Random Access Preamble Transmission via Multi-Carrier Idle Resource Selection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In 5G unlicensed spectrum communication, the Listen Before Talk (LBT) mechanism increases time delay and reduces efficiency of random access due to the need to monitor channels for available time-frequency resources before sending messages, especially when resources are not readily available.
Innovation Solution
Configuring multiple carriers for monitoring and transmitting random access channels, allowing for the selection of idle time-frequency resources for transmission, thereby improving the probability of successful transmission and reducing time delay.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If LBT mechanism is implemented to monitor channels before sending messages, then channel access reliability is improved, but time delay increases and random access efficiency deteriorates
Solution Approach 1:
The patent segments the monitoring process by dividing it into two distinct stages: initial channel assessment (LBT) and final transmission opportunity confirmation. This segmentation allows the system to perform lightweight initial checks quickly, then only perform full monitoring when resources are actually needed, thereby reducing overall time delay while maintaining reliability
Solution Approach 2:
The patent applies preliminary action by performing initial channel assessment and resource selection before the actual random access transmission. The user equipment pre-identifies suitable time-frequency resources and performs preliminary LBT checks, so that when transmission is needed, the channel is already prepared and validated, reducing the time required at the critical transmission moment
2Productivity
If single carrier is used for PRACH transmission, then device complexity is reduced, but random access efficiency deteriorates due to lower probability of finding idle resources
Solution Approach 1:
The patent implements multi-functionality by configuring multiple carriers for PRACH transmission, where each carrier can serve as a potential transmission resource. This allows the system to universally handle random access requests across multiple frequency resources, increasing the probability of finding idle resources and improving random access efficiency
Solution Approach 2:
The patent transitions from a single-dimension (single carrier) approach to a multi-dimensional approach by introducing multiple carriers across different frequency resources. This dimensional expansion allows the system to search for available resources not just in time domain but also in frequency domain, significantly improving the likelihood of successful random access
Data Source
AI summary
The present invention relates to a random access processing method and apparatus. The method includes: monitoring, on at least one carrier in a pre-configured first carrier group, whether a time-frequency resource for transmitting a physical random access channel (PRACH) is idle, wherein the first carrier group comprises at least two carriers; and when there is an idle time-frequency resource for the PRACH, sending a random access preamble on the idle time-frequency resource for the PRACH to request random access.