lte overview 67
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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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1# %adio 8rotocol &rchitecture################################################################################################################)4
1##) Control 8lane 8rotocol &rchitecture####################################################################################)4
1## User 8lane 8rotocol &rchitecture#########################################################################################)7
1#1 /)
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3#1#) 8.C8 5unctions###################################################################################################################2
3#1# 8.U /tructure######################################################################################################################24
# RR$.............................................................................................................................................................4%
#) %%C 5unctions####################################################################################################################################29
# %%C /tate############################################################################################################################################30
#1 '&/ /tate and the %elationship -ith the %%C state##########################################################################3)
#2 %%C 8rocedure####################################################################################################################################3
#2#) /stem
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1 Overview
Knowledge points
+obile communications development
-C.+& evolution
T.$/C.+& evolution
C.+&000 evolution
1.1 Background
1.1.1 Mobile Communications Evolution
The development histor from = and 1= to 1#9 = is the development histor from lo!$
speed voice services to high$speed multimedia services of mobile communications#
1=88 has been progressivel perfecting LTE %7 standard:
)# LTE %7 %&') !as fro?en in .ecember 007#
# LTE %7 %&', %&'1, and %&'2 !ere fro?en in .ecember 007##
1# LTE %7 standard !as complete b +arch 009, implementing basic LTE
functions at the first commercial use of LTE sstems#
5igure )#) $) sho!s the development and evolution of !ireless communication
technologies#
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5igure )#)$) .evelopment and evolution of !ireless communication technologies
1.1.2 Comparison mong !C"M# T"$%C"M# and C"M2&&&
Table )#)$)Comparison among -C.+&, T.$/C.+&, and C.+&000
/tandard -C.+& C.+&000 T.$/C.+&
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Chapter 4 Core LTE Technologies
5igure )#)$ -C.+& technolog roadmap
1.1.( T"$%C"M Evolution
DTE !ireless net!or" e6uipment supports smooth evolution of recent T. evolutionsoft!are#
T. evolution can be divided into t!o stages: standard stage of C.+& technologies and
that of O5.+& technologies#
The standard stage of C.+& technologies can smoothl evolve to @/8& !ith
spectrum efficienc close to that of LTE#
Basic version
Short-term evolution version
Mid-term evolution version
Long-term evolution version (4G)
Phase I Phase II Phase III
C"M standard O)"M standard
'*++ ,-(/oice0"ata
1 2re3uenc4 point
'*++ ,-50607
8%+08%+9MBM%0Multi$Carrier
'*++ LTEO)"MM:MO
:MT$dv
5igure )#)$1 T.$/C.+& evolution
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1.1.5 C"M2&& Evolution
C.+& One is a collection of all
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Chapter 4 Core LTE Technologies
5igure )#$3 Organi?ation and establishment stages of 1=88 standards
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2 LTE :nde;es and -e3uirements
2.1 Overview
Knowledge points
/pectrum division
LTE sstem re6uirements
Others
8hsical channels and mapping relationship
5igure #) $ sho!s the LTE inde;es and re6uirements prescribed b 1=88#
5igure #)$ LTE inde;es and re6uirements
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2.2 )re3uenc4 Band "ivision
Table # $ lists the E$UT%& fre6uenc bands#
Table #$ E$UT%& fre6uenc bands
E$UT%&
Operating
*and
Uplin" (UL operating band */ receive
UE transmit
.o!nlin" (.L operating band */
transmit UE receive
.uple;
+ode
()L*!&w+ ()L*hi'h (,L*!&w+
(,L*hi'h
) )90 +@? G )970 +@? ))0 +@? G )40 +@? 5..
)730 +@? G )9)0 +@? )910 +@? G )990 +@? 5..
1 )4)0 +@? G )473 +@? )703 +@? G )770 +@? 5..
2 )4)0 +@? G )433 +@? ))0 +@? G )33 +@? 5..
3 72 +@? G 729 +@? 79 +@? G 792+@? 5..
710 +@? G 720 +@? 743 +@? G 773 +@? 5..
4 300 +@? G 340 +@? 0 +@? G 90 +@? 5..
