Uplink Precoding Group Size Control for Radio Terminal
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In future radio communication systems, the use of different access schemes like OFDMA for uplink signals leads to varying frequency characteristics across bands, resulting in suboptimal multi-antenna transmission gains and deteriorated receiving characteristics due to the application of a single precoding matrix across the entire frequency band.
Innovation Solution
A user terminal is designed to transmit uplink signals precoded per precoding group, with the control section managing the size of these groups in the frequency direction, allowing for the application of different precoding matrices within each group to improve receiving characteristics.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a single precoding matrix is applied to the entire frequency band, then device complexity is reduced, but receiving characteristics deteriorate due to varying frequency characteristics across bands
Solution Approach 1:
The frequency band is divided into multiple precoding groups (PRGs), allowing different precoding matrices to be applied to different frequency segments. This segmentation enables the system to adapt to varying frequency characteristics across bands while maintaining manageable complexity through standardized group configurations.
Solution Approach 2:
Different precoding matrices are applied to different precoding groups based on their specific frequency characteristics. Each group can be optimized independently for its local frequency properties, improving overall receiving characteristics without requiring unique optimization for every individual resource block.
2Reliability
If different precoding matrices are applied per precoding group, then receiving characteristics improve, but device complexity increases due to multiple precoding configurations
Solution Approach 1:
The system dynamically selects appropriate precoding matrices for each precoding group based on channel conditions and frequency characteristics. The control section adapts the precoding configuration in real-time, allowing the system to optimize receiving characteristics while managing complexity through intelligent selection rather than exhaustive configuration.
Solution Approach 2:
The invention changes the precoding parameters (precoding matrices) according to the frequency group index and channel conditions. By systematically varying precoding parameters across different precoding groups rather than using a fixed configuration, the system improves receiving characteristics while maintaining controlled complexity through parameterized configurations.
3Ease of manufacture
If the same precoding matrix is used across all frequency bands, then implementation simplicity is maintained, but multi-antenna transmission gains cannot be effectively achieved
Solution Approach 1:
The frequency band is segmented into multiple precoding groups, each capable of using optimized precoding matrices for multi-antenna transmission. This segmentation enables effective exploitation of spatial multiplexing gains in each frequency segment while maintaining implementation simplicity through standardized group structures and systematic matrix selection.
Data Source
AI summary
A terminal is disclosed that includes a transmitter that transmits an uplink (UL) signal which is precoded per precoding group that includes a given number of frequency resource units; and a processor that controls precoding of the UL signal. The processor determines a size of the precoding group of the UL signal based on a downlink signal (DL) signal. In other aspects, a radio communication method is also disclosed.