(19) United States
`(12) Patent Application Publication (10) Pub. No.: US 2007/0058595 A1
`Classon et al. Mar. 15, 2007 (43) Pub. Date:
`
`
`
`US 20070058595A1
`
`(54) NIETHOD AND APPARATUS FOR
`REDUCING ROUND TRIP LATENCY AND
`OVERHEAD WITHIN A COMMUNICATION
`SYSTEM
`
`App]. NO;
`
`11/276,981
`
`Filed:
`
`Mar. 20, 2006
`
`Related U.S. Application Data
`
`Provisional application No. 60/666,494, filed on Mar.
`30, 2005
`
`.
`e
`.
`'
`Publlcatlon Class1ficat10n
`
`(
`
`51)
`
`Int. (:1.
`H043
`(52) U.S. Cl.
`
`(2006.01)
`7/212
`.......................................... .. 370/337; 709/236
`
`SCHAUMBURG, [L 60196
`
`During operation radio frames are divided into a plurality of
`subframes. Data is transmitted over the radio frames Within
`
`(73) Assignee: MOTOROLA, INC: Schaumburg,
`(US)
`
`IL
`
`a plurality of subframes, and having a frame duration
`selected from two or more possible frame durations.
`
`(57)
`
`ABSTRACT
`
`SCHEDULABLE
`
`SHORT FRAME MULIIPLEX
`
`””“° " III-IIIIIIII
`
`Inventors: Brian K. Classon, Palatine, IL (US);
`Kevin L_ Baums Rolling Meadows, IL
`(US); Amitava Ghosh, Buffalo Grove,
`IL (US); Robert T. Love, Barrington,
`IL (Us); Vijay Nangia, Algonquin: IL
`(US); Kenneth A. Stewart, Grayslake,
`IL
`5
`(U)
`Correspondence Address:
`MOTOROLA. INC.
`1303 EAST ALGONQUIN ROAD
`IL01/3RD
`
`
`
`/ a
`
`s
`
`F
`wigs".st
`
`V‘IIIIIIII”‘IIIIIIIIV‘IIIIIIII
`0-5ms
`0-5ms
`COMMON PILOT
`E CONTROL
`III DATA
`
`A
`
`A
`
`PETITIONERS 1040-0001
`IPR2016-00758
`
`

`

`Patent Application Publication Mar. 15, 2007 Sheet 1 of 19
`
`US 2007/0058595 A1
`
`PETITIONERS 1040-0002
`IPR2016-00758
`
`

`

`El DATA
`
`
`
`/
`
`\
`
`13f
`,, /
`/ '\
`SUBiFRAME
`3 0an SYMBOLS
`
`\
`
`//
`
`Nrf SUB—FRAMES
`
`FIG. 3
`m
`
`SYMBOLS
`
`SCHEDULABLE
`UNI]. . .
`
`
`SHORT FRAME MULTIPLEX
`
`IIIIIIII”‘IIIIIIIIV‘IIIIIIII
`A.
`A;
`
`0.5ms
`0.5ms
`
`SHORT FRAME
`(0.5ms)
`
`COMMON PILOT
`E CONTROL
`
`FIG- 4
`
`Patent Application Publication Mar. 15, 2007 Sheet 2 of 19
`
`US 2007/0058595 A1
`
`50’
`
`RADIO FRAME (10ms)
`
`PETITIONERS 1040-0003
`IPR2016-00758
`
`

`

`0.5ms
`
`0.5ms
`
`LONG
`
`0.5ms
`
`(Ems)
`
`0.5ms
`
`DCOMMON PILOT SYMBOL
`
`E CONTROL SYMBOL
`
`DATA SYMBOL
`
`FIG. 5
`
`
`
`Patent Application Publication Mar. 15, 2007 Sheet 3 of 19
`
`US 2007/0058595 A1
`
`SCHEDULAHLE
`UNIT \
`
`0.5ms
`
`LONG FRAME MULTIPLEX
`
`LONG FRAME CONFIGURATION
`PARAMETER
`
`RADIO FRAME DURATION ms
`SUBFRAMES / RADIO FRAME
`SUBFRAME DURATION ms
`SUBFRANES / LONG FRAME
`LONG FRAME DURATION ms
`
`FIG. 6 EXEMPLARY LONG FRAME CONFIGURATIONS vs. SUBFRAME DURATION
`
`PETITIONERS 1040-0004
`IPR2016-00758
`
`

