The authentication of transmitting terminal in present physical-layer security method based on wireless channel character is implemented by checking the pilot signal sent by it, and missing detection often happens. A new kind of physical-layer authentication and key distribution mechanism based on equivalent channel is presented. The equivalent channel is built by encrypting keys with channel character of multi time slots, as a result difference of different channels is mapped onto transmitting distortion. And mutual information of delivering and receiving terminals channel characters can be told by correctness of the transmission, thus the key distribution and authentication are implemented at the same time. Analysis and simulation reveal that key distribution performance in this method is same as the existing one, and the attack can be recognized in circumstances of channels with strong correlation.
The authentication of transmitting terminal in present physical-layer security method based on wireless channel character is implemented by checking the pilot signal sent by it, and missing detection often happens. A new kind of physical-layer authentication and key distribution mechanism based on equivalent channel is presented. The equivalent channel is built by encrypting keys with channel character of multi time slots, as a result difference of different channels is mapped onto transmitting distortion. And mutual information of delivering and receiving terminals channel characters can be told by correctness of the transmission, thus the key distribution and authentication are implemented at the same time. Analysis and simulation reveal that key distribution performance in this method is same as the existing one, and the attack can be recognized in circumstances of channels with strong correlation.
Due to the limited reciprocity of wireless channel, most existing physical-layer security method based on channel characteristics is implemented by repeatedly interacting to generate consistent keys, which resulting in large overhead. This paper proposes a secure transmission scheme based on equivalent channel which is built by random scrambling codes generated from channel characteristics. To improve efficiency and reliability, the legitimate senders scramble the encoded signal and the receivers mitigate the non-reciprocal effect by channel decoding, rather than interacting information to obtain consistent scrambling codes. The channel capacity and security capacity of the scheme are analyzed and simulated in Rayleigh channel model. The results show that the difference of channel characteristics significantly degrade the eavesdropper's receiving performance, so that the received signal cannot be decoded correctly.
This paper proposes a new channel state based secure wireless communication mechanism to realize secure communication with a pre-equalization function in a physical layer. Researches of physical layer security have been proposed to achieve secure communication in physical layers. On the contrary, there are a few issues where terminals in a same direction can receive a message, overhead due to complex control mechanisms, special hardware, etc. This paper focusses on practical wireless communication environment, where multi-path signals are received at a receiver. It is common knowledge that a channel state according to multi-path signals is different when a position of a receiver is different. The transmitter of proposed scheme transmits an optimized signal to a receiver with pre-equalizing the signal according to the channel state between the transmitter and the receiver. Therefore, only the receiver that has the same channel state for the pre-equalizing can obtain the high quality signal from the transmitter, and can demodulate the signal correctly. As a result, eavesdroppers around the transmitter cannot equalize the received signal before a demodulation process for the received signal because they exist at a different place of the receiver. The numerical results show that the proposed scheme can realize secure communication in typical wireless channel models. It means that a legitimate receiver can demodulate a signal correctly and eavesdroppers suffer from demodulation errors. As a result, we can find that the proposed scheme can utilize a channel state as an encryption key in physical layer security communication.
Physical-layer key generation technology requires information reconciliation to correct channel estimation errors between two legitimate users. However, sending the reconciliation signals over the public channel increases the communication overhead and the risk of information leakage. Aiming at the problem, integrated secure communication schemes using non-reconciled keys have attracted extensive attention. These schemes exploit channel coding to correct both inconsistent keys and transmission error bits. Meanwhile, more redundant code bits must be added to correct errors, which results in a lower secure transmission rate. To address the problem, we analyze the merit of channel correlation between non-reconciled key generation and secure transmission. Inspired by this, we propose a non-reconciled physical-layer keys-assisted secure communication scheme based on channel correlation. First of all, the signal frame is designed to make use of channel correlation between non-reconciled key generation and secure transmission. Based on the channel correlation, non-reconciled keys are then generated from the wireless channel to encrypt transmitted data. Moreover, an adaptive coding algorithm based on the equivalent channel is presented to encode the data bits before encryption, to guarantee reliable transmission. Finally, theoretical analysis and simulations demonstrate the significant performance of the proposed scheme in terms of low bit error ratio and high secure transmission rate.
The new power system is the national development strategy and development direction of smart grid. Communication is the basis of the development of the new power system. in the distribution automation business, communication is the weakest link. In order to make electric power communication develop more smoothly, we should improve our awareness of security issues. Because of the particularity of electric power communication, it often has very high requirements for the security of communication. In order to effectively ensure the security of electric power communication data, data encryption technology can be applied to the data transmission process, and the security of information transmission can be improved through the application of encryption and decryption keys.Physical layer key generation technology is a security technology that uses wireless channel characteristics as a random source to generate keys. This technology uses the anisotropy, time variation and spatial uniqueness of wireless channels to generate random sequences, which is different from traditional encryption methods. Physical layer key generation technology does not require the key management and distribution of a third party trusted organization. In theory, it can achieve one encryption at a time to achieve the absolute security of Shannon confidential communication[1]. This paper first briefly introduces the wireless channel physical layer key generation model and the general process of key generation scheme based on channel feature quantization, and then studies the improved optimization scheme based on traditional channel detection, preprocessing and quantization algorithm, so as to effectively improve the key generation performance.
Addressing the problem of wireless physical layer security transmission for finite alphabet input systems,a spatial modulation secure transmission method is proposed.On the basis of information theory,the method utilizes the receive antenna indices of multiple-input multiple-output (MIMO) system to bear information,and randomizes the eavesdropper’s equivalent channel by switching the receive antennas,which can guarantee physical layer security transmission.First,the different receiving performances of the legitimate user and eavesdropper are analyzed in the spatial modulation secure transmission system.Second,the mutual information and secrecy mutual information of the transmission system are calculated,and two sufficient conditions that ensure positive secrecy mutual information are pointed out.Finally,an estimation algorithm of mutual information is provided.Moreover,the symmetry of finite alphabet set is exploited to decrease the computational complexity.Theoretical analysis and numerical simulation results verify the availability of the security transmission method.
User authentication (UA) supports the receiver in deciding whether a message comes from either the claimed transmitter or an impersonating attacker. Information-theoretically secure authentication can be implemented by using either a secret (symmetric key) shared between both the legitimate users or the transmission medium over which the message is transmitted [physical-layer authentication (PLA)]. We analyze these solutions when the physical-layer channel is the unique randomness source for either generating the key or performing PLA. For the symmetric-key-based UA approach, we resort to a secret key agreement. Moreover, we also consider an asymmetric-key-based UA based on the public-key (proven to be semantically secure), where the channel is used as an entropy source at one device only. We define the secure authentication rate at which the probability that the UA attack succeeds goes to zero as the number of independent and identically distributed variables describing how the channel goes to infinity. Both passive and active attacks are considered, and by numerical results, we compare the various UA schemes.