List of Articles نویز مصنوعی

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  1 - Covert Communication Using Jointly Spread Spectrum and Artificial Noise
  Morteza Shafiee Neyestanak Iman Kazemi
  Covert Communication technique is developed for LPD communication in military and civil applications. Artificial Noise (AN) is the method to confuse eavesdropper and assure data transmission. But, generating AN in wide range of frequencies and times is very challenging. More

  Covert Communication technique is developed for LPD communication in military and civil applications. Artificial Noise (AN) is the method to confuse eavesdropper and assure data transmission. But, generating AN in wide range of frequencies and times is very challenging. Furthermore, it reveals the transmitter or challenges it for synchronization to confuse eavesdropper about environmental noise. This paper proposes a method based on Spread Spectrum as well as self-jamming as AN to solve the problems. By spreading the spectrum, we can generate AN in wide range of frequencies and times, at low power and cost-effective manner. Consequently, there is no need to synchronization. Simulation and numerical results indicate, partial band jammer, effectively confuse the eavesdropper by 1.8 dB margin at JSR = -5 dB. In the situations, transmitter and receiver may communicate at BER = 10^-3 for Eb/N > 8.3 dB. The paper simulates the proposed method for various types of jamming and reports the results where, multitone jamming is rejected for this application as artificial noise. Single-tone jammer also can confuse the eavesdropper by 2.6 dB margin at JSR = -5 dB and TRX communications quality equal to BER = 10-3 for Eb/N > 10.9 dB Manuscript profile
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  2 - Optimal Power Allocation for Maximizing Secrecy Rate in Physical Layer Security Using Frequency Diverse Array Directional Modulation and Artificial Noise
  Mahdi Tayyeb Massoud Hossein Khaleghi
  The directional modulation is a prominent and practical technique for enhancing the physical layer security in modern communication systems. In this method, the message signal is modulated by an array of antennas and transmitted in a specific direction to the legitimate More

  The directional modulation is a prominent and practical technique for enhancing the physical layer security in modern communication systems. In this method, the message signal is modulated by an array of antennas and transmitted in a specific direction to the legitimate receiver, such that in other directions, the signal is destroyed and not receivable by eavesdroppers. By incorporating random frequency diverse array directional modulation, secure communication can be achieved in both angular and distance dimensions for the legitimate receiver. However, when the eavesdropper is located near the legitimate receiver, the confidentiality performance of this solution significantly deteriorates. To address this issue, this paper proposes a novel approach that combines artificial noise with random frequency diverse array directional modulation and optimizes power allocation to attain the maximum secrecy rate. Simulation results demonstrate that our proposed approach improves the secrecy rate of the physical layer security by at least one bit per second per hertz compared to the method without artificial noise, and by at least two bits per second per hertz compared to the phased array directional modulation. Manuscript profile