`

`Patent Application Publication Mar. 15, 2007 Sheet 4 of 19
`
`US 2007/0058595 A1
`
`70170,
`
`702RADIO FRAME CONSTRUGTED FROM SHORT FRAMES
`
`SHORTRAMES /
`
`"
`
`; RADIO FRAME n—1 E RADIO FRAME n
`
`RADIO FRAME n+1
`
`SYNCHRONISATION AND
`CONTROL REGION /
`/
`RADIO FRAME CONSTRUCTED FROM LONG FRAMES
`
`/ RADIO FRAME (TOms)
`
`FIG. 8
`
`RADIO FRAME n-1 RADIO FRAME n I RADIO FRAME n+1//
`, /
`RADIO FRAME (10ms)
`\ \ \ \
`
`RADIO FRAME CONSTRUCTED FROM LONG FRAMES ‘ \ \ \ \
`/ ’
`
`\\
`
`\\
`
`703
`
`LONG FRAME
`
`E CONTROL SYMBOL
`
`FIG. 7
`
`LONG FRAME
`
`OR
`
`RADIO FRAME GONSTRUCTED FROM LONG FRAMES
`
`SHORTRAMES
`
`LONG FRAME
`
`ECONTROL SYMBOL
`
`SHORT FRAMES
`
`|:|
`
`LONG FRAMES
`
`PETITIONERS 1040-0005
`IPR2016-00758
`
`

`

`Patent Application Publication Mar. 15, 2007 Sheet 5 of 19
`
`US 2007/0058595 A1
`
`CYCLIC
`PREFIX
`
`9m
`
`I
`
`PAYLOAD
`
`50.56ps<—>
`44.44ps
`
`NORMAL SUB-FRAME
`
`10 OFDM SYMBOLS
`
`IIIIIIIIII
`
`/
`
`50.0ps
`
`BROADCAST SUB-FRAME
`
`CYCLIC
`PREFIX
`W
`
`’
`I PAYLOAD
`
`11.11pshm.“s
`
`9 OFDM SYMBOLS
`IIIIIIIII
`55.56113
`
`PETITIONERS 1040-0006
`IPR2016-00758
`
`

`

`25
`
`0.625
`
`25
`
`40.00
`10.00
`
`40.00
`5.45
`
`10.00
`1.67
`
`40.00
`10.51
`11
`
`46.2963
`1000
`6.30
`12
`
`10.00
`2.74
`13
`
`40.00
`8.08
`13
`
`40.00
`4.64
`14
`
`40.00
`1.67
`15
`
`40.00
`7.62
`14
`
`TABLE 3 — FURTHER EXEMPLARY SUBFRAME CONFIGURATIONS vs. THE NUMBER OF
`OFDM SYMBOLS PER SUBFRAME AND SUBFRAME DURATION
`
`SUBFRAME CONFIGURATION
`PARAMETER
`
`RADIO FRAME 00101100
`1115
`10
`10
`10
`10
`10
`SUBFRAMES / RA010 FRAME
`16
`15
`15
`15
`SUBFRAME DURAIION m6
`0.55556 0.625
`0.66667 0.66667 0.66667
`SUBCARRIER SPACING kHz
`25
`25
`25
`SYMBOL DURATION us
`USEFUL (us)
`GUARD (us)
`SYMBOLS PER SUBFRAME
`
`
`
`Patent Application Publication Mar. 15, 2007 Sheet 6 of 19
`
`US 2007/0058595 A1
`
`
`
`
`
`“5 fl%flflflflfl
`SUBFRAMES / RADIO FRAME
`7 J 20
`18
`15
`15
`15
`SUBFRAIIE DURMION ms mmmmm
`SUBCARRIER SPACING kHz 21% 22.5
`22.5
`22.5
`SYMBOL DURATION us mm
`mm us
`GUARD
`SYMBOLS PER SUBFRAME
`
`13
`12
`11
`12
`11
`10
`11
`10
`9
`TABLE 2 - EXEMPLARY SUBFRAME CONFIGURATIONS vs. THE NUMBER OF OFDM
`SYMBOLS FER SUBFRAME AND SUBFRAME DURATION.
`
`FIG- 11
`
`
`
`
`
`
`
`40.00
`4.44
`15
`
`40.00
`21.67
`16
`
`
`
`PETITIONERS 1040-0007
`IPR2016-00758
`
`