7 770 +@? G 9)3 +@? 93 +@? G 90 +@? 5..
9 )429#9 +@? G )472#9 +@? )722#9 +@? G )749#9 +@? 5..
)0 )4)0 +@? G )440 +@? ))0 +@? G )40 +@? 5..
)) )24#9 +@? G )23#9 +@? )243#9 +@? G )300#9 +@? 5..
) 97 +@? G 4) +@? 47 +@? G 42 +@? 5..
)1 444 +@? G 474 +@? 42 +@? G 43 +@? 5..
)2 477 +@? G 497 +@? 437 +@? G 47 +@? 5..
H
)4 402 +@? G 4) +@? 412 +@? G 42 +@? 5..
###
11 )900 +@? G )90 +@? )900 +@? G )90 +@? T..
12 0)0 +@? G 03 +@? 0)0 +@? G 03 +@? T..
13 )730 +@? G )9)0 +@? )730 +@? G )9)0 +@? T..
1 )910 +@? G )990 +@? )910 +@? G )990 +@? T..
14 )9)0 +@? G )910 +@? )9)0 +@? G )910 +@? T..
17 340 +@? G 0 +@? 340 +@? G 0 +@? T..
19 )770 +@? G )90 +@? )770 +@? G )90 +@? T..
20 100 +@? G 200 +@? 100 +@? G 200 +@? T..
2.' +eak "ata -ate
The instantaneous do!nlin" pea" rate reaches )00 +bitBs (3 bitBsB@? at 0 +@?
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Chapter 4 Core LTE Technologies
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, +
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)# The user throughput per +@? at the 3J Cumulative .istribution 5unction (C.5
must reach t!o to three times the throughput of % @/.8
# The average user throughput per +@? must reach three to four times the
throughput of % @/.8
% @/.8& uses one transmitter one receiver ()T)% !hile LTE uses t!o transmitterBt!o
receiver (T%#
Uplin":
)# The user throughput per +@? at the 3J C.5 must reach t!o to three times the
throughput of % @/U8
# The user throughput per +@? must reach t!o to three times the throughput of %
@/U8
% @/U8& uses )T%, and so does LTE#
2.7 %pectrum Eicienc4
.o!nlin": On a net!or" !ith effective load, the target LTE spectrum efficienc(measured b the bit 6uantit per site, per @?, and per second is three to four times
more efficient than % @/U8 % @/.8& uses )T)% !hile LTE uses T%#
Uplin": On a net!or" !ith effective load, the target LTE spectrum efficienc (measured
b the bit 6uantit per site, per @?, and per second is t!o to three times more efficient
than % @/U8 % @/U8& uses )T%, and so does LTE#
2.> Mobilit4
E$UT%&' can provide optimum net!or" performance for mobile users at the speed of
0)3 "mBh, high performance services at the speed of )3)0 "mBh, and cell net!or"
services at the speed of )0130 "mBh (the speed even reaches 300 "mBh at specified
bands#
oice services and other realtime services provided in the % C/ domain are supported
b 8/ domain on the E$UT%&' and all these services can reach or e;ceed the 6ualit of
UT%&' services# The interrupt time caused b handovers !ithin the E$UT%& sstem
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Chapter 4 Core LTE Technologies
must be shorter than or e6ual to the handover time of the =E%&' C/ domain#
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)# E$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#
# The handover interrupt time bet!een E$UT%&' and =E%&' must be shorter
than 300 ms for non$realtime services#
4# 8aging information of onl one of the =E%&', UT%&, or E$UT%& sstems
needs to be monitored for multi$mode terminals in non$active state (similar to %
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' LTE rc=itecture
Knowledge points
%adio protocol structure
/) interface
> interface
'.1 %4stem rc=itecture
LTE adopts an O5.+$based air interface technolog !hich is different from those of
= and 1=# LTE adopts a flat net!or" architecture !ithin !hich E$UT%&' contains
onl e'ode*s instead of %'C, so as to optimi?e the traditional 1= net!or" architecture#
LTE supports functions of 8.C8B%LCB+&CBphsical laer protocols on the E$UT%&
user plane and functions of the %%C protocol on the control plane# 5igure 1#) $4 sho!s
the E$UT%&' sstem architecture#
5igure 1#)$4 E$UT%&' architecture
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e'ode*s are connected over an ; interface and ever e'ode* is connected to the
Evolved 8ac"et Core (E8C 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*# 5unctions 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, 8.C8, %%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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Chapter 4 Core LTE Technologies
5igure 1#)$7 5unctional split bet!een E$UT%&' and E8C
'.2 -adio +rotocol rc=itecture
'.2.1 Control +lane +rotocol rc=itecture
5igure 1# $9 sho!s the control plane protocol architecture#
5igure 1#$9 Control plane protocol stac"
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The 8.C8 terminates at e'ode* and implements functions such as control plane
encrption and integrit protection#
The %LC and +&C terminate at e'ode* on the net!or" side and implement identical
functions of the user plane and control plane#
