On the Transmission Probabilities in Quantum Key Distribution Systems Over FSO Links

Abstract

In this paper, we investigate the transmission probabilities in three cases (depending only on the legitimate receiver, depending only the eavesdropper, and depending on both legitimate receiver and eavesdropper) in quantum key distribution (QKD) systems over free-space optical links. To be more realistic, we consider a generalized pointing error scenario, where the azimuth and elevation pointing error angles caused by stochastic jitters and vibrations in the legitimate receiver platform are independently distributed according to a non-identical normal distribution. Taking these assumptions into account, we derive approximate expressions of transmission probabilities by using the Gaussian quadrature method. To simplify the expressions and get some physical insights, some asymptotic analysis on the transmission probabilities is presented based on asymptotic expression for the generalized Marcum Q-function when the telescope gain at the legitimate receiver approaches to infinity. Moreover, from the asymptotic expression for the generalized Marcum Q-function, the asymptotic outage probability over Beckmann fading channels (a general channel model including Rayleigh, Rice, and Hoyt fading channels) can be also easily derived when the average signal-to-noise ratio is sufficiently large, which shows the diversity order and array gain.

Возможность Построения Модульной Системы Квантового Распределения Ключей В Атмосфере

“…Технологии КРК на физическом уровне гарантируют безопасность передачи информации, а возможность утечки данных может быть связана лишь с несовершенством конкретной реализации технологии [3,4]. Сегодня достигнуты значительные успехи в разработке серийных устройств для КРК в волоконнооптических линиях связи (ВОЛС) [5], а установки КРК в атмосфере пока находятся на стадии демонстрационных макетов [6]. При этом терминалы для атмосферных оптических линий связи (АОЛС) уже давно доказали свою эффективность для передачи больших объемов данных [7,8].…”

Possibility of creating a modular system for quantum key distribution in the atmosphere

“…QKD technologies at the physical level guarantee the security of information transmission, and the possibility of data leakage can only be associated with the imperfection of a specific implementation of the technology [3,4]. Today, significant progress was made in the development of serial devices for QKD in fiber-optic communication lines (FOCL) [5], and QKD units in the atmosphere are still at the stage of demonstration prototypes [6]. At the same time, terminals for atmospheric optical communication lines (AOCL) have long proved their effectiveness for transmitting large amounts of data [7,8].…”