`

`EXAMPLE: 2/3 RADIO FRAME ALLOCATED TO BROADCAST
`
`/
`
`\\
`
`EXAMPLE: ENTIRE RADIO FRAME ALLOCATED TO BROADCAST! /
`\\
`/
`/
`
`RADIO FRAME n—1
`
`RADIO FRAME n
`
`RADIO FRAME n+1
`
`' - -
`
`BROADCAST FRAME
`
`|:| UNICAST FRAME
`
`ESYNCHRONIZATION AND CONTROL REGION
`
`Patent Application Publication Mar. 15, 2007 Sheet 7 of 19
`
`US 2007/0058595 A1
`
`NORMAL SUB-FRAME
`
`BROADCAST SUB-FRAME
`
`\
`
`50.0“;
`/
`
`LONG FRAME
`
`\
`
`/
`
`III-.- III...
`EXAMPLE: 1/3 RADIO FRAME ALLOCATED TO BROADCAST
`
`FIG. 12
`
`PETITIONERS 1040-0008
`IPR2016-00758
`
`

`

`I g £50.05:
`
`\
`
`RADIO FRAME n-1
`
`RADIO FRAME n
`
`RADIO FRAME n+1
`
`- - -
`
`% BROADCAST FRAME
`
`|:| UNICAST FRAME
`
`ESYNCHRONIZATION AND CONTROL REGION
`
`Patent Application Publication Mar. 15, 2007 Sheet 8 of 19
`
`US 2007/0058595 A1
`
`NORMAL SUB-FRAME
`
`/
`
`_ %I%I%I%I%I%.
`
`FIG- 13
`
`PETITIONERS 1040-0009
`IPR2016-00758
`
`

`

`mSHORT FRAMES
`|:| LONG FRAME
`ESYNCHRONIZATION AND CONTROL REGION
`ljsua—ERAME
`ELL SYNCHRONIZATIUN SYMBOL
`LOBAL SYNCHRONIZATION SYMBOL
`OMMON PILOT
`
`55.56;“
`
`Patent Application Publication Mar. 15, 2007 Sheet 9 of 19
`
`US 2007/0058595 A1
`
`RADIO FRAME CONSTRUCTED FROM SHORT [I LONG FRAMES
`
` W
`
`Z
`
`§§
`\
`\LTTmm“
`L\T\T\\L\L\T\
`“\Tumm T\T\T\\m\u
`\\TT\\L\L\T\
`\\\\\\\l\\\‘\
`“Numm mumum
`\\TN\\\\\T\
`\\\\\\\m\\\
`\\\\\\\\m\
`|\\\“\N\V\
`“\Tumm I\T\T\\L\L\T\
`\mumm \\\\\\\l\\\‘\
`
`/
`m
`“\\\\\V\\\\ mmm
`“\muu“ \\\\u\\\\\\
`\\\\\\\\\V\\
`T\\L\L\TT\A\
`wauu T\TT\TL\\T\\
`T\\L\L\TT\\\
`\\\\\\\\\\\\
`T\\L\L\TT\\\
`\\\\\L\\\Y\
`T\\L\L\T\\\\
`\\\\\\\\\\\\
`mmwm Tmumm
`
`
`
`:
`I
`
`LONG FRAME
`
`I
`
`/
`\m
`T\T\TTT\\\\\\ mmm
`ALLTuumL \meLLTu
`T\'.\Tm\\\\\ T‘.\\\\\\L\TT\
`A\'.\“\\\\\\\ mnmmu
`\\'A\\\\\\\\\ TL\T\T\\NTT\
`T\L\Tm\\\\\
`\L\\\\\\l\\\\
`ALL\\\\\\\\L \meLmT
`.\'.\\TTL\\\\\ TmeLmL
`
`CONTROL
`DATA
`‘ CH - PACINC CHANNEL INFORMATION
`A
`DCCH - BROADCAST CONTROL CHANNEL INFO
`
`|]]]]]]]RI — PAGING INDICATORS
`AI — ACKNOWLEDGEMENT INDICATORS
`flu - OTHER INDICATORS (NOT SPECIFIED)
`BI — BROADCAST INDICATORS
`
`PETITIONERS 1040-0010
`IPR2016-00758
`
`

