TDD Slot Grouping for Cross-Link Interference Mitigation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Cross-link interference occurs between neighboring cells operating with different TDD configurations, leading to significant interference on cell edges and varying interference patterns due to unsynchronized networks, which limits spectrum utilization and throughput.
Innovation Solution
Grouping TDD slots into categories based on susceptibility to cross-link interference and applying different link adaptation and scheduling strategies for each group to mitigate interference.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If neighboring cells use different TDD configurations to dynamically adapt to traffic patterns, then spectrum utilization and adaptability improve, but cross-link interference increases significantly
Solution Approach 1:
The patent segments TDD slots into two distinct groups: fixed slots and varying slots. Fixed slots are configured identically across all cells to provide interference-free transmission periods, while varying slots allow dynamic configuration adjustments. This segmentation enables cells to achieve dynamic adaptability in varying slots without causing cross-link interference in fixed slots, thus resolving the contradiction between adaptability and interference.
Solution Approach 2:
The patent applies different TDD configuration qualities to different slot groups. Fixed slots have uniform, synchronized configuration across all cells (high quality for interference avoidance), while varying slots have cell-specific, dynamic configurations (high quality for adaptability). This local differentiation allows the system to simultaneously achieve both interference mitigation and dynamic adaptability.
2Object-affected harmful factors
If all cells use the same TDD configuration to avoid interference, then cross-link interference is reduced, but spectrum utilization and dynamic adaptation capability decrease
Solution Approach 1:
By dividing TDD slots into fixed and varying groups, the patent enables interference-free fixed slots to maintain stable communication while varying slots dynamically adjust to traffic demands. This segmentation allows the system to achieve high spectrum utilization through dynamic adaptation in varying slots without sacrificing interference protection in fixed slots.
Solution Approach 2:
The patent ensures continuous useful action by maintaining reliable communication in fixed slots while enabling continuous optimization of spectrum utilization through dynamic configuration changes in varying slots. This continuous adaptation in varying slots improves overall spectrum utilization without interrupting the stable communication provided by fixed slots.
3Adaptability or versatility
If unsynchronized networks operate on adjacent frequencies, then network independence is maintained, but interference control capability deteriorates
Solution Approach 1:
The patent creates equipotential conditions for interference control by synchronizing fixed slot configurations across all cells and operators. This synchronization ensures that during fixed slots, all cells are in the same state (either all transmitting or all receiving), eliminating cross-link interference. This equipotential approach allows unsynchronized networks to maintain independence while achieving coordinated interference control in fixed slots.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
There is presented a method for a network node for reducing interference in a wireless device (200), the wireless device operating using a time division0duplex, TDD, configuration in a cell, from at least another wireless device operating in a neighbouring cell using another TDD configuration. The TDD configuration is divided into different time units for at least downlink, DL, and uplink, UL, transmission. The method includes assigning time units in the TDD configuration to one of at least two time unit groups, where the assignment of a time unit to a time unit group is based the interference from the neighboring cell using the another TDD configuration. The method further includes using different link adaptions for the at least two time unit groups. The is also presented a network node.