Physical layer secrecy in wireless communication is a new approach of information security and has emerged into a fascinating topic attracting lots of research. Ultra-WideBand (UWB) technology in conjunction with Time-Reversal (TR) is used to improve the speed of transmission and reduce the cost and complexity for the receiver. This paper focuses on the evaluation of physical layer secrecy in Multi-Input Multi-Output (MIMO) UWB system with TR and compares to the system without using TR technique to clarify the advantages of this technique. Simulation results show that the secrecy capacity of UWB system is significantly improved when applying TR technique.
Physical layer secrecy in wireless communication is a new approach of information security and has emerged into a fascinating topic attracting lots of research. Ultra-WideBand (UWB) technology in conjunction with Time-Reversal (TR) is used to improve the speed of transmission and reduce the cost and complexity for the receiver. This paper focuses on the evaluation of physical layer secrecy in Multi-Input Multi-Output (MIMO) UWB system with TR and compares to the system without using TR technique to clarify the advantages of this technique. Simulation results show that the secrecy capacity of UWB system is significantly improved when applying TR technique.
Traditionally, spread-spectrum systems have been employed to provide low probability-of-intercept (LPI), low probability-of-detection (LPD) performance at the physical layer, but the messages transmitted over such a system are still encrypted with a powerful cipher to protect their secrecy. However, it has recently been suggested that the cryptographic security of the system can be enhanced by exploiting physical properties of ultra-wideband (UWB) signals. With an eavesdropper observing the communications over multipath channels between two legitimate partners sharing a secret key of a limited length, we consider both coherent and reference-based UWB schemes to enhance security. The security of the legitimate nodes is achieved by signal attributes based on the secret key, giving them an advantage over the adversary. In particular, we propose transmission schemes and investigate the physical layer security performance of UWB systems intended for coherent reception and UWB transmitted-reference (TR) systems in IEEE 802.15.4a multipath environments. Critical to the TR scheme is employing true randomness to keep a sophisticated adversary from decoding the signal coherently. Numerical results for IEEE 802.15.4a channel models reveal not only that the proposed schemes provide promising support for higher-layer cryptographic protocols, but also, perhaps surprisingly, that the baseline UWB TR system can demonstrate better security tradeoffs than the baseline UWB system intended for coherent reception under the IEEE 802.15.4a channel model.
In this paper, we focus on the physical layer secrecy performance analysis of Ultra Wideband system consisting of a multi-antenna transmitter using transmit antenna selection and single antenna receiver, in the presence of a single antenna passive eavesdropper over Rayleigh fading channel. Specifically, the exact closed-form expressions of probability of existence of secrecy capacity and the secrecy outage probability are derived by using statistical characteristics of the signal-to-noise ratio. The analytical results are verified by Monte-Carlo simulations.
In multiple-input-multiple-output (MIMO) wireless communications, Space Shift Keying (SSK), Spatial modulation (SM) and Generalized Space Shift Keying (GSSK) are three novel MIMO modulation techniques, that can greatly reduce the complexity of MIMO systems. This paper investigates the physical-layer security in typical MIMO systems of these three modulations. We present an exhaustive analysis of secrecy rate for multiple antennas destination and eavesdroppers receivers. Without eavesdroppers channel information, both achievable secrecy rate and bit error rate (BER) are studied through joint modulated signal and jamming signal transmission. Our simulation results demonstrate that the proposed proactive source jamming method achieves improvement of secrecy rate and improved BER performance for multi-antenna users.
Broadband wireless communication is implemented primarily in a complicated environment. The complex environment with time-varying multi-path propagation characteristics will seriously affect the performance of communication. To solve the problem of insecurity in information transmission in wireless channels, in this paper a system is modeled by using the multi-input single output eavesdropping channel model and the security of information transmission through time reversal technology is ensured. Another problem is that the information focuses on the receiving point. Owing to the temporal and spatial focusing characteristics of the time reversal technology the information near the receiving point can be eavesdropped easily. To solve this problem, a secure transmission scheme based on time reversal technology with artificial noise interference on the transmitter side is proposed. One of the core technologies to solve this problem is to introduce the environment adaptive technique–time reversal in the wireless link. Further, the problem of a wiretap channel in physical layer security research has become a popular research topic in recent years. To solve the problems about the physical layer wiretap channel and multi-path fading in wireless channels, a novel concept combining time reversal technology with physical layer security technology is proposed. In this paper, a physical layer secure transmission scheme based on the joint time reversal technique and artificial noise at the sending end is proposed for the wireless multi-path channel. First, in a typical wiretap channel model the time reversal technique is used to improve the security of the information transmission process by using the properties of spatial and temporal focusing. It refers to the fact that information can be focused at a given moment and in space. Second, as the information is easily eavesdropped near the focus point, artificial noise is added to the sending end to disrupt the ability of the eavesdropper to eavesdrop. The artificial noise has no effect on legitimate user due to the use of null-space artificial noise in legitimate user. Based on this scheme, a closed expression, such as secure signal-to-interference and signal-to-noise ratio, an achievable secrecy rate and bit error rate are obtained, and the influences of the number of antennas, signal-to-noise ratio, and artificial noise are analyzed. The theoretical analysis and simulation results show that the proposed scheme has a higher secrecy signal-to-noise ratio, a higher rate of secrecy, and a lower bit error rate of the legitimate user than the the existing physical layer security schemes.
Large-scale multiple input multiple output (MIMO) wireless system is regarded as a solution to provide high speed connection for exponentially increasing wireless subscriptions for emerging cyber-physical systems (CPSs) and Internet of Things. In order to realize its full potential, there are several challenges to be addressed to achieve high secrecy rate or data rate. In this paper, we analyze outage probability for secrecy rate in MIMO wireless systems in the presence of eavesdroppers and jammers for CPS devices. Our proposed approach takes into account the impact of jammers while finding the best response to minimize the jamming/interfering effect (or to enhance the secrecy rate) and the impact of eavesdropper in secrecy rates of the users. We present formal analysis for secrecy outage probability and interception probability considering Rayleigh fading scenario. The performance is evaluated by using numerical results obtained from Monte Carlo simulations. Numerical results indicate that the system performance is improved significantly when the users adapt their transmit vectors based on their observed interference values. Furthermore, the secrecy outage probability increases with power of jammer and the secrecy capacity decreases when jammer power increases. We observed that the proposed approach outperforms the other existing approaches.
This paper addresses the confidentiality of wireless communications in industrial internet-of-things environments by investigating the feasibility of secret key generation for link-layer encryption using ultra wideband (UWB) signals. Taking advantage of the nanosecond-level temporal resolution offered by ultra wideband, we exploit channel reciprocity to extract highly detailed, noise-like channel measurements, in line with the physical-layer security paradigm. Three key generation algorithms, operating in both the time and frequency domains, are evaluated using real-world data collected through a dedicated measurement campaign in an industrial setting. The analysis, conducted under realistic conditions, examines the impact of practical impairments, such as imperfect channel reciprocity and timing misalignments, on the key agreement rate and the length of the generated keys. The results confirm the strong potential of ultra wideband technology to enable robust physical-layer security, offering a viable and efficient solution for securing wireless communications in complex and dynamic industrial internet-of-things environments.