RACH Resource Identification in 5G NR User Equipment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In 5G NR radio communication systems, the signaling overhead is large when indicating available RACH resources and their configurations to user equipment for initial access, due to the need to specify locations in both time and frequency domains, and the flexibility of DL/UL assignment.
Innovation Solution
User equipment is equipped with a receiver to receive information on a RACH configuration table and a control unit to identify available RACH resources based on this information, allowing for efficient indication of resources using a transmitter to send a preamble with the identified resource, where the information includes an unknown region that can be used for either downlink or uplink.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If all information for identifying RACH resources (locations in time and frequency domains, preamble index, associated SS block) is indicated to user equipment, then user equipment can accurately identify available RACH resources, but signaling overhead becomes large
Solution Approach 1:
The patent extracts only the essential information needed for RACH resource identification from the complete set of parameters. Instead of signaling all possible information (time domain locations, frequency domain locations, preamble indices, SS block associations), the invention selectively transmits only the critical subset required for accurate identification, thereby reducing signaling overhead while maintaining identification accuracy.
Solution Approach 2:
The patent creates a universal RACH resource identification mechanism that can work with different configurations without requiring separate detailed signaling for each case. By establishing a standardized mapping relationship between SS blocks and RACH resources that works across multiple scenarios, the system achieves multi-functionality with reduced signaling requirements.
2Adaptability or versatility
If DL or UL is flexibly set to the symbol of the slot that constitutes the radio frame, then the system can adapt to different communication scenarios, but determining available RACH resources becomes more complex
Solution Approach 1:
The patent performs preliminary determination of RACH resource availability based on pre-configured rules and previously received configuration information. By establishing determination criteria in advance that account for flexible DL/UL assignments, the system enables user equipment to autonomously identify available RACH resources without requiring complex real-time analysis, thus reducing operational complexity while maintaining adaptability.
Solution Approach 2:
The patent implements a dynamic RACH resource determination mechanism that automatically adapts to different DL/UL assignment configurations. The system uses predefined rules that dynamically adjust based on the actual DL/UL pattern, allowing flexible adaptation to various communication scenarios without increasing device complexity through manual configuration or complex algorithms.
Data Source
AI summary
User equipment for communicating with a base station via a radio frame includes a receiver to receive, from the base station, information indicating a downlink region or an uplink region, and information on a RACH configuration table indicating allocation of RACH resources associated with a time domain; a control unit to identify an available RACH resource, based on the information indicating a downlink region or an uplink region, and the information on the RACH configuration table; and a transmitter to transmit a preamble to the base station using the identified available RACH resource. The information indicating the downlink region or the uplink region includes an unknown region used for one of downlink and uplink, and availability of the RACH resource in the unknown region is explicitly or implicitly identified in case where the information on the RACH configuration table indicates that the RACH resource is allocated to the unknown region.