Robust precoding method for multi-beam satellite communication system based on interruption probability constraint

Abstract

The invention discloses a robust precoding method for a multi-beam satellite communication system based on interruption probability constraint. Firstly, channel phase uncertainty caused by channel state information feedback delay is represented by a random variable. The robust precoding problem is modelled as a power minimization problem based on interruption probability constraint based on a channel model. Secondly, based on the central limit theorem and the property of Gaussian distribution, a probability constraint condition is converted into a low-complexity approximate representation formconvenient to solve. Finally, an initial power minimization problem is converted into a convex optimization problem through positive semi-definite relaxation, and a Gaussian randomization method is adopted to obtain a precoding vector of each user group. Compared with a traditional transmission method which does not consider the uncertainty of channel information, the robust transmission method based on the interruption probability constraint provided by the invention has the advantages that the transmission interruption probability can be obviously reduced, and the transmission performance of a multi-beam satellite communication system is improved.

Description

technical field [0001] The invention relates to a robust precoding method for a multi-beam satellite communication system based on outage probability constraints. Background technique [0002] Compared with single beam, multi-beam has become the development trend of the next generation mobile satellite communication system due to its significantly improved system throughput. In multi-beam satellites, how to reduce inter-beam interference is an urgent problem to be solved. In order to improve the spectrum efficiency of the system, the traditional frequency reuse method is no longer applicable, and the same-frequency networking has become a research hotspot. In a multi-beam satellite mobile communication system that adopts the same-frequency networking, the purpose of reducing inter-beam interference can be achieved by performing multi-beam joint precoding at the transmitter. [0003] In multi-beam satellite mobile communication systems using DVB-S2 and DVB-S2X, precoding ne...

AI Technical Summary

Problems solved by technology

Compared with the other two, the precoding method based on outage probability constraints ensures more reliable system gain by setting probability thresholds, but because the probability constraints often have no simple closed-form expression and have high computational complexity, Therefore, it is necessary to find a low-complexity approximate form that is easy to solve to represent, and the present invention provides a robust precoding method for multi-beam satellite communication systems based on outage probability constraints

Images