Collaborative Covert Communication Design Based on Lattice Reduction Aided Multiple User Detection Method

Spread spectrum communication is a typical scheme for covert communication because of its low detectability and antijam characteristic. However, the associated design concerns multiple factors, such as cochannel multiple access interference (MAI) and spread spectrum gain. In this paper, the lattice reduction theory is applied to MAI cancellation of spread spectrum communication and a novel lattice reduction aided multiple user detection method is proposed. The near maximum likelihood (ML) performance of MAI resistance is verified by simulation and theoretical analysis. The superiority of detection performance in strong MAI scenarios is especially addressed. Based on the algorithm, a collaborative covert communication system design is proposed. Low-power covert signals can be transmitted at a higher bit rate with the same coverage as more high-power cochannel signals. The covert transmission performance can be improved significantly compared to traditional designs.

Simulation and Analysis of Linear Multiple User Detection Based on Simulink

In order to study the feasibility of linear Multiple User Detection (MUD) used in multi-objective spread spectrum TT&C, mathematical models of Decorrelation Algorithm (DEC) and Minimum Mean Square Error Algorithm (MMSE) are built. Simulation framework based on Simulink is given. Two algorithms are compared with traditional single user detector. The results of simulation show the two linear MUDs are better than traditional single user detection.