The %%C terminates at e'ode* and implements such functions as broadcast, paging,
%%C connection management, %* control, mobilit, and UE measurement reporting and
control#
The '&/ terminates at ++E and implements such functions as E8/ bearer
management, authentication, idle$mode E8/ Connection +anagement (EC+, idle$mode
EC+ paging, and securit control#
'.2.2
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Chapter 4 Core LTE Technologies
'.'.1 %1 :nterace
The /) interface is defined as the interface bet!een the E$UT%&' and E8C# 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 /$=-#
5igure 1#1 $))and5igure 1#1 $) respectivel sho! the protocol stac" architecture of
the /)$++E interface and /)$U interface#
/CT8
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Chapter 4 Core LTE Technologies
The /) interface has the follo!ing ac"no!ledged signaling procedures:
E$%&* 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
8aging
'&/ 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
%eset
e'ode*$initiated reset
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++E$initiated reset
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Chapter 4 Core LTE Technologies
5igure 1#1$)1 $
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 >$C8 and >$U, !here the >$C8 is the control plane interface bet!een
e'ode*s and the >$U is the user plane interface bet!een e'ode*s# 5igure 1#1 $)2 and
5igure 1#1 $)3respectivel sho! the protocol stac" architecture of the >$C8 interface
and >$U interface#
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/CT8
interface user plane
The >$C8 has the follo!ing functions:
UE mobilit in the EC+$CO''ECTE. state !ithin the LTE sstem
Conte;t transfer from the source e'ode* to the target e'ode*
User plane channel control bet!een the source e'ode* and the target e'ode*
@andover cancellation
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Chapter 4 Core LTE Technologies
Uplin" load management
=eneral > interface management and error processing
Error indication
The >$C8 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#
5igure 1#1 $)sho!s that the LO&. , &8 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 5.. mode#
/tructure : &pplicable to the T.. mode#
5igure 2#) $)4 sho!s the frame structure )# Ever )0 ms radio frame is divided into ten
sub$frames of fi;ed length# Each sub$frame contains t!o time slots each of !hich is 0#3
ms long#
5igure 2#)$)4 5rame structure )
5or 5.., 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 fre6uenc 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$
fre6uenc domain phsical resources into %esource *loc"s (%*s for scheduling and
allocation#
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Chapter 4 Core LTE Technologies
5igure 2#$)9 8hsical resource structure of uplin" slot
(.' +=4sical C=annels
The do!nlin" phsical channels contain the follo!ing channels:
)# 8hsical *roadcast Channel (8*C@
The coded *C@ transmission bloc" maps to four sub$frames !ithin an 20 ms
interval#
The 20 ms timing is obtained b blind tests, namel, no specified signaling
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indicates the 20 ms timing#
-ith e;cellent$enough channels, ever sub$frame that the 8*C@ located can
separatel decode signals#
# 8hsical Control 5ormat
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Chapter 4 Core LTE Technologies
5igure 2#3$0 +apping bet!een do!nlin" transport channels and do!nlin" phsical channels
5igure 2#3$) +apping bet!een uplin" transport channels and uplin" phsical channels
(.6 +=4sical %ignals
8hsical 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:
Cell$specific reference signals, associated !ith non$+*/5' transmission
+*/5' reference signals, associated !ith +*/5' transmission
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UE$specific reference signals
/nchroni?ation signals
The snchroni?ation signals include the follo!ing t!o tpes of signals:
8rimar snchroni?ation signal
/econdar snchroni?ation signal
5or 5.., the primar snchroni?ation signal maps to the last O5.+ smbol of
the time slot 0 and time slot )0# The secondar snchroni?ation signal maps to the
second last O5.+ 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 8U/C@ or 8UCC@ transmission
/ounding reference signals, not associated !ith 8U/C@ or 8UCC@ transmission
The demodulation reference signals and the sounding reference signals use the
same base se6uence 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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C-C
-esource mapping
Coding 9 -M
"ata modulation
:nterleaving
MC
sc=eduler
Sin&le Transport blocks
(dynamic size S!
