Two-Step Random Access for HARQ Feedback Resource Allocation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing wireless communication networks face challenges in achieving high traffic capacity and low latency during the random access procedure, particularly in large cells where timing advance is needed, leading to inefficiencies in connection establishment.
Innovation Solution
A two-step random access procedure is introduced, allowing a terminal device to transmit a RA preamble together with higher layer data on the physical uplink shared channel and receive a response message containing both MAC and higher layer parts, optimizing resource allocation for multiple feedbacks to enhance transmission efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of time
If a traditional four-step random access procedure is used, then the connection establishment is more reliable, but the latency is higher and traffic capacity is lower
Solution Approach 1:
The patent segments the random access procedure into two distinct steps: Step 1 where the terminal transmits preamble and data simultaneously, and Step 2 where the network transmits response and retransmission opportunities. This segmentation enables parallel processing of authentication and data transmission, reducing latency while maintaining reliability through structured feedback mechanisms.
Solution Approach 2:
In Step 1, the terminal performs preliminary actions by transmitting both the preamble and data simultaneously, establishing connection parameters before receiving the full response. This preliminary action reduces the overall time needed for connection establishment by overlapping authentication and data transmission operations.
2Reliability
If timing advance is applied in large cells, then the signal synchronization is improved, but the resource allocation efficiency deteriorates
Solution Approach 1:
The patent applies timing advance as a preliminary action in Step 1, where the terminal transmits the preamble before the data on the PUSCH. This allows the network to establish timing synchronization early, enabling efficient resource allocation in subsequent steps without compromising signal synchronization in large cells.
3Measurement precision
If multiple feedbacks are transmitted separately, then the feedback accuracy is improved, but the transmission efficiency deteriorates
Solution Approach 1:
The patent merges multiple feedback transmissions into a single integrated feedback message in Step 2. The network transmits both the random access response and retransmission opportunities together, maintaining feedback accuracy while significantly improving transmission efficiency by reducing the number of separate communication rounds.
Solution Approach 2:
The feedback message in Step 2 serves multiple functions simultaneously: it provides the random access response, indicates retransmission opportunities, and establishes connection parameters. This multi-functionality eliminates the need for separate feedback transmissions, improving overall transmission efficiency without sacrificing feedback accuracy.
Data Source
Figure 1A~1B
Figure 2A~2C
Figure 2D~3A
AI summary
Various embodiments of the present disclosure provide a method for random access. The method which may be performed by a terminal device comprises receiving resource configuration information from a network node. The method further comprises determining an uplink resource for a feedback to a response message from the network node in a two-step random access procedure, based on the received resource configuration information.