Random Access Preamble Resource Allocation for Multi-Beam NR Systems
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In 3GPP NR systems, existing methods for random access procedures face challenges in supporting both single-beam and multi-beam operations, particularly in determining optimal RA preamble formats and resources for efficient message transmission and reception, especially when beam correspondence is uncertain or fails.
Innovation Solution
The method involves determining a first RA preamble resource corresponding to a synchronization signal block index and transmitting a message using a RA preamble format that includes the first resource and neighboring resources, with an optional guard time, cyclic prefix, and OFDM symbols, allowing for long or short preamble formats based on cell coverage, and re-transmitting using longer formats if necessary.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If beam sweeping scheme is used for multi-beam operation, then system performance is enhanced, but device complexity increases
Solution Approach 1:
The RA preamble format is segmented into multiple RA preamble resources, each associated with a specific SSB index and transmission beam. This segmentation allows the system to handle multi-beam operations by dividing the preamble transmission into discrete, manageable resources, reducing the complexity of managing beam correspondence while maintaining enhanced system performance through structured resource allocation.
2Productivity
If multiple RA preamble resources are included in RA preamble format, then random access message transmission is optimized, but signal length increases
Solution Approach 1:
The RA preamble format dynamically adapts its structure by including multiple RA preamble resources corresponding to different SSB indexes. This dynamic configuration allows the system to optimize random access message transmission by selecting appropriate preamble resources based on beam correspondence conditions, while the associated control information efficiently manages the variable signal length without excessive overhead.
3Adaptability or versatility
If RA preamble resources are associated with SSB indexes, then beam correspondence is supported, but device complexity increases
Solution Approach 1:
The system implements feedback mechanisms where the RA preamble resources are explicitly associated with SSB indexes, enabling the receiving end to determine which transmission beam was used. This feedback loop supports beam correspondence by allowing the system to identify and respond to specific beams, while the structured association between preamble resources and SSB indexes provides a systematic approach that manages device complexity through organized resource mapping.
Data Source
AI summary
A method and an apparatus for transmitting a message used to access a base station (BS) in a random access (RA) procedure by user equipment (UE) are provided. The method includes: determining a first RA preamble resource corresponding to an SSB index which corresponds to a transmission beam among a plurality of transmission beams of BS; and transmitting a message 1 of the RA procedure by using a first RA preamble format which includes the first RA preamble resource and at least one second RA preamble resource which neighbors the first RA preamble resource.