Robust security beam forming method based on multi-objective optimization

Abstract

The invention discloses a robust security beam forming method based on multi-objective optimization. The robust security beam forming method comprises the following steps: step a, establishing a satellite-ground fusion cognitive network under the condition of spectrum sharing of a satellite communication network and a ground cellular network; step b, setting a secondary user signal-to-interference-and-noise ratio threshold gamma s, an eavesdropping user signal-to-interference-and-noise ratio limit gamma e, the maximum transmitting power Pmax of the base station and the maximum interference power of the base station to the primary user in the satellite-ground fusion cognitive network; step c, establishing two optimization problems of secondary user reachable safety rate maximization and base station transmitting power minimization; step d, establishing a multi-objective optimization problem by adopting a weighted Chebyshev method; and step e, solving a transmitting beam forming weight vector of the base station and an applied artificial noise vector by adopting continuous convex estimation, Taylor series expansion and an interior point method. According to the robust security beam forming method based on multi-objective optimization provided by the invention, compromise between maximization of the reachable security rate and minimization of the transmitting power of the base station can be realized, so that the physical layer security transmission performance of a satellite-ground fusion cognitive network is effectively improved.

Description

technical field [0001] The invention relates to a robust safety beamforming method based on multi-objective optimization, which belongs to the technical field of communication. Background technique [0002] Satellite communication has the advantages of long transmission distance, wide coverage, not limited by geographical conditions, and high-speed data transmission. It has been widely used in many fields such as broadcasting, navigation, national defense, rescue and disaster relief. However, shadowing effects are caused when there are obstacles between the satellite and ground users. The shadowing effect is especially severe when the satellite elevation angle is low or when the user is indoors. In order to solve this problem, someone proposed a satellite-ground fusion cognitive network communication system. In this system, ground terminals receive satellite signals through ground relays. However, the inherent broadcast nature of satellite communication makes the signal e...

AI Technical Summary

Problems solved by technology

However, the inherent broadcast nature of satellite communication makes the signal extremely easy to be eavesdropped by illegal users during the communication process, which leads to the inability to guarantee the physical layer security performance of the satellite-ground fusion cognitive network.

At the same time, there is no compromise between the maximization of the achievable security rate of the satellite-ground fusion cognitive network and the minimization of the base station transmission power

Images