4.LTE Overview 69

8/18/2019 4.LTE Overview 69

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LTE Overview

Course Objectives:

·Understand the development of mobile communications, and Long

Term Evolution (LTE position and net!or" architecture#

·Understand the protocol architecture and basic technologies of E$

UT%&'#

·Understand "e LTE technologies#


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Contents

1 Overview........................................................................................................................................................1

)#) *ac"ground##########################################################################################################################################)

)#)#) +obile Communications Evolution###########################################################################################)

)#)# Comparison &mong -C.+&, T.$/C.+&, and C.+&000##############################################

)#)#1 -C.+& Evolution##################################################################################################################

)#)#2 T.$/C.+& Evolution#############################################################################################################1

)#)#3 C.+&00 Evolution################################################################################################################2

)# LTE Overvie! and /tandards .evelopment########################################################################################3

2 LTE Indexes and Requirements...................................................................................................................5

#) 4re5uenc *and .ivision#####################################################################################################################6

# 7ea" .ata %ate#####################################################################################################################################8

#1 Control 7lane .ela#############################################################################################################################8

#2 User 7lane .ela##################################################################################################################################8

#3 User Throughput###################################################################################################################################9

#6 /pectrum Efficienc#############################################################################################################################9

#8 +obilit################################################################################################################################################9

#9 Coverage##############################################################################################################################################

# /pectrum 4le;ibilit#############################################################################################################################

#)0 Coe;istence and and O7E>##########################################################################################################)0

3 LTE Architecture.........................................................................................................................................11

1#) /stem &rchitecture############################################################################################################################))

1# %adio 7rotocol &rchitecture###############################################################################################################)3


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1##) Control 7lane 7rotocol &rchitecture#######################################################################################)3

1## User 7lane 7rotocol &rchitecture############################################################################################)6

1#1 /)


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3#1# 7.U /tructure#########################################################################################################################1

" RR#..............................................................................................................................................................3$

6#) %%C 4unctions###################################################################################################################################1

6# %%C /tate##########################################################################################################################################20

6#1 '&/ /tate and the %elationship -ith the %%C state#########################################################################2)

6#2 %%C 7rocedure##################################################################################################################################2

6#2#) /stem


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LTE Overvie!

.evelopment and evolution of !ireless communication technologies

1.1.2 Comparison mong !C"M# T"$%C"M# and C"M2&&&

Comparison among -C.+&, T.$/C.+&, and C.+&000

/tandard -C.+& C.+&000 T.$/C.+&


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Chapter 8 Core LTE Technologies

-C.+& technolog roadmap

1.1.( T"$%C"M Evolution

DTE !ireless net!or" e5uipment supports smooth evolution of recent T. evolution

soft!are#

T. evolution can be divided into t!o stages: standard stage of C.+& technologies and

that of O4.+& technologies#

The standard stage of C.+& technologies can smoothl evolve to @/7& !ith

spectrum efficienc close to that of LTE#

3


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LTE Overvie!

Basic version

Short-term evolution version

Mid-term evolution version

Long-term evolution version (4G)

Phase I Phase II Phase III

C"M standard O)"M standard

'*++ ,-(/oice0"ata

re3uenc4 point

'*++ ,-506078%+08%+9

MBM%0Multi$Carrier

'*++ LTEO)"MM:MO

:MT$dv

T.$/C.+& evolution

1.1.5 C"M2&& Evolution

C.+& One is a collection of all


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1.2 LTE Overview and %tandards "evelopment

1=77 !or"ing groups started LTE standardi?ation in .ecember 002# LTE focuses on

the enhancement of UT%&' and UT%

The establishment of 1=77 standards can be divided into four stages including

re5uirements proposal, architecture establishment, detailed specifications, and testing

and verification#

1=77 !or"s in !or"group mode and %&')BB1B2B3 !or"groups are directl related to

LTE#

5


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LTE Overvie!

