Jinhui Lu

Robust Secure Transmission of Using Main-Lobe-Integration-Based Leakage Beamforming in Directional Modulation MU-MIMO Systems

In this paper, we make an investigation of robust beamforming for secure directional modulation in the multiuser multiple-input and multiple-output systems in the presence of direction angle measurement errors. When statistical knowledge of direction angle measurement errors is unavailable, a novel robust beamforming scheme of combining main-lobe-integration and leakage is proposed to simultaneously transmit multiple different independent parallel confidential message streams to the associated multiple distinct desired users. The proposed scheme includes two steps: designing the beamforming vectors of the useful confidential messages and constructing artificial noise (AN) projection matrix. Here, in its first step, the beamforming vectors for the useful confidential messages of desired user

On the Auction-Based Resource Trading for a Small-Cell Caching System

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Secure precise transmission with multi-relay-aided directional modulation

are given by minimizing the useful signal power leakage from the main-lobe of desired user

On Impact of Earth Constraint on TDOA-Based Localization Performance in Passive Multisatellite Localization Systems

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On Social-Aware Content Caching for D2D-Enabled Cellular Networks with Matching Theory

to the sum of main-lobes of the remaining desired directions plus main-lobes of all eavesdropper directions. In its second step, the AN projection matrix is constructed by simultaneously maximizing the AN power leakage to all eavesdropper directions such that all eavesdroppers are disrupted seriously, where AN is viewed by the transmitter as a useful signal for eavesdroppers. Due to independent beamforming vectors for different desired users, a more secure transmission is achieved. Compared with conventional nonrobust methods, the proposed method can provide a significant improvement in bit error rate along the desired directions and secrecy-sum-rate toward multiple desired users without needing the statistical property or distribution of angle measurement errors.

Power Allocation Strategy of Maximizing Secrecy Rate for Secure Directional Modulation Networks

In this letter, we propose an auction-based resource trading scheme between a network service provider (NSP) and multiple content providers (CPs). The NSP is in charge of a number of small-cell base stations (SBSs), while each CP provides content downloading services to its affiliated mobile users (MUs). By treating the SBSs as a kind of resources, the NSP leases SBSs to the CPs for caching their popular contents, thereby reducing the downloading latency of the MUs. We first establish the utility functions of the NSP and CPs. Then, we maximize the utilities of both sides by formulating an iterative auction problem, in which the NSP (auctioneer) communicates with the CPs (bidders) in an iterative manner for achieving optimal price and resource allocations. Furthermore, to avoid being cheated from the CPs, we adopt an ascending-bid auction mechanism such that the CPs do not have motivations to cheat the NSP for a lower price. Numerical results show that our proposed scheme can effectively allocate SBSs to the CPs and prevent each CP from cheating the NSP for gaining a higher profit.

A Multi-Rounds Double Auction Based Resource Trading for Small-Cell Caching System

In the conventional directional modulation (DM) system without relay aiding, when the eavesdropper locates within the main-beam of the desired direction, it can intercept the confidential message from source Alice. In this paper, we propose a strategy to enhance physical-layer security of direction modulation in wireless transmission with the help of multi-relay cooperation. In this scenario, the confidential messages are forwarded to the desired destination receiver, and the artificial noise (AN) is enforced to the eavesdroppers with the aid of multi-relays and direction modulation such that the eavesdropper can not successfully recover the useful information from its received signals. The simulation results show that the proposed method achieves a significantly higher signal-to-interference-plus-noise ratio (SINR) peak at the destination position than at other positions outside the main-beam of the desired position and its secrecy rate performance at undesired position is so poor that the secure transmission is guaranteed.

Alternating Iterative Secure Structure between Beamforming and Power Allocation for UAV-aided Directional Modulation Networks.

In a passive multisatellite location system with Earth constraint (EC), the localization problem of time differences of arrival (TDOAs) is formulated as a quadratic optimization (QO) problem with two equality constraints: EC and variable constraint (VC). Which constraint is more important? To evaluate the importance of the two constraints, the original QO problem with both EC and VC is relaxed into two individual QO problems with only one equality constraint EC or VC being kept. A convex combination operation is performed on the two optimal solutions associated with the two relaxed QO problems to form a new weighted solution. Numerical simulation results show that the new weighted coefficient can achieve the Cramer–Rao lower bound with EC as the weighted factor of the solution exploiting only VC tends to zero, and increasing the value of this weighted coefficient will gradually degrade the overall localization performance. Thus, we conclude that the EC plays an extremely important role in improving the performance of TDOA-based localization.

Robust Directional Modulation Design for Secrecy Rate Maximization in Multi-User Networks.

In this paper, the problem of content caching in 5G cellular networks relying on social-aware device-to-device communications (DTD) is investigated. Our focus is on how to efficiently select important users (IUs) and how to allocate content files to the storage of these selected IUs to form a distributed caching system. We aim at proposing a novel approach for minimizing the downloading latency and maximizing the social welfare simultaneously. In particular, we first model the problem of maximizing the social welfare as a many-to-one matching game based on the social property of mobile users. We study this game by exploiting users’ social properties to generate the utility functions of the two-side players, i.e., content providers (CPs) and IUs. Then we model the problem of minimizing the downloading latency as a many-to-many matching problem. For solving these games, we design a many-to-one IU selection (MOIS) matching algorithm and a many-to-many file allocation (MMFA) matching algorithm, respectively. Simulation and analytical results show that the proposed mechanisms are stable, and are capable of offering a better performance than other benchmarks in terms of social welfare and network downloading latency.