PUCCH Repetition Parameter for Random Access Feedback Reliability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In wireless communication systems, the base station often struggles to receive and decode feedback information from user equipment (UE) during random access procedures, leading to unreliable communication and high latency.
Innovation Solution
The UE determines a Physical Uplink Control Channel (PUCCH) repetition parameter based on the random access message, allowing it to transmit multiple repetitions of feedback information on the PUCCH. This parameter can be configured by the base station via system information or indicated in the random access message.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the UE transmits feedback information using a single PUCCH transmission, then the device complexity is low, but the reliability of feedback transmission is poor
Solution Approach 1:
The feedback transmission is segmented into multiple PUCCH repetitions instead of a single transmission. The UE transmits the same feedback information across multiple PUCCH instances with different repetition factors (e.g., 1, 2, 4, or 8 repetitions), allowing the base station to successfully decode the feedback by combining multiple transmissions, thereby improving reliability without significantly increasing device complexity
Solution Approach 2:
The PUCCH repetition factor is made dynamic rather than fixed. The base station configures multiple PUCCH repetition factors and dynamically selects and indicates the appropriate repetition factor to the UE through DCI messages based on current channel conditions and feedback importance, allowing the system to adapt reliability and complexity to actual needs
2Adaptability or versatility
If the base station configures multiple PUCCH repetition parameters, then the adaptability of the system is improved, but the device complexity increases
Solution Approach 1:
Instead of configuring all possible PUCCH parameters extensively, the system implements partial configuration by providing a limited set of predefined PUCCH repetition factors (e.g., 1, 2, 4, 8) that cover most practical scenarios. The base station selects from this predefined set rather than allowing arbitrary parameter values, achieving sufficient adaptability while limiting configuration complexity
Solution Approach 2:
The UE autonomously determines the appropriate PUCCH repetition factor based on the base station's indication in the DCI message without requiring complex negotiation or additional signaling. The UE simply applies the indicated repetition factor from the configured set, making the system adaptable while keeping both base station and UE implementation relatively simple
Data Source
AI summary
Methods, systems, and devices for wireless communication are described. A communication device, such as a user equipment (UE) may receive, from a network entity, a random access message of a random access procedure, which may be a two-step random access channel (RACH) procedure or a four-step RACH procedure. In some examples, the UE may receive the PUCCH repetition parameter via a physical downlink control channel (PDCCH). Alternatively, the UE may receive the PUCCH repetition parameter via a physical downlink shared channel (PDSCH). The UE may determine a physical uplink control channel (PUCCH) repetition parameter based on the received random access message, and may transmit, to the network entity, feedback information on a PUCCH based on the determined PUCCH repetition parameter.