Organi?ation and establishment stages of 1=77 standards

6


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2 LTE :nde;es and -e3uirements

Knowledge points

/pectrum division

LTE sstem re5uirements

Others

7hsical channels and mapping relationship

4igure 6 sho!s the LTE inde;es and re5uirements prescribed b 1=77#

LTE inde;es and re5uirements

5


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2.1 )re3uenc4 Band "ivision

Table lists the E$UT%& fre5uenc bands#

E$UT%& fre5uenc bands

E$UT%&

Operating

*and

Uplin" (UL operating band */ receive

UE transmit

.o!nlin" (.L operating band */

transmit UE receive

.uple;

+ode

4ULFlo! G 4ULFhigh 4.LFlo! G 4.LFhigh

) )0 +@? G )90 +@? ))0 +@? G )80 +@? 4..

)930 +@? G ))0 +@? )10 +@? G )0 +@? 4..

1 )8)0 +@? G )893 +@? )903 +@? G )990 +@? 4..

2 )8)0 +@? G )833 +@? ))0 +@? G )33 +@? 4..

3 92 +@? G 92 +@? 96 +@? G 92+@? 4..

6 910 +@? G 920 +@? 983 +@? G 993 +@? 4..

8 300 +@? G 380 +@? 60 +@? G 60 +@? 4..

9 990 +@? G )3 +@? 3 +@? G 60 +@? 4..

)82# +@? G )892# +@? )922# +@? G )98# +@? 4..

)0 )8)0 +@? G )880 +@? ))0 +@? G )80 +@? 4..

)) )28# +@? G )23# +@? )283# +@? G )300# +@? 4..

) 69 +@? G 8)6 +@? 89 +@? G 826 +@? 4..)1 888 +@? G 898 +@? 826 +@? G 836 +@? 4..

)2 899 +@? G 89 +@? 839 +@? G 869 +@? 4..

H

)8 802 +@? G 8)6 +@? 812 +@? G 826 +@? 4..

###

11 )00 +@? G )0 +@? )00 +@? G )0 +@? T..

12 0)0 +@? G 03 +@? 0)0 +@? G 03 +@? T..

13 )930 +@? G ))0 +@? )930 +@? G ))0 +@? T..

16 )10 +@? G )0 +@? )10 +@? G )0 +@? T..

18 ))0 +@? G )10 +@? ))0 +@? G )10 +@? T..

19 380 +@? G 60 +@? 380 +@? G 60 +@? T..

1 )990 +@? G )0 +@? )990 +@? G )0 +@? T..

20 100 +@? G 200 +@? 100 +@? G 200 +@? T..

2.2 +eak "ata -ate

The instantaneous do!nlin" pea" rate reaches )00 +bitBs (3 bitBsB@? at 0 +@?

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do!nlin" spectrum band (t!o transmit antennas on the net!or" side and t!o receive

antennas on the UE side#

The instantaneous uplin" pea" rate reaches 30 +bitBs (#3 bitBsB@? at 0 +@? uplin"

spectrum band (one receive antenna on the UE side#

-idebands, + interval#

&dditionall, if the control plane operates at 3 +@? spectrum band, each cell is e;pectedto support 00 activated users#


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LTE Overvie!

)# The user throughput per +@? at the 3J Cumulative .istribution 4unction (C.4

must reach t!o to three times the throughput of %6 @/.7

# The average user throughput per +@? must reach three to four times the

throughput of %6 @/.7

%6 @/.7& uses one transmitter one receiver ()T)% !hile LTE uses t!o transmitterBt!o

receiver (T%#

Uplin":

)# The user throughput per +@? at the 3J C.4 must reach t!o to three times the

throughput of %6 @/U7

# The user throughput per +@? must reach t!o to three times the throughput of %6

@/U7

%6 @/U7& uses )T%, and so does LTE#

2.6 %pectrum Eicienc4

.o!nlin": On a net!or" !ith effective load, the target LTE spectrum efficienc(measured b the bit 5uantit per site, per @?, and per second is three to four times

more efficient than %6 @/U7 %6 @/.7& uses )T)% !hile LTE uses T%#

Uplin": On a net!or" !ith effective load, the target LTE spectrum efficienc (measured

b the bit 5uantit per site, per @?, and per second is t!o to three times more efficient

than %6 @/U7 %6 @/U7& uses )T%, and so does LTE#

2.7 Mobilit4

E$UT%&' can provide optimum net!or" performance for mobile users at the speed of

0–)3 "mBh, high performance services at the speed of )3–)0 "mBh, and cell net!or"

services at the speed of )0–130 "mBh (the speed even reaches 300 "mBh at specified

bands#

oice services and other realtime services provided in the %6 C/ domain are supported

b 7/ domain on the E$UT%&' and all these services can reach or e;ceed the 5ualit of