Node B
"eso#rce'poer
assi&nment
Mod#lation
sc)eme
Antennamappin&
ntenna mapping
C-C
-esource demapping
"ecoding 9 -M
"ata demodulation
"einterleaving
UE
ntenna demapping
Error
indication
C-C
-esource mapping
Coding 9 -M
"ata modulation
:nterleaving
MC
sc=eduler
Sin&le Transport blocks
(dynamic size S!
Node B
"eso#rce'poer
assi&nment
Mod#lation
sc)eme
Antennamappin&
ntenna mapping
C-C
-esource demapping
"ecoding 9 -M
"ata demodulation
"einterleaving
UE
ntenna demapping
Error
indication
5igure 2#4$2 8hsical laer model for 8C@ transmission
C-C
-B mapping
Coding 9 -M
"ata modulation
:nterl.
C-C
-esource mapping
Coding 9 -M
"ata modulation
:nterleaving
MC
sc=eduler
N Transport blocks
(dynamic size S1, SN!
Node B
"eso#rce'poer
assi&nment
Mod#lation
sc)eme
Antenna
mappin&
ntenna mapping
C-C
-B mapping
Coding 9 -M
"ata modulation
:nterl.
C-C
-esource demapping
"ecoding 9 -M
"ata demodulation
"einterleaving
UE
ntenna demapping
Error
indications
Semi-static
coniguration
C-C
-B mapping
Coding 9 -M
"ata modulation
:nterl.
C-C
-esource mapping
Coding 9 -M
"ata modulation
:nterleaving
MC
sc=eduler
N Transport blocks
(dynamic size S1, SN!
Node B
"eso#rce'poer
assi&nment
Mod#lation
sc)eme
Antenna
mappin&
ntenna mapping
C-C
-B mapping
Coding 9 -M
"ata modulation
:nterl.
C-C
-esource demapping
"ecoding 9 -M
"ata demodulation
"einterleaving
UE
ntenna demapping
Error
indications
Semi-static
coniguration
5igure 2#4$3 8hsical laer model for +C@ transmission
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Chapter 4 Core LTE Technologies
C-C
-B mapping
Coding 9 -M
"ata modulation
:nterl.
C-C
-esource demapping
"ecoding 9 -M
"ata demodulation
"einterleaving
MC sc=eduler
Node B
"eso#rceassi&nment
Mod#lationsc)eme
Antennamappin&
+A"Q in$oAK'NAK
ntenna demapping
C-C
-B mapping
Coding 9 -M
"ata modulation
:nterl.
