MIMO Precoding Matrix Superposition for Signal Quality
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Solution Overview
Problem
In multiple-input multiple-output (MIMO) wireless communication systems, direct superposition of high-power and low-power signal streams on the same antennas leads to wastage of antenna resources and decreased signal quality, as user terminals can only demodulate one combined signal stream.
Innovation Solution
A method where a base station obtains high-power and low-power precoding matrices based on channel quality information, precodes the corresponding signal streams, and superimposes them in different manners for transmission to user terminals at the edge and center of a cell, respectively, allowing for efficient power allocation and improved Signal-to-Interference-plus-Noise Ratio (SINR) and mean-square error performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If high-power and low-power signal streams are directly superimposed on the same antennas in the same superimposing manner, then the transmission process is simple, but antenna resources are wasted and signal receiving quality decreases
Solution Approach 1:
The patent segments the signal transmission process by applying different precoding matrices to high-power and low-power signal streams. Specifically, a first precoding matrix is applied to the high-power signal stream and a second precoding matrix is applied to the low-power signal stream before superposition, allowing differentiated processing that optimizes signal quality for different user types without complicating the overall transmission architecture
Solution Approach 2:
The patent implements local quality by tailoring the precoding strategy to specific signal stream characteristics and user requirements. High-power signals intended for cell-edge users receive one precoding matrix optimized for their channel conditions, while low-power signals for cell-center users receive a different precoding matrix, thereby optimizing the local signal quality for each user group rather than applying a uniform approach
2Reliability
If different precoding matrices are applied to high-power and low-power signal streams, then signal receiving quality is enhanced, but the calculation complexity increases
Solution Approach 1:
The patent applies preliminary action by pre-calculating and storing multiple precoding matrices before actual signal transmission. The base station maintains a codebook of candidate precoding matrices and selects appropriate matrices in advance based on channel quality information, avoiding the need for complex real-time calculations during signal transmission and reducing instantaneous computational burden
Solution Approach 2:
The patent implements feedback mechanisms where user terminals report channel quality information back to the base station. This feedback enables the base station to select appropriate precoding matrices from pre-calculated options, creating a closed-loop system that adapts to channel conditions without requiring complex real-time matrix calculations, thereby balancing signal quality enhancement with computational complexity
Data Source
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AI summary
Embodiments of the present invention provide a method, an apparatus, and a system for signal transmission. The method includes: obtaining, by a base station, a high-power precoding matrix and a low-power precoding matrix according to channel quality information, precoding a corresponding high-power signal stream according to the high-power precoding matrix respectively to obtain a first signal stream, precoding a corresponding low-power signal stream according to the low-power precoding matrix respectively to obtain a second signal stream, superimposing the first signal stream and the second signal stream to obtain one or more superimposed signal streams and transmitting the one or more superimposed signal streams to user terminals; decoding, by the user terminals, the received one or more superimposed signal streams by using receiving matrices, and obtaining signal streams that the user terminals need. The embodiments of the present invention are applicable to signal transmission in a Multiple-Input Multiple-output system.