Uplink Transmission Adaptation After PUSCH Misdetection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In 5G NR wireless networks, when an expected uplink transmission from user equipment (UE) fails, repeatedly transmitting new grants with the same parameters often results in unsuccessful transmissions until the call fails.
Innovation Solution
A cellular base station (gNB) in a 5G NR wireless network adjusts the downlink control information (DCI) by changing the Aggregation Level (AL) and/or modifying the uplink grant to increase the likelihood of successful uplink transmissions from the UE.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the cell base station transmits a new grant with exactly the same parameters as the one that failed to receive a response, then the transmission parameters remain consistent and predictable, but the uplink transmission success rate decreases significantly
Solution Approach 1:
The base station changes one or more parameters of the uplink grant (such as resource blocks, modulation and coding scheme, transmit power) when retransmitting after a failed uplink transmission. This parameter adaptation allows the system to overcome the initial transmission failure by adjusting to different channel conditions, thereby improving the success rate of subsequent uplink transmissions.
2Reliability
If the base station adjusts the Aggregation Level (AL) and/or grant parameters to increase transmission success probability, then the uplink transmission reliability improves, but the downlink control information complexity increases
Solution Approach 1:
The base station dynamically adjusts the Aggregation Level and grant parameters based on the outcome of previous transmissions. When an uplink transmission fails, the system increases the AL or modifies grant parameters for subsequent transmissions. This dynamic adaptation enables the system to respond to transmission failures in real-time, improving reliability while managing complexity through conditional adjustments rather than constant high-level configurations.
3Device complexity
If the base station repeatedly transmits grants with the same parameters until call failure, then the system maintains simplicity in grant transmission, but the call continuity and user experience deteriorate
Solution Approach 1:
The base station prepares adjusted grant parameters in advance based on the detection of failed uplink transmissions. When a transmission failure is detected, the system has pre-configured alternative parameters ready for immediate use, allowing quick adaptation without complex real-time calculations. This preliminary preparation maintains operational simplicity while ensuring call continuity by having fallback options ready.
Data Source
AI summary
Disclosed are systems and methods for user equipment (UE) transmission adaptation after physical uplink shared channel (PUSCH) misdetection. Instead of the cell base station (e.g., gNB) transmitting a new grant with exactly the same parameters as a first grant transmission that failed to receive a response from the user equipment (UE), the gNB transmits a new transmission with an adjusted DCI and/or an adjusted grant to increase a probability that the expected uplink (UL) transmission is received from the UE. For example, a gNB may transmit a new DCI with a new Aggregation Level (AL) indicating a new UL grant to cause one or more of: an increase in UL power spectral density (PSD) on the PUSCH; a reduction in a number of allocated resource blocks (RB); a reduction in transport block size (TBS); a reduction in a Modulation and Coding Scheme (MCS) to use for the UE transmission; and use of different redundancy versions (RV) for retransmissions.