Macro eNB Adaptive Transmission in Almost Blank Subframes

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

In wireless communication systems, the use of Almost Blank Subframes (ABS) in LTE networks reduces interference but also decreases throughput, as macro eNBs do not transmit data during designated ABS periods, limiting their operational efficiency.

Innovation Solution

The macro eNB selectively transmits data to a subset of macro UEs during ABS periods using reduced power levels or beamforming techniques, ensuring minimal interference with pico UEs while maintaining or enhancing network throughput.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If ABS periods are used to reduce interference, then interference with pico UEs is reduced, but throughput of macro eNB decreases

Engineering Contradiction:
Improveinterference with pico UEsVSAvoidthroughput of macro eNB
Core Design Contradiction:
Object-affected harmful factorsVSProductivity

Solution Approach 1:

The macro eNB applies different transmission strategies to different spatial regions: it uses reduced power or beamforming towards pico UE directions to minimize interference, while maintaining normal transmission power in other directions where pico UEs are not present. This spatially differentiated approach allows the macro eNB to protect pico UEs from interference while preserving throughput in directions where interference is not an issue.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The macro eNB dynamically adjusts its transmission parameters during ABS periods based on real-time channel conditions and pico UE locations. By adaptively selecting which macro UEs to serve and at what power levels, the system optimizes the balance between interfering with pico UEs and maintaining macro throughput, rather than applying a static restriction across all directions.

Inventive Principle:
Principle #15Dynamics

2Object-affected harmful factors

If macro eNB transmits at reduced power during ABS, then interference with pico UEs is reduced, but transmission capacity decreases

Engineering Contradiction:
Improveinterference with pico UEsVSAvoidtransmission capacity
Core Design Contradiction:
Object-affected harmful factorsVSPower

Solution Approach 1:

The macro eNB transmits at different power levels in different spatial directions: reduced power towards pico UE locations to minimize interference, and normal power in other directions to maintain transmission capacity. This directional power control allows the system to protect pico UEs while preserving overall macro transmission capacity.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The macro eNB segments its transmission capacity by selecting specific macro UEs to serve during ABS periods based on their spatial relationship with pico UEs. Macro UEs in directions away from pico UEs are prioritized for transmission, while those near pico UEs are deprioritized or excluded, effectively segmenting the transmission resources to minimize interference while maintaining capacity for non-interfering transmissions.

Inventive Principle:
Principle #1Segmentation

Data Source

PatentEP2590442B1Apparatus and method for adaptive transmission during almost blank subframes in a wireless communication network
Publication Date: 2018.08.01 BLACKBERRY LTD
  • EP2590442B1 patent drawingFigure 1
  • EP2590442B1 patent drawingFigure 2
  • EP2590442B1 patent drawingFigure 3A~3B

AI summary

A system and method for communication in a wireless communication network are disclosed. One embodiment of the system includes an overlay access node that supports Almost Blank Subframes (ABSs). The overlay access node, such as macro eNB, can receive measurement results from one or more user equipments, including macro user equipments (UEs) and/or pico (UEs), either directly or via an underlay access node, such as a pico eNB. The macro eNB can determine a set of macro UEs that are sufficiently close to the macro eNB for transmission during ABSs with a low transmission power or beamforming without significant interference to the pico UEs. This scheme improves the throughput of transmission between the macro eNB and macro UEs while reducing interference to the pico UEs.