Device to device communication

New Handoff Management for D2D Communication inLong Term Evolution-Advanced Cellular Network

Mohammad Dabibi

University of Tehran

[email protected]

December 12, 2014

Mohammad Dabibi (University Of Tehran) D2D Handover December 12, 2014 1 / 34

Headline

1 Introduction to Device To Device CommunicationProximity Discovery and AwarnessClassification of D2D CommunicationCurrent Progress in Standardization

2 LTE-A Access, Core and Procotol Architecture for D2DD2D Function Block in LTE-A SAE ArchitectureProtocol Stock and Bearer ManagementCommunication SenariosD2D Connection Request/Setup

3 Handover ThechnologyTarget Cell SelectionX2 Backhauling and Handover Using X2Proposed LTE handover using D2D


What is D2D?

Direct Communication Between Nearby Mobiles.


How To Get Proximity Awareness?


Discovery And Broadcast


User Experience


User Experience Cont’n










Classifiation of D2D Communication

• Licensed Band: Better interference avoidance under a controlledenvironment. Ex. Femtocells / Picocells Under LTE-Alicensed band


Current Progress in D2D Communication

• June 2011: Study item description on the radio aspect of D2Ddescovery and Communication by Qualcomm

• Augest 2011: Direct over-the-air LTE D2D discovery andCommunication

• June 2012: Identified potential requirements between proximate devicesas new step on Rel-12

• December 2012: Study on LTE Proximity Service in radio AccessNetwork ( D2D Discovery - D2D Communication )

• Current Work On: Discovery Signal design, Resource Allocation andScheduling, Synchronization mechanism.


D2D Function Block in LTE-A SAE Architecture

• ProSe: Proximity Discovery - Direct Communication• D2D Sessions: D2D session Could be initiated by sending an initiation

request to the Proximity Server in MME.• Radio Bearer Setup (Ud): MME is responsible for initiating Ud

interface.


D2D Function Block in LTE-A SAE Architecture Cont’n

• Radio Bearer Setup (Ud): MME is responsible for initiating Udinterface + Delivery IP address for D2D terminal devices.


Protocol Stock and Bearer Management

• Data Protocol Stock for D2D: D2D bearer has been set up betweenpeer devices.


D2D Design Aspect

• Modulation Format: LTE use SC-FDMA for UL and OFDMA in DL. IfSC-FDMA is used, the D2D UE needs to be equipped with anew SC-FDMA receiver.

• Frame Structure: Camping D2D on UL resources


D2D Design Aspect Cont’n

• Channel Measurements: Based on measurement reports


LTE-A Access, Core and Protocol Architecture for D2D

• D2D Communication Scenarios Direct Communication


D2D Ennhanced LTE Architecture

• New Interfaces PC1, PC2, PC3, PC4, PC5, PC6 and SGi


Security Architecture for D2D

• Main Security Feature:


D2D Connection Request


Handover Technologies

• Hard Handover break-before-make• Soft Handover make-before-break• handover procedure: measurements control, the measurements report,

handover decision, handover execution


Handover Process ( handover Decision )

Handover process may betriggered by:

1 Quality, filed strength ofDistance Values fallbellow/exceed theirthreshold

2 Periodic Check : PowerBudget HO, Umbrella HO


Handover Priority

• Handover Priority

1 Uplink and downlink Interference

2 Uplink Quality

3 Downlink Quality

4 Uplink Level

5 Downlink Level

6 Distance

7 Rapid Field Drop

8 Slow moving UE

9 Better Cell, i.e Periodic Check ( power Budget HO or Umbrella HO


Target Cell Selection


Handover in LTE-A

• Hard Handover High handover outage probability, Large Delay.

• Aspect on D2D To Provide Steamless access to Voice and Multimediaservice with Strict delay in D2D

• Solution 1. Semi-Soft-Handover 2. Handover Using D2DCommunication


Backhauling X2

• X2 The LTE Radio Access Network moves RNC functionality rothe eNodeB and introduced a new X2


LTE X2 Handover High Level Flow


LTE X2 Handover High Level Flow Cont’n


Proposed LTE D2D Handover

• Proposed: Handover During D2D Communication via Ud


Proposed LTE D2D Handover High Level Flow


References

T. S. Rappaport

Wireless communications, Prentice Hall, 1996

C. Lin, K. Sandrasegaran and S. Reeves

Handover Algorithm with Joint Processing in LTE-Advanced 2012 IEEE

J. Chang, Y. Li, Sh. Feng, H. Wang, C. Sun, Ph. Zhang

A Fractional Soft Handover Scheme for 3GPP LTE-Advanced System, IEEEInternational Conference, 2009.

M. Anas, F. D.Calabrese, P. E. Mogensen, C. Rosa, K. I. Pedersen

Performance Evaluation of Received Signal Strength Based Hard Handover forUTRAN LTE, IEEE Vehicular Technology Conference, 2007, pp.1046-1050.

K. Doppler, M. Rinne, C. Wijting, C. Ribeiro, and K. Hugl

Deviceto-device communication as an underlay to lte-advanced networks,Communications Magazine, IEEE, vol. 47, no. 12, pp. 4249, 2009.


The End


Device to device communication

Mobile

d2d bearer

d2d terminal devices

x2proposed lte handover

standardization2 lte

lte proximity service

discovery signal design

34d2d function block

proximity server