Grant-Free Uplink Coexistence via Frequency Partitioning
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current wireless networks face challenges in efficiently coexisting grant-free and grant-based uplink traffic due to overlapping resource allocation and potential collisions, which affect latency and reliability in transmissions.
Innovation Solution
The method involves scheduling uplink grant-based traffic in a first frequency partition and mapping UEs for grant-free transmission to non-overlapping time-frequency regions in a second frequency partition, allowing for initial and retransmission overlap while minimizing collisions through distinct time-frequency region assignments and varying transmission unit durations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If grant-free and grant-based traffic share the same frequency resources, then resource utilization efficiency is improved, but collision probability increases and transmission reliability deteriorates
Solution Approach 1:
The frequency spectrum is segmented into multiple partitions, with different partitions allocated to grant-free and grant-based traffic. This spatial segmentation in the frequency domain allows both traffic types to coexist without collisions, resolving the contradiction between resource utilization and transmission reliability.
Solution Approach 2:
The patent introduces frequency partitioning as an additional dimension for resource allocation. By dividing the frequency spectrum into multiple non-overlapping partitions, the system enables grant-free and grant-based traffic to operate in different frequency dimensions simultaneously, eliminating collisions while maintaining high resource utilization.
2Reliability
If grant-free traffic uses dedicated time-frequency resources, then transmission reliability is improved, but resource flexibility and utilization efficiency worsen
Solution Approach 1:
Different quality levels of resource allocation are applied to different traffic types: grant-free traffic receives dedicated, high-reliability resources in specific frequency partitions, while grant-based traffic uses dynamically allocated resources in other partitions. This local quality differentiation ensures reliability for grant-free traffic while maintaining flexibility for grant-based traffic.
3Productivity
If multiple UEs are mapped to the same grant-free resources, then resource efficiency is improved, but collision probability increases and latency increases
Solution Approach 1:
The system segments frequency resources into multiple partitions and assigns different grant-free UEs to different partitions. This segmentation reduces the number of UEs sharing the same resources, thereby reducing collision probability and latency while maintaining reasonable resource efficiency through the overall frequency division multiplexing.
Data Source
AI summary
Systems and methods of scheduling grant-based traffic and mapping resources for grant-free traffic are provided. Grant-based traffic is scheduled in a first frequency partition, and grant-free traffic is mapped in a second frequency partition. In a first option, grant-based traffic is also scheduled in part of the first partition, but in a limited manner that ensures a given device's transmission and retransmissions do not all experience interference with the grant-based traffic. In another option, some grant-free traffic is mapped to part of the second partition and is spread in frequency across the second partition.