UT%&' services# The interrupt time caused b handovers !ithin the E$UT%& sstem

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must be shorter than or e5ual to the handover time of the =E%&' C/ domain#

Coverage

The E$UT%& sstem must fle;ibl support all coverage scenarios on the basis of reusing

the current UT%&' sites and fre5uencies to meet the preceding performance inde;es

such as the user throughput, spectrum efficienc, and mobilit#

The performance re5uirements of the E$UT%& sstem !ithin different coverage scope

are listed as follo!s:

)# Coverage radius !ithin 3 "m: The preceding performance inde;es such as the user

throughput, spectrum efficienc, and mobilit must be full satisfied#

# Coverage radius !ithin 10 "m: The throughput and spectrum efficienc areallo!ed to slightl drop but !ithin an acceptable range, and the mobilit inde;

must be full satisfied#

1# +a;imum coverage radius: )00 "m#

2.? %pectrum )le;ibilit4

On the one hand, the spectrum fle;ibilit allo!s deploment of E$UT%& at varied bands

including )#2 +@?, 1 +@?, 3 +@?, )0 +@?, )3 +@?, and 0 +@?# The E$UT%&

supports paired and unpaired spectrums#

On the other hand, the spectrum fle;ibilit allo!s consolidation of spectrum bands#

2.1& Coe;istence and :nteroperabilit4 wit= E;isting '*++ %4stems


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LTE Overvie!

)# E$UT%&' and UT%&'B=E%&' multi$mode terminals support

UT%&'B=E%&' measurement and handover bet!een E$UT%&' sstems and

UT%&'B=E%&' sstems#

# The E$UT%&' sstem supports inter$sstem measurement#

1# The handover interrupt time bet!een %$UT%&' and UT%&' must be shorter

than 100 ms for realtime services#

2# The handover interrupt time bet!een E$UT%&' and UT%&' must be shorter

than 300 ms for non$realtime services#

3# The handover interrupt time bet!een E$UT%&' and =E%&' must be shorter

than 100 ms for realtime services#

6# The handover interrupt time bet!een E$UT%&' and =E%&' must be shorter

than 300 ms for non$realtime services#

8# 7aging information of onl one of the =E%&', UT%&, or E$UT%& sstems

needs to be monitored for multi$mode terminals in non$active state (similar to %6


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' LTE rc=itecture

Knowledge points

%adio protocol structure

/) interface

> interface

'.1 %4stem rc=itecture

LTE adopts an O4.+$based air interface technolog !hich is different from those of

= and 1=# LTE adopts a flat net!or" architecture !ithin !hich E$UT%&' contains

onl e'ode*s instead of %'C, so as to optimi?e the traditional 1= net!or" architecture#

LTE supports functions of 7.C7B%LCB+&CBphsical laer protocols on the E$UT%&

user plane and functions of the %%C protocol on the control plane# 4igure 9 sho!s the E$

UT%&' sstem architecture#

E$UT%&' architecture


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e'ode*s are connected over an ; interface and ever e'ode* is connected to the

Evolved 7ac"et Core (E7C net!or" over an /) interface# The user plane of /)

interfaces terminates on the /erving$=ate!a (/$=- and the control plane of /)

interfaces terminates on the +obile +anagement Entit (++E# The other end of the

control plane and user plane terminates on the e'ode*# 4unctions of all 'Es in the

preceding figure are listed as follo!s:

e'ode*

*esides the original e'ode* functions, e'ode* of LTE underta"es most of original

%'C functions such as phsical laer, +&C (including @&%A, %LC laer (including

&%A functions, 7.C7, %%C, scheduling, radio access control, access mobilit

management, and radio resource management among different cells#

LTE e'ode*s have the follo!ing functions:

− +anage radio resources: %adio bearer control, radio access control, connection

mobilit control, and dnamic resource assignment of uplin" and do!nlin"