C-C
-esource mapping
Coding 9 -M
"ata modulation
:nterleaving
8-A
UEError
indications
"eso#rce'po(erassi&nment
Mod#lationsc)eme
8-A
.2 +ower Control
8o!er control determines the energ per resource element (E8%E# E8%E denotes the
energ prior to C8 insertion# E8%E also denotes the average energ ta"en over all
constellation points for the modulation scheme applied# Uplin" po!er control determines
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the average po!er of one .5T$/O5.+ smbol on a phsical channel#
Uplin" po!er control
Uplin" po!er control procedure controls the transmit po!er of different uplin"
phsical channels#
.o!nlin" po!er allocation
e'ode* determines the do!nlin" transmit energ per resource element#
(.>.' -andom ccess +rocedures
8rior to initiation of the non$snchroni?ed phsical random access procedure, phsical
laer shall receive the follo!ing information from the higher laers:
)# %andom access channel parameters (8%&C@ configuration, fre6uenc position,
and preamble format#
# 8arameters for determining the root se6uences and their cclic shifts in the
preamble se6uence set for the cell (inde; to root se6uence table, cclic shift
('cs, and set tpe (normal or high$speed set#
5rom the phsical laer perspective, the phsical random access procedure encompasses
the transmission of random access preamble and random access response# The remaining
messages are scheduled for transmission b the higher laer on the shared data channel
and are not considered part of the L) random access procedure#
The follo!ing steps are re6uired for the phsical random access procedure:
)# 8hsical laer procedure is triggered upon re6uest of a preamble transmission b
higher laers#
# & preamble inde;, preamble transmission po!er
(8%E&+*LEFT%&'/+
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Chapter 4 Core LTE Technologies
ma;imum allo!ed po!er configured at higher laers, and 8L indicates UE$
calculated do!nlin" path loss#
2# & preamble se6uence is then selected from the preamble se6uence set using the
preamble inde;#
3# & single preamble transmission then occurs using the selected preamble se6uence
!ith transmission po!er 8%E&+*LEFT%&'/+
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5 La4er 2
Laer consists of three sublaers 8.C8, %LC, and +&C# 5igure 7 and 5igure 9
respectivel sho! Laer do!nlin" and uplin" structures#
5igure 2#7$4 Laer do!nlin" structure
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5igure 2#7$7 Laer uplin" structure
The connection points among sublaers are "no!n as the /ervice &ccess 8oints (/&8#
The service provided b 8.C8 is referred to as the radio bearer# The 8.C8 provides the
%obust @eader Compression (%O@C and securit protection# The /&8 bet!een
phsical laer and +&C laer provides transport channels and that bet!een +&C laer
and %LC laer provides logical channels#
The +&C laer provides multiple;ing and mapping of logical channels (radio bearer to
transport channels (transport bloc"#
Onl one transport bloc" is generated at each TT< () ms in the uplin" or do!nlin" in thecase of non$+
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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#
8adding#
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#
8aging Control Channel (8CC@#
The 8CC@ is a do!nlin" channel used to transfer paging messages and sstem
information change notifications# The 8CC@ 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
5igure 3#) $9and5igure 3#) $10respectivel sho! the mapping bet!een do!nlin"
and uplin" logical channels and transport channels#
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5igure 3#)$9 +apping bet!een do!nlin" logical channels and transport channels
5igure 3#)$10 +apping bet!een uplin" logical channels and transport channels
5.2 -LC %ubla4er
5.2.1 -LC )unctions
The %LC sublaer provides the follo!ing functions:
Transfer of upper laer 8.Us#
Error Correction through &%A (onl for &+ data transfer#
Concatenation, segmentation and reassembl of %LC /.Us (onl for U+ and
&+ data transfer#
%e$segmentation of %LC data 8.Us (onl for &+ data transfer#
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Transfer of user data#
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6 --C
6.1 --C )unctions
+ain 5unctions of %%C include:
*roadcast of sstem information related to the '&/s
*roadcast of sstem information related to the &/s
8aging
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$point %*s
+obilit management, including:
+easurement report and reporting control of the mobile UEs bet!een cells and
bet!een %&Ts#
@andover
UE cell selection and reselectionM cell selection and reselection control
Conte;t for!arding during handover
+*+/ notification
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Establishment, configuration, retention, and release of %*s for the +*+/
Ao/ management
UE measurement report and reporting control
'&/ direct transfer
6.2 --C %tate
%%C state includes %%CF
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The 8.C8B%LCB+&C features of the %%CFCO''ECTE.
