UL-DL Configuration Negotiation for Interference Mitigation in Small Cells

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

In cellular wireless networks, downlink interference significantly impacts uplink Signal-to-Interference-Noise-Ratio (SINR) of user equipment, particularly between stations with different uplink-downlink configurations, leading to severe interference issues.

Innovation Solution

A method where stations negotiate with neighboring stations to determine suitable uplink-downlink configurations based on collective traffic conditions, using criteria such as pathloss and fading to mitigate interference, either through dynamic or static negotiation, and adjusting transmission power to reduce interference.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If stations randomly choose transmission directions and different UL-DL configurations, then traffic adaptation is improved, but downlink interference to uplink transmissions increases significantly

Engineering Contradiction:
Improvetraffic adaptationVSAvoiddownlink interference
Core Design Contradiction:
Adaptability or versatilityVSObject-affected harmful factors

Solution Approach 1:

The patent implements dynamic UL-DL configuration negotiation between neighboring stations based on real-time traffic conditions. Stations transition from static, random configuration selection to dynamic adjustment where configurations are negotiated and coordinated to avoid interference, while still adapting to changing traffic demands. This resolves the contradiction by making the system dynamically adjustable rather than fixed or purely random.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent establishes a feedback mechanism where stations monitor their traffic conditions and interference levels, then negotiate configuration adjustments with neighboring stations. The negotiation process uses feedback about current UL-DL traffic demands and interference impact to select optimal configurations. This feedback loop enables traffic adaptation while preventing severe interference through coordinated configuration selection.

Inventive Principle:
Principle #23Feedback

2Adaptability or versatility

If stations use different UL-DL configurations to meet diverse traffic conditions, then service flexibility is improved, but uplink SINR performance deteriorates due to severe downlink interference

Engineering Contradiction:
Improveservice flexibilityVSAvoiduplink SINR
Core Design Contradiction:
Adaptability or versatilityVSReliability

Solution Approach 1:

The patent introduces a negotiation mechanism as an intermediary process between neighboring stations. This negotiation acts as a mediator that coordinates UL-DL configuration selection, ensuring that stations with potentially conflicting configurations (one in downlink, another in uplink) do not operate simultaneously. The intermediary negotiation process maintains service flexibility for individual stations while protecting uplink SINR through coordinated configuration selection.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent applies preliminary anti-action by having stations negotiate and pre-coordinate their UL-DL configurations before transmission occurs. Stations proactively identify and resolve potential interference conflicts by selecting compatible configurations in advance, rather than reacting to interference after it occurs. This preliminary coordination maintains service flexibility while preventing uplink SINR degradation.

Inventive Principle:
Principle #9Preliminary anti-action

3Extent of automation

If stations independently select UL-DL configurations based on local traffic conditions, then autonomous adaptation is improved, but network-wide interference coordination deteriorates

Engineering Contradiction:
Improveautonomous adaptationVSAvoidnetwork interference
Core Design Contradiction:
Extent of automationVSObject-generated harmful factors

Solution Approach 1:

The patent merges autonomous local decision-making with network-wide coordination by combining independent traffic condition monitoring with collaborative negotiation. Each station independently assesses its own traffic needs (autonomous adaptation) but combines this with negotiation outcomes from neighboring stations (network-wide coordination). This merging of independent and collaborative processes enables both autonomous adaptation and effective interference coordination across the network.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The patent creates a universal negotiation framework that serves multiple functions: it enables autonomous traffic adaptation, coordinates interference avoidance, and maintains network-wide synchronization. The negotiation mechanism is a multi-functional process that simultaneously achieves local autonomy and global coordination, resolving the contradiction between independent adaptation and network-wide interference management.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Data Source

PatentEP2663147B1Interference mitigation method in cellular wireless network, and apparatus with the same
Publication Date: 2019.01.16 IND TECH RES INST
  • EP2663147B1 patent drawingFigure 1A
  • EP2663147B1 patent drawingFigure 1B
  • EP2663147B1 patent drawingFigure 2A

AI summary

Interference mitigation methods in a small cell wireless network are provided. In the methods, negotiations between different stations are provided for interference mitigation. By such negotiations, UL-DL configurations are chosen in considering interference between neighboring stations and the interferences therefrom are effectively mitigated.