(scheduling#

− Compress


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The function of the ++E is separated from that of the gate!a# The control planeBuser

plane separated structure facilitates net!or" deploment, single technolog evolution,

and fle;ible capacit e;pansion#

− '&/ signaling

− '&/ signaling securit

− &/ securit control

− +obile signaling among 1=77 radio net!or"s

− The reachabilit of an UE in the idle state (including the control and

implementation of paging signal re$transmission

− Trac"ing area list management

− 7$=- or /$=- selection

− ++E selection at the time of handover

− /=/' selection at handover to = or 1=77 net!or"

− %oaming

− &uthentication

− *earer management, including dedicated bearer establishment

− ET-/ signal transmission

/$=-

&s the anchor point at local e'ode* handover, /$=- implements the follo!ing

functions: data transfer bet!een the e'ode* and the public data gate!a, do!nlin"

pac"et buffer, and user$based billing#

− Local mobile anchor points at e'ode* handover

− +obile anchor points among 1=77 sstems#

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LTE Overvie!

− .o!nlin" pac"et buffering and initiali?ation of net!or"$triggered service re5uest

procedure in the E$UT%&' idle mode

− La!ful interception

− 7ac"et routing and for!arding

− Transport$laer pac"et mar"ing (uplin"Bdo!nlin"

− &ccounting on user and AC< granularit for inter$operator charging#

− Uplin"Bdo!nlin" charging per UE, 7.', or AC<

7.' gate!a (7$=-

&s the designated anchor point of the data bearer, the 7ublic .ata 'et!or" =ate!a (7$

=- has the follo!ing functions: 7ac"et for!arding, pac"et resolving, la!ful

interception, service$based billing, Ao/ control, and interconnection !ith non$1=77

net!or"s#

− 7er$user pac"et filtering (for e;ample, utili?e deep pac"et inspection

− La!ful interception

− interface in the ne! LTE

architecture#

4igure 9 sho!s the functional split bet!een E$UT%&' and E7C# ello! bo;es depict

the logical nodes, !hite bo;es the functional entities of the control plane, and blue bo;es

the radio protocol laers#

4


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4unctional split bet!een E$UT%&' and E7C

'.2 -adio +rotocol rc=itecture

'.2.1 Control +lane +rotocol rc=itecture

4igure )0 sho!s the control plane protocol architecture#

Control plane protocol stac"

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LTE Overvie!

The 7.C7 terminates at e'ode* and implements functions such as control plane

encrption and integrit protection#

The %LC and +&C terminate at e'ode* on the net!or" side and implement identical

functions of the user plane and control plane#

The %%C terminates at e'ode* and implements such functions as broadcast, paging,

%%C connection management, %* control, mobilit, and UE measurement reporting and

control#

The '&/ terminates at ++E and implements such functions as E7/ bearer

management, authentication, idle$mode E7/ Connection +anagement (EC+, idle$mode

EC+ paging, and securit control#

'.2.2


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'.'.1 %1 :nterace

The /) interface is defined as the interface bet!een the E$UT%&' and E7C# The /)interface contains t!o parts: the control plane /)$++E interface and user plane /)$U

interface# The /)$++E interface is defined as the interface bet!een the e'ode* and

++EM the /)$UE interface is defined as the interface bet!een the e'ode* and /$=-#

4igure ) and 4igure )1 respectivel sho! the protocol stac" architecture of the /)$

++E interface and /)$U interface#

/) interface control plane (e'ode*$++E

/) interface user plane (e'ode*–/$=-

7


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LTE Overvie!

The /) interface has the follo!ing ac"no!ledged functions:

E$%&* service management

− Establishment, modification, and release

UE mobilit in the EC+$CO''ECTE. state

− @andover !ithin the LTE sstem

− @andover bet!een the LTE sstem and the 1=77 sstem

/) paging

'&/ signaling transmission

/) interface management

− Error indication

− %eset

'et!or" sharing

%oaming and area restriction

'&/ node selection


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%&' information management

The /) interface has the follo!ing ac"no!ledged signaling procedures:

E$%&* signaling procedure

− E$%&* establishment

− E$%&* modification

− ++E$initiated E$%&* release

− e'ode*$initiated E$%&* release

@andover signaling procedure

− @andover preparation

− %esource assignment

− @andover termination

− @andover cancellation

7aging

'&/ transmission procedure

− .irect uplin" transmission (initial UE message

− .irect uplin" transmission (uplin" '&/ transmission

− .irect do!nlin" transmission (do!nlin" '&/ transmission

Error indication procedure

− e'ode*$initiated error indication

− ++E$initiated error indication

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LTE Overvie!

