Non-Codebook UL MIMO SRS Configuration for Beamforming Delay
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current wireless communication systems, particularly in 5G networks, face inefficiencies in beamforming measurements for user equipment (UE) due to the need to 'sweep' through multiple receiver beams to determine the best beam for a given base station's transmission, leading to significant delay and resource inefficiency.
Innovation Solution
The proposed method involves UE signaling capability information for non-codebook uplink transmissions, allowing the network to configure and determine sounding reference signal (SRS) resources based on this information, enabling efficient precoding for uplink transmissions without requiring simultaneous use of all precoding candidates.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the UE sweeps through multiple receiver beams to determine the best beam for base station transmission, then measurement accuracy is improved, but measurement delay increases and resource efficiency deteriorates
Solution Approach 1:
The network pre-configures multiple SRS resources with different precoding candidates before the UE performs beamforming measurements. This allows the UE to have measurement results ready for multiple beams in advance, eliminating the need to sweep through beams sequentially when a beam change is needed, thus reducing measurement delay while maintaining accuracy
Solution Approach 2:
The system dynamically selects which pre-configured SRS resources to use based on current channel conditions and transmission requirements. The UE determines precoding for uplink transmissions by selecting from pre-configured precoding candidates associated with different SRS resources, allowing flexible adaptation without re-sweeping all beams
2Measurement precision
If the UE sweeps through multiple receiver beams to determine the best beam, then measurement accuracy is improved, but resource efficiency deteriorates
Solution Approach 1:
Multiple SRS resources with different precoding candidates are pre-configured and prepared in advance. The UE performs measurements on these pre-configured resources, having measurement results ready without needing to sweep through all beams when transmission needs to occur, thus improving resource efficiency while maintaining measurement accuracy
Solution Approach 2:
The UE autonomously determines which pre-configured precoding candidates to use based on the received SRS resource indications from the network. This self-service capability allows the UE to efficiently select appropriate precoding without requiring network coordination for each beam selection, improving overall resource efficiency
3Adaptability or versatility
If all precoding candidates are configured for the UE, then transmission flexibility is improved, but device complexity increases
Solution Approach 1:
Instead of configuring all possible precoding candidates, the network configures a selective subset of SRS resources with precoding candidates based on UE capability information and current transmission requirements. This partial configuration approach maintains sufficient transmission flexibility while reducing UE complexity by avoiding the need to process and manage all possible precoding options
Data Source
AI summary
Aspects of the present disclosure relate to techniques for non-codebook based uplink (UL) transmission. In some cases, a user equipment (UE) may signal, to a network entity, capability information of the UE for non-codebook uplink transmissions. The UE may then receive, signaling, from the network entity, indicating a plurality of sounding reference signal (SRS) configurations based at least on the signaled capability information, wherein at least one configuration indicates at least one SRS resource and determine a plurality of precoding candidates, wherein each precoding candidate is associated with a configured SRS resource. The UE may then transmit the SRSs using the associated precoding candidates.