Hand Over in 4G/LTE Networks

Department of Digital Systems Msc. Digital Communications and Networks

HANDOVER IN 4G NETWORKS Oikonomakis Oikonomakis Spyridon   Pantelopoulou Charikleia

STRUCTURE OF PRESENTATION  

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Handover asics Handover in and !etween "# networks Handover procedures $%%% &'(.)*m +dvanced handover features $%%% &'(.)*m ,egacy supported handover $%%% &'(.)*m Handover -ramework #PP ,/%0 +dvanced

THE TERM HANDOVER  /he process of transferring an ongoing call or data session from one channel to another in a cellular network. asic reasons why a handover might !e conducted2  /he user has moved out of range  /he !ase station is full 

$t is a key component in cellular network mo!ility management as it

HANDOVER FRAMEWORK REQUIREMENTS 

,atency and -le5i!ility

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Scala!ility of handover framework to handle increased handovers without compromising latency performance

Handling networks with heterogeneous S entities 6pico 7 femtocells8  Optimi9ations to allow handover to multicarrier0capa!le devices. 

IEEE 802.16M & 3GPP LTE  ADVANCED Physical layer frame of $%%% &'(.)*m designed with legacy of $%%% &'(.)*e allowing operation2 %ither on separate fre3uency assignments Or on the same fre3uency assignment with proper time0 division 9one partitioning !etween them 6,:one; M9one8 Providing legacy access service network 6+SN8 support mode 6plug0and0play8 

,/% < +dvanced designed with legacy of #SM7%D#%; #%=+N and >M/S handover and cell reselection to7from the legacy systems through treating them as inter0=+/ networks.

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HANDOVER IN UMTS AND WIMA!

E-UTRAN

IEEE – 802.16m

DEPLO"MENT SCENARIOS IEEE # 802.16M

a) greenfeld deployment (ne !pe"tr#m) $) m%&ed deployment' "arr%er re#!e ") m%&ed deployment' "arr%er oerlay 

IEEE # 802.16E & IEEE # 802.16M COE!ISTENCE ARCHITECTURE

OVERALL HANDOVER PROCEDURES

Preparation and $nitiation  %5ecution 

Completion  %5ception Handling 

ADVANCED HANDOVER FEATURES IEEE 802.16M #oal2 /o reduce latency during handover in physical and M+C layers and provide a !etter end0user e5perience 

+dvanced handover enhancements !ased on the general handover call ?ow2 Seamless Handover  % Handover 6%ntry efore reak8 

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Newly introduced in the $%%% &'(.)*m air interface protocol2 ,egacy Supported Handover  Multicarrier Handover 

E$$ HANDOVER PROCEDURES

eneral E** +andoer pro"ed#re!, a) !%ngle-

LEGAC" SUPPORTED HANDOVER IEEE 802.16M %1  /here are four possi!le scenarios for handover2 

Handover from a )*e S to )*m S2 )*e S to mi5ed0mode)*m S  )*e S to advanced only )*m S 

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Handover from a )*m S to )*e S 2 advanced only )*m S to )*e S  mi5ed0mode )*m S to legacy )*e S 

LEGAC" SUPPORTED HANDOVER IEEE 802.16M %2

andoer pro"ed#re rom an IEEE 802.16e */ to a m%&ed-mode IEEE 802.16m */

LEGAC" SUPPORTED HANDOVER IEEE 802.16M %3 

Handover from a )*e S to a )*m Only S 6direct handover8 Case of the largest interruption time due to lack of the demanded Ss@ interfaces  ,egacy +SN 2  Security update is a typical intra0)*m handover case  =e3uires capa!ility negotiation and M+C conte5t setup  )*m +SN2  =e3uires full network entry 

LEGAC" SUPPORTED HANDOVER IEEE 802.16M %4 

Handover from a )*m S to a )*e S %ither the )*m MS performs legacy handover to the )*e S through the ,9one  Or the )*m MS performs direct handover to the )*e S through the M:one 

THE HANDOVER FRAMEWORK OF 3GPP LTEADVANCED 

Hard handover is similar to $%%% &'(.)*m

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DiAerences2 +llows only % 6reak efore %ntry8 operation  Handover initiation and target selection are more tightly controlled !y the network  Supports seamless and lossless handover  >ser procedure can !e assigned in a per resource !earer 6=8 manner  Packet Data Convergence Protocol 6PDCP8 handles diAerently the data forwarding at the >% and eNode sides in diAerent modes 

INTERWORKING $ETWEEN IEEE 802.16M AND 3GPP LTE ADVANCED %1 Handover from $%%% &'(.)*m to #PP ,/%0+dvanced can use tow layer0( protocols2 $%%% &'(.)*m generic M+C layer0( transfer tunnel  $%%% &'(.() media0independent handover protocol 

#iven these frameworks and M+C layer control signaling there can !e support of2 

single0radio handover

INTERWORKING $ETWEEN IEEE 802.16M AND 3GPP LTE ADVANCED %2 Handover from #PP ,/%0+dvanced to $%%% &'(.)* family supports dual radio procedure via layer  transport.  /he #PP Service and +rchitecture ( 6S+(8 speci4cation re3uires layer  handover signaling for >% to preregister with BiM+ network.  Disadvantage2 No layer0( radio access network ( 6=+N(8 speci4cation de4ned to optimi9e handover 

CONCLUSIONS =educing service interruption time is !ecoming more in ne5t0generation wireless systems. $M/0+dvanced Systems provide advanced handover mechanisms in order to provide enhanced user e5perience during handover. $mportant re3uirement when design $%%% &'(.)*m and #PP systems is2 ,egacy supported mo!ility management +ll previously descri!ed advanced features of handover mechanisms enhance the user e5perience !y2

QUESTIONS''' THANK "OU FOR "OUR ATTENTION