Fast Beam Management via TCI State Updates
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing wireless communication systems face challenges in efficiently reporting channel state information for large two-dimensional array transmit antennas, leading to suboptimal beam management and increased latency in 5G communication systems, particularly in high-frequency bands where beamforming and massive MIMO techniques are employed.
Innovation Solution
The implementation of a method for low-latency beam selection in user equipment (UE) and base stations, which involves receiving and transmitting configuration information on transmission configuration indicator (TCI) states, including source reference signals with quasi co-location (QCL), to facilitate efficient beam management and reduce latency by streamlining beam reporting and indication processes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If existing channel quality reporting processes are used for large two-dimensional array transmit antennas, then the system can maintain backward compatibility, but beam management efficiency deteriorates and latency increases
Solution Approach 1:
The patent segments the beam management process into distinct phases: beam indication through TCI state configuration and beam reporting through separate CSI reports. This segmentation allows independent optimization of each phase, enabling faster beam indication without compromising comprehensive channel quality assessment.
Solution Approach 2:
The patent implements preliminary action by pre-configuring TCI states that associate multiple source reference signals with target channels before actual data transmission. This pre-association enables immediate beam application when needed, eliminating the need for real-time beam computation and reducing latency.
2Measurement precision
If comprehensive channel state information reporting is performed for all antenna elements, then measurement precision improves, but device complexity and signaling overhead increase
Solution Approach 1:
The patent extracts the essential beam direction information from comprehensive channel state information by using TCI states that reference specific source signals. Instead of reporting complete channel matrices for all antenna elements, the system extracts and transmits only the critical beam identification data through TCI state indicators.
Solution Approach 2:
The TCI state mechanism serves multiple functions simultaneously: it indicates beam direction, associates source and target channels, and enables both beam indication and beam reporting. This multi-functionality reduces the need for separate signaling mechanisms, thereby decreasing overall system complexity while maintaining measurement precision.
3Speed
If fast beam switching is implemented for high-mobility scenarios, then responsiveness improves, but beam selection accuracy may deteriorate
Solution Approach 1:
The patent prepares multiple TCI states in advance, each associated with different beam directions and source reference signals. During high-mobility scenarios, the system can immediately switch between pre-configured TCI states without requiring real-time beam computation, thus achieving fast beam switching while maintaining accuracy through pre-optimized beam selections.
Solution Approach 2:
The patent implements feedback mechanisms where the UE reports channel quality information based on configured TCI states, and the gNB uses this feedback to select and update appropriate TCI states. This closed-loop feedback ensures that even during fast beam switching in high-mobility scenarios, the selected beams remain accurate based on current channel conditions.
Data Source
AI summary
Methods and apparatuses for fast beam selection. A method for operating a user equipment (UE) includes receiving configuration information on a set of transmission configuration information (TCI) states. Each of the TCI states refers to at least one source reference signal (RS) with a corresponding quasi co-location (QCL) and is associated with downlink (DL) data and UE-specific DL control information (DCI). The method further includes receiving a TCI state update on a physical downlink control channel (PDCCH), decoding the TCI state update, and applying the TCI state update to a reception of DL data and a corresponding UE-specific DL assignment.