Fangbiao Li

Security in Single-Input Single-Output Multiple-helpers Wireless Channel

Security is an important issue in the field of wireless communication. In this paper, the security problem of Single-input Single-output Multiple-helpers (SISOMH) wireless channel is considered. The SISOMH wireless channel, where artificial noise is utilized, is designed to prevent eavesdropping. But the artificial noise may be invalid due to the inherent security weakness. We point out that the SISOMH scheme is not safe through by matrix analysis. Then, a Helper Transmission Parameter Optimization (HTPO) scheme is proposed to fix the flow.

Securing Communication via Transmission of Artificial Noise by Both Sides: Bipolar-Beamforming Optimization

The paper considers the secure transmission in a wireless environment in which both the transmitter (Alice) and the legitimate receiver (Bob) send artificial noise (AN) to interfere with the eavesdropper (Eve). Optimal design is analyzed in detail for this AN-by-both-side model to deal with Eve’s stochastic channel condition and random spatial distribution. Bipolar-beamforming is first proposed to jointly design Alice and Bob’s transmitting signals. By optimally assigning the transmitting antenna for Bob and allocating the power ratio between Alice’s information and the AN signal, maximum secrecy capacity can be achieved. Simulation is done to illustrate the process of bipolar-beamforming optimization. Results show that the AN-by-both-side model has good secrecy performance on both average and extreme conditions as Eve approaches Alice or Bob.

Research on the Multiple-Input Single-Output Channel under Attack

The problem we consider is the security communication in MISO (Multiple-input Single-output) scenario. The scenario is connected via wireless signal between two points: the transmitter and the receiver. We assume that transmitter has multiple antennas while receiver has one. In recent papers, they assume that the useful information can be received by the indeed receiver completely but not the eavesdropper. In this paper we take the identity of active attacker to superimpose the attack signal which uses high power all-directional antennas to inject on the original signal. We do the analysis and research on the defect of MISO wireless channel with the mutual information as the mathematical description quantity. This Paper elicits and defines the concept of wireless channel information loss rate. In the end, the MISO security communication solutions against the active attack are given using null space connection technology.

Robust MIMO beamforming and power allocation for artificial noise generated by both transmitter and receiver

This paper is concerned with the secure MIMO transmission in a classic three-node network, in which both the transmitter (Alice) and the receiver (Bob) simultaneously send artificial noise (AN) to impact the channel of the eavesdropper (Eve). Only statistical information about the eavesdropper channel is available. Compared to previous works, this paper studies the scenario in which the main channel are also time-varying and goes through Rayleigh fading. Expected secrecy rate is adopted to evaluate the performance of this model. Robust beamforming and power allocation are proposed to maximize the lower bound of the expected secrecy rate. Numerical results show that with the increase of Bobs AN power, the best practice is to allocate more dimensions for emitting AN and at the same time distribute a greater proportion of Alices power to information symbols.

A New Model for Reliable and Secure Multicast

In computer network, multicast is an efficient scheme for one-to-many and many-to-many communication. Although research on multicast has begun as early as the rise of Internet, multicast is still not widely deployed in the current backbone Internet. With the coming of Cloud Computing and Internet of Things, the distribution of huge amounts of data relies heavily on communication among multiple parties, and multicast has its inherent advantage dealing with these scenarios. This paper analyses the vulnerabilities and deficiencies of the current multicast implementation and proposes a new model to support reliable transmission and security in multicast. Network service and the pricing model are integrated into the model to best exploit the value of multicast.

An achievable rate region of a three-receiver BC with degraded message sets and side information

In this paper, a three-receiver (named as one-receiver two-eavesdropper) discrete memoryless broadcast channel (DM-BC) with three degraded message sets and side information is studied. The main objective of this paper is to present a theorem so as to give an achievable secrecy region for this one-receiver two-eavesdropper DM-BC with the side information available at the transmitter. In the achievability proof scheme, we use the superposition coding scheme to divide the available randomness into different levels for misleading the eavesdroppers. We establish the achievable secrecy region by using a combination of Gelfand-Pinsker binning scheme and rate splitting technique. Achievability in this case also follows from the new idea of Nair-El Gamal indirect decoding. The achievable secrecy region of this paper subsumes the steinberg rate region for two-receiver degraded BC with the side information as well as the secrecy capacity region for one-receiver two-eavesdropper DM-BC with no side information as its special cases.

Secure Communication for a Class of Broadcast Channel with Feedback

This paper investigates the secure data transmission in the broadcast channel with noiseless feedback by using the information-theoretic method. We consider transmitting a private message and a common message to two receivers, of which the common message is to be decoded by both receivers while the private message is only for the intended receiver. The channel to the intended receiver is assumed to be independent of that to the other receiver. Feedback from the output of the intended receiver is used as a shared secret key to enhance the secrecy in the transmission. The capacity-equivocation region and the secrecy capacity of this new model are obtained. We find the secrecy capacity is enhanced by using feedback, even in the case that the other receiver is in a better position than the intended receiver. In addition, our results generalize the secrecy capacity of the degraded wiretap channel with secure feedback, and the capacity region of the degraded broadcast channel.

Improving the Secrecy Rate via Combining the Artificial Noise with the Masked Beamforming Scheme

This paper considers the secure communication via combining the artificial noise with the masked beamforming scheme. In this scenario, the transmitter is equipped with multi-antenna while each of the eavesdroppers is equipped with only one antenna, and the legitimate receiver has a receiving antenna and a transmitting antenna, respectively. The transmitter simultaneously transmits a beamformed secret information-bearing signal to a legitimate receiver and artificial noise (AN) to the eavesdroppers. The legitimate receiver sends the AN to confuse the eavesdropper while receiving the desired signal from the transmitter. We compare the proposed scheme that combining the AN with masked beamforming with no beamforming vector scheme, and derive that the combined strategy obviously improved the secrecy rate.

Maximizing the Secrecy Rate of Wiretap Channel via DF-Based Cooperative Scheme

This paper addresses the physical layer security of a two-hop decode-and-forward (DF) wireless relay network in the presence of several eavesdroppers. The wiretap channel model consists of a source, several eavesdroppers, couples of trusted relays and a destination. For this DF based cooperative relay scheme, the relays use different code words independent of the source code words to transmit a weighted version of the recoded messages as with the source messages to the legitimate receiver and jam the eavesdropper. We fix the transmit power of the source ( Ps ) to obtain the weights for secrecy rate maximization, assuming that global channel state information (CSI) is available. The maximization problem can be made to a generalized eigenvector problem, and it is easy to obtain the corresponding eigenvector that is the optimal relay weight vector by using the matrix computations. The closed-form optimal solution is derived for the relay weights that maximize the achievable secrecy rate.

Research on Secrecy Communication via Bilateral Artificial Noise Transmitting

The problem that we consider is the secrecy communication in bilateral transmitting scenario. The model is connected via wireless signal between two points: the transmitter and the receiver. We assume that the transmitter has a single transmit antenna while the receiver has two (one transmit, one receive). In recent papers, it is shown that artificial noise could be used to increase the secrecy capacity. However, for one transmitter antenna case, helper nodes can only be used. In this paper we propose a new 2-Stage artificial noise sending method to substitute helper nodes. So the cost of helper nodes can be saved. The comparison of artificial noise transmitting with Beamforming is given in this paper. It can be proved to increase the secrecy capacity via our approach.