reference model and are aimed at significant reduction in the effectiveness of the means of unauthorized access (unauthorized access), which include: an attempt to detect the fact of transfer and violation of the integrity of a transmitted message, intercepting communication session and recognition of the structure of the signal structures with subsequent decoding of cryptograms, etc. One of the ways of confrontation of confidential communications with NSD can use complex signals with cryptoprotection structure. A prerequisite for the formation of the requirements for the properties of structures and algorithms for signal transfer to ensure secrecy of information exchange, is the account of algorithmic and technological potential of modern means of unauthorized access. It follows that the relevant information to improve the security of information transfer is the study on the creation of algorithms of functioning of confidential communications and signal synthesis designs that enhance the various indicators of secrecy. In view of this, the aim is to develop a method of forming a broadband noise-like signal based on the timer signal design (TSC) with binary phase demodulation. A method for synthesis of noise signals based on the TSC and orthogonal pseudorandom binary phase modulation with the FM-2 (BPSK) communication systems, code division multiplexing (AAC). The estimation had been performed of utilization efficiency of TSC in the individual channels with limited bandwidth transmission systems of individual subscribers to the CBC. An algorithm is proposed for selecting parameters of timing signals and pseudo-random sequence of the formation of noise-like signals. The prospects of using timer signal designs in confidential communication systems for the task of improving the structural stealth noise-like signals.