Beam-Specific RACH Configuration for Variable RTT Resource Efficiency
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing wireless communication systems face inefficiencies in random access channel (RACH) configuration due to varying round-trip time (RTT) values across different beam directions, leading to excessive monitoring and inefficient energy/spectral resource usage, particularly in scenarios with repeaters or non-uniform cell coverage.
Innovation Solution
Configuring beam-specific and/or user-specific RACH configurations, including beam-specific timing advance (TA) offsets, to accommodate varying RTT values and optimize resource usage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If a single RACH configuration is used for all beam directions, then device complexity is reduced and ease of operation is improved, but spectral efficiency and energy efficiency deteriorate due to excessive monitoring and inability to accommodate varying RTT values
Solution Approach 1:
The patent segments the unified RACH configuration into multiple beam-specific configurations, where each configuration is tailored to the RTT characteristics of its corresponding beam direction. This allows the system to accommodate varying RTT values without requiring a single conservative configuration that forces excessive monitoring across all beams.
Solution Approach 2:
The patent applies local quality by assigning different RACH configuration parameters (such as monitoring occasions and timing advance values) to different beam directions based on their local RTT characteristics. This ensures that each beam direction uses monitoring resources appropriate to its specific propagation conditions, avoiding both excessive and insufficient monitoring.
2Loss of energy
If beam-specific RACH configurations are implemented, then spectral efficiency and energy efficiency are improved, but device complexity and configuration complexity increase
Solution Approach 1:
The patent changes key RACH parameters (monitoring occasions, timing advance offsets, preamble formats) on a beam-specific basis to match varying RTT characteristics. By selectively modifying these parameters rather than redesigning the entire RACH procedure, the patent achieves efficiency improvements while limiting the growth of configuration complexity.
Solution Approach 2:
The patent introduces dynamic beam-specific timing advance mechanisms that allow UEs to adjust their RACH timing based on measured RTT values for specific beam directions. This dynamic adaptation enables the system to respond to changing propagation conditions without requiring static complex configurations for all possible scenarios.
3Reliability
If conservative RACH monitoring is used to accommodate maximum RTT values, then reliability is improved, but spectral efficiency deteriorates due to excessive monitoring occasions and resource usage
Solution Approach 1:
The patent applies local quality by configuring monitoring occasions and timing parameters specifically matched to the RTT characteristics of each beam direction. This ensures that reliability is maintained for each local condition without forcing all UEs to use conservative monitoring schedules that waste spectral resources in beams with smaller RTT variations.
Solution Approach 2:
The patent changes monitoring-related parameters (monitoring occasion periods, timing advance ranges, preamble transmission timing) based on beam-specific RTT measurements. This allows the system to reduce monitoring overhead in beams with stable, small RTT variations while maintaining adequate monitoring in beams with larger variations, thus improving overall spectral efficiency without compromising reliability.
Data Source
AI summary
Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may receive information identifying a set of random access channel (RACH) configurations, wherein a RACH configuration, of the set of RACH configurations, is at least one of: specific to the UE and applicable to a subset of beam directions of a set of beam directions, or specific to a beam. The UE may transmit a RACH message in accordance with the RACH configuration. Numerous other aspects are described.