The UE can transmit and receive data toBfrom the net!or"s#
The UE intercepts controlled signaling channels related to the shared data
channels to vie! that !hether the UE is allocated an data on the shared data
channel#
The UE also reports channel 6ualit information and feeds bac" information to
e'ode*#
The .%> ccle can be conformed according to the UE mobilit level to save UEpo!er and enhance resource efficienc# This function is controlled b e'ode*#
6.' % %tate and t=e -elations=ip !it= t=e --C state
The '&/ state model can be described b the t!o$dimensional state model of the E8/
+obilit +anagement state (E++ and the E8/ Connection +anagement state#
E++ state:
E++$.E%E=
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E++$%E=
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%%C connection release
%adio resource configuration
/%* additionB modification
.%* release
/%* additionB modification
+&C main reconfiguration
/emi$persistent scheduling reconfiguration
8hsical channel reconfiguration
%adio lin" failure related actions
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7 Core LTE Tec=nologies
7.1 "uple; Mode
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5igure 4#$12 +ultiple;ing scheme in LTE uplin" sstems
7.' Multi$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# 5igure 13 sho!s the general relationship
among code !ords, laers, and antenna ports#
5igure 4#1$13 8hsical channel processing
+ulti$antenna technologies include the /.+ and transmit diversit# The /.+ supports
/U$+
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%efer to the adaptive modulation and coding (&+C that is applied !ith three
modulation schemes (A8/P, )A&+, and 2A&+ and variable code rates#
Uplin" adaptation:
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@&%A operation in uplin" is governed b the follo!ing principles:
%egardless of the content of the @&%A feedbac" (&CP or '&CP, !hen a
8.CC@ for the UE is correctl received, the UE follo!s !hat the 8.CC@ as"s
the UE to do i#e# perform a transmission or a retransmission (referred to as
adaptive retransmission#
-hen no 8.CC@ addressed to the C$%'T< of the UE is detected, the @&%A
feedbac" dictates ho! the UE performs retransmissions#
'&CP: The UE performs a non$adaptive retransmission#
&CP: The UE does not perform an UL (retransmission and "eeps the data in the
@&%A buffer#
+easurement gaps are of a higher priorit than @&%A retransmissions:
-henever an @$&%A retransmission collides !ith a measurement gap, the @$
&%A retransmission does not ta"e place#
7.5.2 -A
The &%A !ithin the %LC sublaer has the follo!ing characteristics:
The &%A retransmits %LC /.Us or %LC 8.Us (segments#
&%A retransmissions are based on either %LC status reports or @&%AB&%A
interactions#
The %LC must poll %LC status reports#
/tatus reports can be triggered b upper laers#
7.5.' 8-A0-A :nteractions
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ppendi; bbreviations
&bbreviation 5ull 'ame
1=88 1rd =eneration 8artnership 8roject
*8/P *inar 8hase /hift Peing
C&8E> Capital E;penditure
.5T .iscrete 5ourier Transform
.%> .iscontinuous %eception
E$+*+/ Evolved +ultimedia *roadcast and +ulticast /ervice
e'ode* Evolution 'ode *
E1= evolved 1=
E8C Evolved 8ac"et Core
E$UT%& Evolved Universal Terrestrial %adio &ccess
@C% @igh Chip %ate
@e'* @ome e'ode*
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ppendi; B -eerences
/' 'ame
)3#9) 5easibilit stud for evolved Universal Terrestrial %adio &ccess (UT%& and
Universal Terrestrial %adio &ccess 'et!or" (UT%&'
3#9)1 %e6uirements for Evolved UT%& (E$UT%& and Evolved UT%&' (E$UT%&'
11#100 Evolved Universal Terrestrial %adio &ccess (E$UT%& and Evolved Universal
Terrestrial %adio &ccess 'et!or" (E$UT%&', Overall description
2 3#7)2 8hsical laer aspects for evolved Universal Terrestrial %adio &ccess (UT%&
3 1#)) 8hsical Channels and +odulation
1#) +ultiple;ing and channel coding
4 1#)1 8hsical laer procedures
7 1#)2 8hsical laer G +easurements
9 1#10 /ervices provided b the phsical laer
)0 1#11) %adio %esource Control (%%C
)) 1#)02 *ase /tation (*/ radio transmission and reception
) 1#1) +edium &ccess Control (+&C protocol specification
)1
1#20) =eneral 8ac"et %adio /ervice (=8%/ enhancements for Evolved Universal
Terrestrial %adio &ccess 'et!or" (E$UT%&' access
)2 1#01 8olic and charging control architecture
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