Sky wave large-scale MIMO communication downlink transmission method

Abstract

The invention discloses a sky-wave large-scale MIMO (Multiple Input Multiple Output) communication downlink transmission method, which comprises the following steps that: sky-wave large-scale MIMO communication adopts a beam-based channel statistical model which is expressed as a product of a beam matrix and a beam domain channel vector; the method comprises the following steps: at a base station side, generating a non-zero beam index set of each user and a multi-user non-zero beam index set by using statistical information and sparse characteristics of beam domain channels, and obtaining a dimensionality reduction beam domain channel, dimensionality reduction beam domain statistical channel information and a dimensionality reduction beam matrix of each user; at a base station side, optimal design or asymptotically optimal design of a user downlink precoding matrix is carried out in a dimensionality reduction beam domain, and then the obtained user downlink precoding matrix is utilized to generate a user downlink sending signal through precoding. According to the method, the spectrum efficiency of sky wave communication in a high-speed mobile scene can be remarkably improved, so that the transmission rate and the transmission distance are greatly improved, and meanwhile, the problem that a related large-dimensional downlink precoding matrix is complex in design is solved.

Description

technical field [0001] The invention relates to the field of sky wave communication, in particular to a downlink transmission method related to sky wave massive MIMO communication. Background technique [0002] Sky-wave communication usually works in the short-wave band with a carrier frequency of 1.6-30MHz, and can realize long-distance signal transmission through ionospheric reflection without expensive ground infrastructure. Traditional sky-wave communication systems often rely on a single-input-single-output system architecture, which has very low system capacity. Massive MIMO technology can serve a large number of users on the same time-frequency resource by configuring an array composed of a large number of antennas on the base station side. It is an important potential enabling technology for sky-wave broadband communications in the future. [0003] Generally speaking, the accuracy of user downlink channel state information available at the base station side has a co...

AI Technical Summary

Problems solved by technology

In the existing literature, the covariance matrix design of downlink transmission signals based on statistical channel information often uses the channel model established by discrete Fourier transform, and does not fully consider the angular domain sparse characteristics of massive MIMO channels

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