Mobile Station Interference Mitigation via Base Station Coordination

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current technologies face challenges in mitigating mobile station-to-mobile station (MS-to-MS) interference in wireless networks, particularly when FDD and TDD systems operate in proximity, due to cost, size, and frequency spectrum constraints, with existing solutions like filters and guard bands being inefficient or costly, and lacking dynamic adaptation.

Innovation Solution

A time-sharing technique using a common unlicensed channel for inter-system communication, where mobile stations detect interference using alternate technologies like Bluetooth or Wi-Fi, identify the interferer, and communicate this information to their base stations to adjust transmission patterns and reduce interference through dynamic channel changes.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If filters are used in both transmit and receive chains of mobile devices to mitigate MS-to-MS interference, then interference reduction is achieved, but cost, size, and weight of mobile devices increase

Engineering Contradiction:
ImproveMS-to-MS interferenceVSAvoidmobile device complexity
Core Design Contradiction:
Object-affected harmful factorsVSDevice complexity

Solution Approach 1:

The patent introduces base stations as intermediaries to manage interference between mobile stations. Instead of equipping each mobile device with complex filters, the base station receives interference reports from mobile stations and coordinates transmission timing and frequency to prevent interference, thereby reducing MS-to-MS interference without increasing mobile device complexity

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent implements a feedback mechanism where mobile stations report interference conditions to base stations, which then adjust transmission parameters. This closed-loop system enables dynamic interference mitigation through coordinated control between base stations and mobile stations, avoiding the need for complex local filtering in mobile devices

Inventive Principle:
Principle #23Feedback

2Object-affected harmful factors

If a guard band or frequency gap is used between FDD and TDD systems to reduce interference, then interference mitigation is achieved, but valuable frequency spectrum is wasted

Engineering Contradiction:
ImproveMS-to-MS interferenceVSAvoidfrequency spectrum usage
Core Design Contradiction:
Object-affected harmful factorsVSQuantity of substance

Solution Approach 1:

The patent replaces static guard bands with dynamic transmission coordination. Base stations dynamically adjust transmission timing and frequency based on real-time interference conditions reported by mobile stations, allowing efficient spectrum utilization while maintaining interference protection without requiring fixed frequency gaps

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent changes the approach from fixed frequency separation to dynamic parameter adjustment. Base stations modify transmission parameters such as timing advance and frequency selection based on actual interference conditions, enabling flexible spectrum sharing that eliminates the need for large static guard bands while maintaining interference mitigation

Inventive Principle:
Principle #35Parameter changes

3Object-affected harmful factors

If time synchronization is used to reduce interference between TDD systems, then interference scenarios are reduced, but system complexity and coordination requirements increase

Engineering Contradiction:
ImproveMS-to-MS interferenceVSAvoidsystem coordination complexity
Core Design Contradiction:
Object-affected harmful factorsVSDevice complexity

Solution Approach 1:

The patent uses interference reports from mobile stations as feedback to base stations, which then adjust transmission timing dynamically. This feedback-based timing coordination achieves interference reduction without requiring complex centralized synchronization, as each base station independently optimizes timing based on local interference conditions

Inventive Principle:
Principle #23Feedback

Data Source

PatentEP2250852B1System and method for minimizing inter-communications system mobile station-to-mobile station interference
Publication Date: 2013.02.13 MOTOROLA SOLUTIONS INC
  • EP2250852B1 patent drawingFigure 1A~1C
  • EP2250852B1 patent drawingFigure 2
  • EP2250852B1 patent drawingFigure 3

AI summary

A system and method for minimizing inter-communications system mobile-to-mobile station interference includes a plurality of base stations (BS A and BS B) and a plurality of mobile stations (MS A and MS B) each communicating with a base station using a first mode of communication. A first mobile station (MS A) sends a message using a second mode of communication upon detecting interference with another mobile station (MS B) to determine the source of the interference. Once determined, the first mobile station (MS A) communicates with its base station (BS A) which, in turn, communicates with the second mobile station's base station (BS B) using a backhaul network. The second mobile station's base station (BS B) may then instruct the second mobile station (MS B) to alter its transmission characteristics based upon instructions from the second base station (BS B) in order to reduce interference and improve overall communications quality.