HARQ Process ID Mapping for Satellite Network Latency
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing HARQ procedures in LTE/NR are not well suited for satellite-based networks due to large propagation delays, leading to reduced throughput and inefficiencies in HARQ processes.
Innovation Solution
Implementing methods for mapping data to specific HARQ process IDs, enabling/disabling HARQ feedback, and using bundling techniques to optimize communication reliability and efficiency in non-terrestrial networks.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If existing HARQ procedures in LTE/NR are used for satellite-based networks, then the standard protocol compatibility is maintained, but the throughput is reduced and HARQ process efficiency deteriorates due to large propagation delays
Solution Approach 1:
The patent segments the HARQ process management by introducing separate HARQ process ID spaces for different satellite beams or cells. This allows independent management of HARQ processes in each beam, enabling parallel processing and reducing the impact of propagation delays on overall system throughput. Each beam can maintain its own HARQ timeline, preventing delays in one beam from affecting others.
Solution Approach 2:
The patent implements dynamic HARQ process ID mapping where the mapping between logical channel data and HARQ process IDs can be adjusted based on propagation delay conditions. The system can dynamically configure the number of HARQ processes and their mapping relationships to adapt to varying satellite beam conditions, optimizing throughput under different delay scenarios.
2Reliability
If the number of HARQ processes is increased to handle large propagation delays, then the coverage and reliability are improved, but the device complexity and processing overhead increase
Solution Approach 1:
The patent applies local quality by configuring different numbers of HARQ processes for different beams or cells based on their specific propagation delay characteristics. Instead of uniformly increasing HARQ processes across the entire system, each beam can be optimized independently, maintaining reliability where needed while avoiding unnecessary complexity in other areas.
Solution Approach 2:
The patent creates equipotentiality by establishing consistent HARQ process management rules and mapping mechanisms across different beams. This standardized approach ensures that all beams handle HARQ processes in a uniform manner, simplifying overall system management while maintaining reliability through appropriate process counts in each beam.
3Reliability
If HARQ feedback is continuously transmitted to ensure reliable data transmission, then the communication reliability is improved, but the latency and processing overhead increase
Solution Approach 1:
The patent implements periodic action by organizing HARQ feedback transmission in structured time intervals and slots. Feedback is transmitted at predetermined periodic intervals rather than continuously, which maintains reliability through regular acknowledgment while reducing overall latency and processing overhead compared to continuous feedback mechanisms.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A method performed by a wireless device for mapping data to specific HARQ processes is provided. The method includes receiving (704) an indication that maps data that can be sent on one or more of specific HARQ processes and transmitting (706) a transmission for the specific HARQ process based on the received indication. A corresponding method performed by a base station is also provided. A corresponding wireless device and a corresponding base station are also provided.