MU MIMO Precoder Generation via Adaptive Matrix Inversion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In multi-user multiple input and multiple output (MU MIMO) communication systems, the condition number of the spatial channel can lead to high packet error rates due to large singular value differences, resulting in poor communication quality when all streams support the same modulation and coding scheme.
Innovation Solution
A method for generating a precoder that involves receiving channel and quality information from multiple stations, determining the number of streams, and selecting appropriate matrix inversion or decomposition types based on interference canceling capability and quality information to reduce packet errors and improve communication reliability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If the same modulation and coding scheme is supported for each stream, then system simplicity is maintained, but packet error rate increases due to large singular value differences
Solution Approach 1:
The patent applies local quality by allowing different modulation and coding schemes (MCS) to be assigned to different streams based on their individual channel conditions. Specifically, the system determines MCS for each stream separately based on singular value information, enabling optimal error performance for each stream while maintaining overall system performance. This resolves the contradiction by moving from a uniform MCS approach to a stream-specific MCS assignment.
2Reliability
If rank reduction is performed to improve reliability, then packet error rate decreases, but data transmission efficiency is reduced
Solution Approach 1:
The patent applies parameter changes by dynamically adjusting the rank parameter based on channel conditions and singular value distribution. The system determines an optimal rank that balances reliability and efficiency by evaluating singular value differences and selecting a rank that provides sufficient error performance while maximizing the number of transmitted streams. This allows the system to adapt the rank parameter to achieve optimal trade-off between packet error rate and data transmission efficiency.
3Productivity
If multiple streams are allocated to improve data rate, then productivity increases, but interference between streams increases causing higher error rates
Solution Approach 1:
The patent applies local quality by determining modulation and coding schemes independently for each stream based on its specific channel quality and singular value. This allows the system to allocate multiple streams to increase data rate while assigning appropriate MCS to each stream to compensate for inter-stream interference. Streams with higher singular values can use higher-order modulation, while streams with lower singular values use more robust coding, thereby maintaining reliability despite increased productivity.
Data Source
AI summary
Provided is method for generating a precoder in a Multi User Multiple Input and Multiple Output (MU MIMO) communication system. The method involves receiving channel information and quality information of a channel from a plurality of stations. It is determined whether a first condition is satisfied on the basis of the received information, if so, a type of matrix inversion is selected from among a plurality of matrix inversion types for precoding. It is determined whether a second condition is satisfied on the basis of the provided information, and a type of decomposition from a plurality of decomposition types for precoding is selected if the second condition is satisfied. A precoder is generated on the basis of the selected result.