In this paper, we consider a secure communication over the physical layer. The objective of the system is, at the physical layer security, the randomness of the channel and the polar coded aided artificial noise provide the security to the system without any secret key generation in higher layer encryption. Artificial noise will be injected at the last codeword of the confidential bits of polar codes in transmission block. Jamming position algorithm is used to initialize the position of artificial noise. The Bhattacharya parameter is used to select the position of jamming with regard to the reliability of the channel. The legitimate receiver has the knowledge of artificial noise and the confidential bit position, so it will eliminate the AN but Eve does not have the knowledge of jamming position so it cannot eliminate the AN. Simulation results show the performance of secrecy rate and the security gap of the system with the help of adding artificial noise at the last transmission block.
In this paper, we consider a secure communication over the physical layer. The objective of the system is, at the physical layer security, the randomness of the channel and the polar coded aided artificial noise provide the security to the system without any secret key generation in higher layer encryption. Artificial noise will be injected at the last codeword of the confidential bits of polar codes in transmission block. Jamming position algorithm is used to initialize the position of artificial noise. The Bhattacharya parameter is used to select the position of jamming with regard to the reliability of the channel. The legitimate receiver has the knowledge of artificial noise and the confidential bit position, so it will eliminate the AN but Eve does not have the knowledge of jamming position so it cannot eliminate the AN. Simulation results show the performance of secrecy rate and the security gap of the system with the help of adding artificial noise at the last transmission block.
The secrecy rates of the existing practical secrecy coding methods are relative low to satisfy the security requirement of 5G communications. We propose an artificial noise (AN) aided polar coding algorithm to improve the secrecy rate. Firstly, a secrecy coding model based on AN is presented, where the confidential bits of last transmission code block are adopted as AN to inject into the current codeword. In this way, the AN can only be eliminated from the jammed codeword by the legitimate users. Since the AN is shorter than the codeword, we then develop a suboptimal jamming positions selecting algorithm with the goal of maximizing the bit error rate of the eavesdropper. Theoretical and simulation results demonstrate that the proposed algorithm outperforms the random selection method and the method without AN.
In contrast to the network security that relies on upper-layer encryption for the confidentiality and authenticity of communications, physical layer security (PLS) exploits the uniqueness and randomness of the physical channel to encrypt information and enhance the security of the system. In this paper, we study the PLS of a polar-coded wireless communication system. To be more specific, we leverage the unique properties in polar code construction and propose a channel quality indicator (CQI)-based frozen-bit pattern generation scheme. The transmitter employs the Gaussian approximation algorithm to generate the corresponding frozen bit pattern according to the instantaneous CQI of the legitimate link. At the receiver, by leveraging the full channel reciprocity in the time-division duplex (TDD) mode, we can map the CQI to the corresponding frozen bit pattern and correctly decode the received bits. By contrast, the eavesdropper was unable to have the knowledge of the legal channel, and hence cannot determine the frozen bit pattern of the polar-coded bit sequence. Our simulation results demonstrate that by adopting the proposed PLS key generation scheme, Eve was hardly able to correctly decode a complete frame, leading to a high block error rate (BLER), while Bob was able to attain a 10−5 BLER.
In this study, by exploiting the properties of finite‐length polar codes, the authors introduce a physical layer encryption scheme to make secure (from a computational security perspective) and efficient communication between a sender (Alice) and a legitimate receiver (Bob) against both active and passive attacks, simultaneously. To prevent active attacks, two techniques are considered: (i) a novel method is introduced to keep the generator matrix of polar code secret from an active attacker (Oscar); (ii) a proper joint polar encoding/encryption algorithm based on the hidden generator matrix is introduced. Two additional strategies are considered against passive attacks: (i) a new method is introduced to partition the bit‐channels into good and bad bit‐channels and then the scrambled information bits are transmitted over those bit‐channels that are good for Bob but bad for a passive attacker (Eve); (ii) the secret key cryptography is implemented at the physical layer, such that Eve cannot decode the eavesdropped data without the knowledge of the secret key shared between the authorised parties. Besides, this study discusses efficiency analysis results consisting key size, error performance and computational complexity of the proposed scheme.
Abstract The existing physical layer security schemes, which are based on the key generation model and the wire-tap channel model, achieve security by utilizing channel reciprocity entropy and noise entropy, respectively. In contrast, we propose a novel secure transmission framework that combines noise entropy with reciprocity entropy, achieved by inserting reciprocity entropy into the frozen bits of polar codes. Note that in real-world scenarios, when eavesdroppers employ polynomial-time attacks, the bit error rate (BER) increases due to the introduction of computational entropy. To achieve indistinguishability security, we convert the practical physical layer security metric, BER, into the average min-entropy, a widely accepted concept in cryptography. The simulation results demonstrate that the eavesdropper’s BER can be significantly increased without compromising the communication performance of the legitimate receiver. Under concrete parameters we selected, when compared to the joint scheme of physical layer key generation and one time pad, the modular semantically-secure scheme based on the wire-tap channel model, and the simple channel entropy combination scheme, our scheme achieves a message rate approximately 1.2 times, 3.8 times, and 1.4 times better, respectively. Experimental testing validates the feasibility of our scheme.
In this paper,an enhanced physical layer security communication scheme is proposed for the multiple antenna systems. The scheme employing transmit antenna selection and artificial noise,also Alamouti coding,improved diversity gain in legitimate channel with low complexity in the transmitter and receiver,and at the same time efficiently jammed the wiretap channel. Consequently it can increase the system secrecy capacity. We analyze the system secrecy capacity and the impacts of the number of antennas and the power allocation between the information signal and artificial noise. Simulation results demonstrate that the proposed scheme can effectively enhance the physical layer security.
Physical layer security (PLS) has grown in popularity as it guarantees secure and reliable communication between wireless devices without restricting the ability of data analysts to eavesdrop. PLS benefits from the randomization property of the wireless channel, which improves immunity and protects against many dangers of information breaches from eavesdroppers. MIMO and Massive MIMO, which use numerous antennas at the transmitter and receiver ends, are fundamental technologies for improving efficiency in 5G and future network systems. The PLS still requires a significant amount of work before it can be employed in practical systems. The interception of eavesdroppers can be made difficult by adding artificial noise. This paper focuses on the physical layer security considering maximal ratio combining, and artificial noise with beamforming techniques to further enhance the secrecy rate. The proposed work demonstrates that the use of transmitter beamforming with artificial noise can significantly improve the degree of confidentiality of information being transmitted between a transmitter and an intended receiver while making it more difficult for eavesdroppers to intercept. The simulation results in terms of bit error rate show that the proposed method has a significant impact on the error rate performance of the eavesdropper.