Small Cell Discovery via Backhaul Quality Assessment

Solution Overview

Problem

In 5G communication systems, the discovery of small cells in heterogeneous networks is hindered by unreliable backhaul connections between small cells and the core network, leading to performance degradation and service interruptions, as existing methods rely solely on received signal strength without considering backhaul quality.

Innovation Solution

A method for small cell discovery that includes assessing a Wireless Backhaul Connection Indicator (WBCI) to ensure a suitable backhaul connection exists before handover, using either instantaneous or stochastic WBCI values determined by the macro base station or user equipment, to guarantee a reliable connection to the core network.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If inter-frequency scanning is performed to discover small cells, then small cell discovery capability is improved, but service interruption and energy consumption increase

Engineering Contradiction:

Improvesmall cell discovery capabilityVSAvoidservice continuity

Core Design Contradiction:

Adaptability or versatilityVSReliability

Solution Approach 1:

The macro base station performs preliminary actions by transmitting discovery reference signals and providing assistance information to UEs before the UEs need to perform inter-frequency scanning. This allows UEs to discover small cells more efficiently without extensive scanning, reducing service interruption while maintaining discovery capability

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The macro base station acts as an intermediary by transmitting discovery reference signals and assistance information to help UEs discover small cells. This intermediary approach enables UEs to obtain small cell information without performing extensive inter-frequency scanning, thereby reducing service interruption and energy consumption while maintaining discovery capability

Inventive Principle:

Principle #24Intermediary (Mediator)

2Measurement precision

If inter-frequency scanning is performed continuously, then small cell discovery accuracy is improved, but energy consumption increases

Engineering Contradiction:

Improvesmall cell detection accuracyVSAvoidUE energy consumption

Core Design Contradiction:

Measurement precisionVSUse of energy by moving object

Solution Approach 1:

The macro base station performs preliminary actions by transmitting discovery reference signals and providing assistance information to UEs before the UEs need to perform inter-frequency scanning. This allows UEs to discover small cells more efficiently without extensive scanning, reducing service interruption while maintaining discovery capability

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

Instead of requiring complete inter-frequency scanning, the system uses partial action by providing assistance information that contains key small cell parameters. This partial information approach enables UEs to make informed decisions without exhaustive scanning, significantly reducing energy consumption while maintaining adequate discovery accuracy

Inventive Principle:

Principle #16Partial or excessive action

3Speed

If handover to small cell is performed based on signal strength alone, then connection speed is improved, but reliability of backhaul connection deteriorates

Engineering Contradiction:

Improvehandover speedVSAvoidbackhaul connection reliability

Core Design Contradiction:

SpeedVSReliability

Solution Approach 1:

The macro base station performs preliminary actions by transmitting discovery reference signals and providing assistance information to UEs before the UEs need to perform inter-frequency scanning. This allows UEs to discover small cells more efficiently without extensive scanning, reducing service interruption while maintaining discovery capability

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system implements feedback mechanisms where the macro base station provides assistance information about small cell backhaul connection quality to UEs. UEs use this feedback information to make informed handover decisions, selecting small cells with reliable backhaul connections. This feedback approach maintains handover speed while improving reliability by preventing handovers to small cells with poor backhaul connections

Inventive Principle:

Principle #23Feedback

Data Source

PatentUS10701621B2Small cell discovery in a communication network

Publication Date: 2020.06.30 SAMSUNG ELECTRONICS CO LTD

AI summary

The present disclosure relates to a pre-5th-Generation (5G) or 5G communication system to be provided for supporting higher data rates Beyond 4th-Generation (4G) communication system such as Long Term Evolution (LTE). A method for operating a terminal in a wireless communication system includes transmitting, to a macro base station, first information for indicating a link quality between the terminal and a small base station. The method also includes receiving, from the macro base station, a message for instructing a handover, and performing the handover from the macro base station to the small base station according to the message. The handover is determined based on the first information and second information for indicating another link quality between the small base station and the macro base station.