%eset

− e'ode*$initiated reset

− ++E$initiated reset


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$

U adopt the same user plane protocol to reduce protocol processing at e'ode* data

for!ard#

'.'.2 @2 :nterace

The > interface is defined as the interface bet!een e'ode*s# The > interface contains

t!o parts: the >$C7 and >$U, !here the >$C7 is the control plane interface bet!een

e'ode*s and the >$U is the user plane interface bet!een e'ode*s# 4igure )3 and

4igure )6 respectivel sho! the protocol stac" architecture of the >$C7 interface and

>$U interface#


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LTE Overvie!

> interface control plane

> interface user plane

The >$C7 has the follo!ing functions:

UE mobilit in the EC+$CO''ECTE. state !ithin the LTE sstem

− Conte;t transfer from the source e'ode* to the target e'ode*

− User plane channel control bet!een the source e'ode* and the target e'ode*

− @andover cancellation


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Uplin" load management

=eneral > interface management and error processing

− Error indication

The >$C7 interface has the follo!ing ac"no!ledged signaling procedures:

@andover preparation

@andover cancellation

UE conte;t release

Error indication

Load management

The management of load among cells is implemented over the > interface#

4igure )8 sho!s that the LO&. interface LO&.


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( +=4sical La4er

(.1 )rame %tructure

The LTE sstem supports the follo!ing t!o radio frame structures:

/tructure ): &pplicable to the 4.. mode#

/tructure : &pplicable to the T.. mode#

4igure )9 sho!s the frame structure )# Ever )0 ms radio frame is divided into ten sub$

frames of fi;ed length# Each sub$frame contains t!o time slots each of !hich is 0#3 ms

long#

4rame structure )

4or 4.., at ever )0 ms, ten sub$frames can be used for do!nlin" transmission and

another ten sub$frames can be used for uplin" transmission# The uplin" transmission and

do!nlin" transmission are separated on the fre5uenc domain#

(.2 +=4sical -esources

The minimum resource unit for uplin"Bdo!nlin" transmission in the LTE sstem is called

the %esource Element (%E#

&t the time of data transmission, the LTE sstem consolidates uplin" and do!nlin" time$

fre5uenc domain phsical resources into %esource *loc"s (%*s for scheduling and

allocation#


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/everal %Es constitute an %*# There are ) consecutive sub$carriers on the fre5uenc

domain and seven consecutive O4.+ smbols (si; mar"s !ith the E;tended C7# That

is, the fre5uenc domain !idth is )90 "@? and the time length is 0#3 ms#

4igure ) and 4igure 0 respectivel sho! the phsical resource structures of do!nlin"

and uplin" slots#

7hsical resource structure of do!nlin" slot


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7hsical resource structure of uplin" slot

(.' +=4sical C=annels

The do!nlin" phsical channels contain the follo!ing channels:

1 7hsical *roadcast Channel (7*C@

− The coded *C@ transmission bloc" maps to four sub$frames !ithin an 20 ms

interval#

− The 20 ms timing is obtained b blind tests, namel, no specified signaling

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LTE Overvie!

indicates the 20 ms timing#

− -ith e;cellent$enough channels, ever sub$frame that the 7*C@ located canseparatel decode signals#

2 7hsical Control 4ormat


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# 7hsical Uplin" /haring Channel (7U/C@

− Carr the UL$/C@ information#

$ 7hsical %andom &ccess Channel (7%&C@

− Carr the random access preamble#

(.( Transport C=annels

The do!nlin" transport channels contain the follo!ing channels:

1% *roadcast Channel (*C@

− 4i;ed predefined transport format

− *roadcast in the entire coverage area of the cell

11 .o!nlin" /haring Channel (.L$/C@

− /upport @&%A#

− period to the

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LTE Overvie!

