Algorithm

MIMO

Encryption

Precoding

Noma

Telecommunications

Computer science

Mathematical optimization

Artificial noise

Secure communication

Computer network

Mathematics

Leverage (statistics)

Geometry

Physical layer

Transmission (telecommunications)

Channel (broadcasting)

Wireless

Convex optimization

Optimization problem

Regular polygon

Machine learning

Telecommunications link

IEEE Transactions on Communications

Integrated sensing and communication (ISAC) is an up-and-coming technique for future 6G networks. However, the communication message carried by the detection waveform will face the risk of being eavesdropped, which leads to the challenge of wireless security for ISAC networks. In this paper, we leverage non-orthogonal multiple access (NOMA) to support more users for the ISAC network, with the precoding well designed to guarantee the security. Specifically, we formulate a joint precoding optimization problem to maximize the sum secrecy rate for multiple users via artificial jamming, where the superimposed signal for NOMA users can be concurrently employed for the target detection. Since the optimization problem is non-convex, it is transformed into a convex one based on successive convex approximation (SCA), where the Taylor’s approximation and second-order cone (SOC) constraint are further applied. Then, we propose an iterative algorithm, through which the original optimization problem can be solved effectively. Simulation results show that the proposed secure NOMA-ISAC scheme can guarantee the secure transmission while ensuring the sensing performance.

Secure Precoding Optimization for NOMA-Aided Integrated Sensing and Communication