نوع مقاله : مقاله پژوهشی
نویسندگان
1 دانشگاه تربیت مدرس / دانشکده مهندسی برق و کامپیوتر/ مخابرات سیستم
2 استاد دانشکده مهندسی برق و کامپیوتر دانشگاه تربیت مدرس
3 دانشگاه تخصصی فناوری های نوین آمل
چکیده
کلیدواژهها
عنوان مقاله [English]
نویسندگان [English]
This work discusses covert communication and information theory security in a network with an untrusted relay. In this article, a scenario is proposed and evaluated in which the source and destination are equipped with multiple antennas and communicate with each other by the help of a single antenna untrusted relay. The warden is also considered to be equipped with multiple antennas and based on total received power by all antennas, he decides on present or absence of communication. Considering the limitation of the total transmit power, the constrained optimization problem is formulated to maximize the secrecy rate subject to satisfying covert communication requirements. To solve the single-objective constrained problem, the idea of converting the constrained problem into a multi-objective problem is proposed. Finally, we employ the non-dominated sorting genetic algorithm I (NSGAI) to solve it.
If ergodic secrecy rate is considered as a measure of efficiency, comparing the proposed solution with exhaustive search shows a gap of about 6.88 % and proposed solution is efficient. If, the source employs maximum ratio transmission method toward the untrusted relay in the first phase, the ergodic secrecy rate is improved by 9.48 % and 11.53 % compared to best antenna selection and random antenna selection, respectively. A higher secrecy rate can be obtained by using the maximum ratio transmission method toward the untrusted relay by the destination to transmit the artificial noise signal in the first phase. Furthermore, the greater number of source’s antennas, need to the more untrusted relay distance from the source.
کلیدواژهها [English]
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