UE#


− +ap to phsical resources !hich can be used dnamicall also for traffic or other

control channels#

13 +ulticast Channel (+C@


− /upport +ulticastB*roadcast over /ingle 4re5uenc 'et!or" (+*/4' combingof +*+/ transmission on multiple cells#

− /upport semi$static resource allocation#

The uplin" transport channels contain the follo!ing channels:

14 Uplin" /haring Channel (UL$/C@

−

/upport beamforming#

−


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(.5 Mapping Between Transport C=annels and +=4sical C=annels

4igure ) and 4igure respectivel sho! the mapping relationships bet!een

do!nlin"Buplin" transport channels and do!nlin"Buplin" phsical channels#

+apping bet!een do!nlin" transport channels and do!nlin" phsical channels

+apping bet!een uplin" transport channels and uplin" phsical channels

(.6 +=4sical %ignals

7hsical signals correspond to several phsical laer %Es, but do not carr an

information that comes from higher laers#

The do!nlin" phsical signals include the reference signal and the snchroni?ation

signal#

%eference signal

The do!nlin" reference signals include the follo!ing three tpes of reference signals:

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LTE Overvie!

− Cell$specific reference signals, associated !ith non$+*/4' transmission

− +*/4' reference signals, associated !ith +*/4' transmission

− UE$specific reference signals

/nchroni?ation signals

The snchroni?ation signals include the follo!ing t!o tpes of signals:

− 7rimar snchroni?ation signal

− /econdar snchroni?ation signal

4or 4.., the primar snchroni?ation signal maps to the last O4.+ smbol of the time

slot 0 and time slot )0# The secondar snchroni?ation signal maps to the second last

O4.+ smbol of the time slot 0 and time slot )0#

The uplin" phsical signals include the reference signals#

%eference signals

The uplin" reference signals include the follo!ing t!o tpes of signals:

− .emodulation reference signals, associated !ith 7U/C@ or 7UCC@ transmission

− /ounding reference signals, not associated !ith 7U/C@ or 7UCC@ transmission

The demodulation reference signals and the sounding reference signals use the same base

se5uence set#

(.7 +=4sical La4er Model

The follo!ing figures sho! the phsical laer models of various tpes of channels# 'ode

*s in all of the follo!ing figures are called e'ode*s or e'ode* in LTE#

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7hsical laer model for UL$/C@ transmission

(.> +=4sical La4er +rocedures

(.>.1 %4nc=roniation +rocedures

Cell search

Cell search is the procedure b !hich a UE ac5uires time and fre5uenc snchroni?ation

!ith a cell and detects that cells phsical laer cell


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LTE Overvie!

Uplin" po!er control procedure controls the transmit po!er of different uplin" phsical

channels#

.o!nlin" po!er allocation

e'ode* determines the do!nlin" transmit energ per resource element#

(.>.' -andom ccess +rocedures

7rior to initiation of the non$snchroni?ed phsical random access procedure, phsical

laer shall receive the follo!ing information from the higher laers:

)# %andom access channel parameters (7%&C@ configuration, fre5uenc position,and preamble format#

# 7arameters for determining the root se5uences and their cclic shifts in the

preamble se5uence set for the cell (inde; to root se5uence table, cclic shift

('cs, and set tpe (normal or high$speed set#

4rom the phsical laer perspective, the phsical random access procedure encompasses

the transmission of random access preamble and random access response# The remaining

messages are scheduled for transmission b the higher laer on the shared data channel

and are not considered part of the L) random access procedure#

The follo!ing steps are re5uired for the phsical random access procedure:

)# 7hsical laer procedure is triggered upon re5uest of a preamble transmission b

higher laers#

# & preamble inde;, preamble transmission po!er

(7%E&+*LEFT%&'/+


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3# & single preamble transmission then occurs using the selected preamble se5uence

!ith transmission po!er 7%E&+*LEFT%&'/+


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5 La4er 2

Laer consists of three sublaers 7.C7, %LC, and +&C# 4igure 9 and 4igure

respectivel sho! Laer do!nlin" and uplin" structures#

Laer do!nlin" structure

3


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Laer uplin" structure

The connection points among sublaers are "no!n as the /ervice &ccess 7oints (/&7#

