Semi-Persistent Scheduling Signaling Overhead Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current wireless communication systems face inefficiencies in transmission scheduling, particularly in coordinating periodic data transmissions between transmitting nodes and radio nodes, leading to high signaling overhead and potential decoding errors due to the need for frequent Downlink Control Information (DCI) updates.
Innovation Solution
Implementing semi-persistent scheduling (SPS) that allows a transmitting node to instruct a radio node to receive data according to the same DCI each period, with the option to switch between dynamic and semi-persistent scheduling modes, reducing signaling overhead by configuring periodicity in terms of time or subframes, and managing Hybrid Automatic Repeat Request (HARQ) acknowledgments and negative acknowledgments accordingly.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If dynamic scheduling with frequent DCI updates is used, then transmission coordination is achieved, but signaling overhead increases
Solution Approach 1:
The patent implements semi-persistent scheduling where DCI is transmitted periodically at predefined intervals rather than dynamically for each transmission. This periodic action reduces signaling overhead by eliminating the need for frequent DCI updates while maintaining transmission coordination through the established periodic schedule.
Solution Approach 2:
The transmitting node preliminarily configures the radio node with semi-persistent scheduling parameters including periodicity, resource allocation, and DCI format before actual data transmissions begin. This preliminary configuration enables the radio node to autonomously decode periodic transmissions without requiring continuous DCI updates, thereby reducing signaling overhead while maintaining reliable coordination.
2Quantity of substance
If semi-persistent scheduling with same DCI each period is used, then signaling overhead is reduced, but adaptability to changing conditions decreases
Solution Approach 1:
The patent enables dynamic switching between dynamic scheduling and semi-persistent scheduling modes based on channel conditions, traffic patterns, and other system parameters. This dynamic adaptability allows the system to utilize semi-persistent scheduling for stable periodic traffic to reduce overhead, while switching to dynamic scheduling when rapid adaptation to changing conditions is required, thereby balancing overhead reduction with scheduling flexibility.
3Productivity
If HARQ feedback is reduced for periodic transmissions, then resource usage is optimized, but error detection capability is weakened
Solution Approach 1:
The patent implements selective HARQ feedback mechanisms where acknowledgment feedback is transmitted only for certain periodic transmissions based on configured conditions, such as every Nth transmission or only when errors are detected. This selective feedback approach optimizes resource usage by reducing the frequency of feedback transmissions compared to traditional HARQ, while maintaining adequate error detection capability through the periodic feedback schedule and redundancy mechanisms inherent in the semi-persistent scheduling configuration.
Data Source
AI summary
A transmitting node (110) transmits a message (210) instructing a radio node (105) that data will be transmitted to the radio node (105) according to the same Downlink Control Information (DCI) each period (250). The message (210) includes a duration of the period (250). The transmitting node (110) further transmits the DCI to the radio node (105) for the periodic transmission (260). The radio node (105) receives the message (210) and the DCI from the transmitting node (110), and decodes each of a plurality of transmissions of the periodic transmission (260) according to the DCI.