MME MDT Configuration via PLMN List Storage

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

In mobile communication systems, when a User Equipment (UE) initially accesses a network without being subscribed to perform Minimization of Drive-Tests (MDT) measurements, changes in subscription information during a connected state allow MDT measurements, but current standards fail to correctly configure MDT measurements due to lack of necessary PLMN LIST information at the base station.

Innovation Solution

The Mobility Management Entity (MME) stores and updates the user consent and PLMN LIST information upon notification of subscription changes, ensuring accurate MDT measurement configuration by either refusing or sending a Trace Start message with the PLMN LIST to the base station, preventing wrong configuration operations and enabling failure reason identification.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If the base station configures MDT measurement without receiving PLMN LIST information from MME, then the MDT measurement can be activated, but the configuration is wrong and cannot be executed properly

Engineering Contradiction:

ImproveMDT measurement activation speedVSAvoidMDT configuration accuracy

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The MME stores the PLMN LIST information in advance when receiving subscription change notifications from HSS, before the MDT measurement activation request arrives. This preliminary storage ensures that when the Trace Start message is sent later, the PLMN LIST is already available, preventing configuration errors while maintaining fast activation.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The MME acts as an intermediary between HSS and the base station (eNB). It receives and stores PLMN LIST information from HSS, then forwards it to the eNB when activation is needed. This intermediary role ensures information completeness while maintaining system efficiency.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Reliability

If the MME stores PLMN LIST information upon subscription change notification, then the MDT configuration accuracy is improved, but the network signaling overhead increases

Engineering Contradiction:

ImproveMDT configuration accuracyVSAvoidnetwork signaling overhead

Core Design Contradiction:

ReliabilityVSQuantity of substance

Solution Approach 1:

The MME utilizes the existing subscription change notification signaling from HSS to obtain and store the PLMN LIST information. This approach reuses already-present signaling rather than introducing separate dedicated signaling, thus improving configuration accuracy without significantly increasing network overhead.

Inventive Principle:

Principle #10Preliminary action

3Reliability

If the MME sends Trace Start message with PLMN LIST to the base station, then the MDT measurement configuration is accurate, but the message complexity increases

Engineering Contradiction:

ImproveMDT configuration accuracyVSAvoidmessage structure complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The MME combines the PLMN LIST information with the existing Trace Start message structure used in 3GPP standards. By merging the additional information into the already-established signaling framework, the solution achieves accurate configuration while minimizing the increase in message complexity.

Inventive Principle:

Principle #5Merging (Combining)

Data Source

PatentEP2882206B1Method and device for performing MDT measurement configuration

Publication Date: 2016.12.14 CHINA ACAD OF TELECOMM TECH

Figure 1
Figure 2~3
Figure 4

AI summary

Disclosed are a method and device for performing MDT measurement configuration. The method includes: after receiving a notification of a change of subscription information about a user equipment, an MME storing a PLMN list for the user equipment to perform MDT measurement carried in the notification; and after receiving a notification for activating MDT measurement of the user equipment, the MME sending a trace start message to a serving base station of the user equipment, wherein the trace start message carries the PLMN list for the user equipment to perform MDT measurement.