The service provided b 7.C7 is referred to as the radio bearer# The 7.C7 provides the

%obust @eader Compression (%O@C and securit protection# The /&7 bet!een

phsical laer and +&C laer provides transport channels and that bet!een +&C laer

and %LC laer provides logical channels#

The +&C laer provides multiple;ing and mapping of logical channels (radio bearer to

transport channels (transport bloc"#

Onl one transport bloc" is generated at each TT< () ms in the uplin" or do!nlin" in thecase of non$+


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· +apping bet!een logical channels and transport channels#

· +&C /ervice .ata Unit (/.U multiple;ingBdemultiple;ing#

· /cheduling information report#

· Error correction through @&%A

· Logical channel prioriti?ation of the same UE#

· UE prioriti?ation through dnamic scheduling#

· /election of transmission formats#

· 7adding#

5.1.2 Logical C=annels

+&C provides different tpes of data transmission services# The tpe of each logical

channel is defined based on the tpe of transmitted data#

Logical channels are categori?ed into:

· Control channels: used to transfer data on the control plane#

· Traffic channels: used to transfer data on the user plane#

Control channels include:

· *roadcast Control Channel (*CC@#

The *CC@ is a do!nlin" channel used to broadcast sstem control messages#

· 7aging Control Channel (7CC@#

The 7CC@ is a do!nlin" channel used to transfer paging messages and sstem

information change notifications# The 7CC@ is used to page a UE !hen the UE

cell location is un"no!n to the net!or"#

· Common Control Channel (CCC@#

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The CCC@ is used to transfer control messages bet!een UEs and net!or" !hen

there is no %%C connection bet!een them#

· +ulticast Control Channel (+CC@#

& point$to$multipoint do!nlin" channel used for transmitting +*+/ control

information from the net!or" to the UE, for one or several +TC@s# This channel

is onl used to UEs that receive +*+/#

· .edicated Control Channel (.CC@#

& point$to$point bi$directional channel that transmits dedicated controlinformation bet!een a UE and the net!or"# This channel is used b UEs having

an %%C connection#

·Traffic channels include:

· .edicated Traffic Channel (.TC@#

The .TC@ is a point$to$point channel, dedicated to one UE, for the transfer of

user information#

· +ulticast Traffic Channel (+TC@#

& point$to$multipoint do!nlin" channel for transmitting traffic data from the

net!or" to the UE# This channel is onl used to UEs that receive +*+/#

5.1.' Mapping Between Logical C=annels and Transport C=annels

4igure 10 and 4igure 1) respectivel sho! the mapping bet!een do!nlin" and uplin"

logical channels and transport channels#

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+apping bet!een do!nlin" logical channels and transport channels

+apping bet!een uplin" logical channels and transport channels

5.2 -LC %ubla4er

5.2.1 -LC )unctions

The %LC sublaer provides the follo!ing functions:

· Transfer of upper laer 7.Us#

· Error Correction through &%A (onl for &+ data transfer#

· Concatenation, segmentation and reassembl of %LC /.Us (onl for U+ and

&+ data transfer#

· %e$segmentation of %LC data 7.Us (onl for &+ data transfer#

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·


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6 --C

6.1 --C )unctions

+ain 4unctions of %%C include:

· *roadcast of sstem information related to the '&/s

· *roadcast of sstem information related to the &/s

· 7aging

· Establishment, retention, and release of %%C connection bet!een UEs and E$

UT%&'s, including:

− &llocation of temporar identifiers bet!een UEs and E$UT%&'s

− Configuration of the /ignaling %adio *earers (/%*s for %%C connection

♦ Lo! priorit and high priorit /%*s

· /ecurit management including "e management

· Establishment, configuration, retention, and release point$to$point %*s

· +obilit management, including:

− +easurement report and reporting control of the mobile UEs bet!een cells

and bet!een %&Ts#

− @andover

− UE cell selection and reselectionM cell selection and reselection control

− Conte;t for!arding during handover

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· +*+/ notification

· Establishment, configuration, retention, and release of %*s for the +*+/

· Ao/ management

· UE measurement report and reporting control

· '&/ direct transfer

6.2 --C %tate

%%C state includes %%CF


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− The net!or" can transmit and receive data toBfrom the UEs#

− 'et!or" controlled mobilit (handover#

− 'eighbor cell measurements#

− The 7.C7B%LCB+&C features of the %%CFCO''ECTE.

♦ The UE can transmit and receive data toBfrom the net!or"s#

♦ The UE intercepts controlled signaling channels related to the shared data

channels to vie! that !hether the UE is allocated an data on the shared

data channel#

♦ The UE also reports channel 5ualit information and feeds bac"

information to e'ode*#

♦ The .%> ccle can be conformed according to the UE mobilit level to

save UE po!er and enhance resource efficienc# This function is

controlled b e'ode*#

6.' % %tate and t=e -elations=ip !it= t=e --C state

The '&/ state model can be described b the t!o$dimensional state model of the E7/

+obilit +anagement state (E++ and the E7/ Connection +anagement state#

· E++ state:

− E++$.E%E=


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'ote: The E++ state and the EC+ state are mutuall independent#

The relationship bet!een the '&/ state and the %%C state is as follo!s:

· E++$.E%E=


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information bloc"s#

· /stem


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· %%C connection establishment

·


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7 Core LTE Tec=nologies

7.1 "uple; Mode


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+ultiple;ing scheme in LTE uplin" sstems

7.' Multi$antenna Tec=nologies

.o!nlin" multi$antenna transmission:

+ulti$antenna transmission supports t!o or four antennas# The ma;imum number of

code !ords is and irrelevant of the number of antennas, but there is a fi;ed mapping

relationship bet!een core !ords and laers# 4igure 13 sho!s the general relationship

among code !ords, laers, and antenna ports#

7hsical channel processing

+ulti$antenna technologies include the /.+ and transmit diversit# The /.+ supports

/U$+


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transmitting on a single antenna, is supported#

Closed loop tpe adaptive antenna selection transmit diversit shall be supported for

4.. (optional in UE#

7.( Link daptation

.o!nlin" adaptation:

%efer to the adaptive modulation and coding (&+C that is applied !ith three

modulation schemes (A7/N, )6A&+, and 62A&+ and variable code rates#

Uplin" adaptation:


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·


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7.5.' 8-A0-A :nteractions


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> bbreviations

&bbreviation 4ull 'ame

1=77 1rd =eneration 7artnership 7roject

*7/N *inar 7hase /hift Neing

C&7E> Capital E;penditure

.4T .iscrete 4ourier Transform

.%> .iscontinuous %eception

E$+*+/ Evolved +ultimedia *roadcast and +ulticast /ervice

e'ode* Evolution 'ode *

E1= evolved 1=

E7C Evolved 7ac"et Core

E$UT%& Evolved Universal Terrestrial %adio &ccess

@C% @igh Chip %ate

@e'* @ome e'ode*


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? -eerences

/' 'ame

)3#) 4easibilit stud for evolved Universal Terrestrial %adio &ccess (UT%& and

Universal Terrestrial %adio &ccess 'et!or" (UT%&'

3#)1 %e5uirements for Evolved UT%& (E$UT%& and Evolved UT%&' (E$UT%&'

116#100 Evolved Universal Terrestrial %adio &ccess (E$UT%& and Evolved Universal

Terrestrial %adio &ccess 'et!or" (E$UT%&', Overall description

2 3#9)2 7hsical laer aspects for evolved Universal Terrestrial %adio &ccess (UT%&

3 16#)) 7hsical Channels and +odulation

6 16#) +ultiple;ing and channel coding

8 16#)1 7hsical laer procedures

9 16#)2 7hsical laer G +easurements

16#10 /ervices provided b the phsical laer

)0 16#11) %adio %esource Control (%%C

)) 16#)02 *ase /tation (*/ radio transmission and reception

) 16#1) +edium &ccess Control (+&C protocol specification

)1

1#20) =eneral 7ac"et %adio /ervice (=7%/ enhancements for Evolved Universal

Terrestrial %adio &ccess 'et!or" (E$UT%&' access

)2 1#01 7olic and charging control architecture

4.LTE Overview 69

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