`

`
`
`
`
`
`
`CONTROL
`
`PCH - PAGINC CHANNEL INFORMATION
`— BROADCAST CONTROL CHANNEL INFO
`PACING INDICATORS
`ACKNOWLEDGEMENT INDICATORS
`
`OTHER INDICATORS (NOT SPECIFIED)
`BROADCAST INDICATORS
`
`[MSHORF FRAMES ESYMOHROMIZATIOM AND CONTROL REOIOM
`|:|LONO FRAME
`|:|suB-FRAME
`OELL SYNCHRONIZATION SYMBOL
`GLOBAL SYNCHRONIZATION SYMBOL
`COMMON PILOT
`
`
`
`Patent Application Publication Mar. 15, 2007 Sheet 10 of 19
`
`US 2007/0058595 A1
`
`RADIO FRAME i CONSTRUCTED FROM SHORT a LONG FRAMES
`
`
`\ \
`M v
`\\\Mwm \\\mwuu
`\mnmm \\\mwuu
`\Mmmnu \\\mmuu
`\mnmm \\\mwuu
`\mnmw \\\mmuu
`wmmv \\\mwuu
`mumm-
`\\\mmm
`
`\\\
`.
`\\L\T\\\\'\\L
`\\L\L\\\\v\\\
`mwvmv.
`\\\MNNT‘ mum-\\\
`\\mwmv.
`\\L\T\\\\'\\L
`\\\\L\\\\I\\\
`\\vuwuw.
`\\L\\L\V\\\\L \\m\\\\v\\A
`\\TMNNV, \\mmum
`
`\\
`\
`R
`\\\mu~\\\\ \\\mmu“
`\\\mumu “\\\mw“
`\\\mumu \mmuvu
`\\\m\\'\\\\ \\\mmv“
`\mwvuu \\\mxmvn
`\\\mmuu \\\mmm
`\\\numu \\\m\\\\-\\
`
`LONG FRAME
`
`RADIO FRAME i+1
`
`A \
`
`\\\u M“ \\L\\\\\\\\
`
`\mem“ “mum
`\T\\\\\\V\\\ umva
`w“an \\mmm
`\L\\\\\m\\ “\\NMW
`“\\\um“ mmmw
`\L\\\\\u\\\ \\mwm
`\meme \\mmm
`
`SYHCHRONIMON
`AND CONTROL
`RECION (EVERY
`Rh RADIO FRAMU
`
`
`
`PETITIONERS 1040-0011
`IPR2016-00758
`
`

`

`MSHORT FRAMES
`|:|LONO FRAME
`ESYNOHRONIZAHON AND CONTROL REOION
`[ISUB-ERANE
`SUPER FRAME CONTROL REOION
`
`SUPER FRAME k
`
`SUPER FRAME i
`
`SUPER FRAME i+1
`“‘ \
`
`-°°
`
`RADIO FRAME n-1
`
`RADIO FRAME:
`SYNCHRONIZAHON AND
`CONTROL REGION
`
`/
`
`RADIO ERANE (IOms)
`
`/ R
`
`Patent Application Publication Mar. 15, 2007 Sheet 11 of 19
`
`US 2007/0058595 A1
`
`H-
`
`SUPER FRAME i-1
`4’
`
`SUPER ERANE-
`CONTROL REGION
`
`
`ADIO FRAME CONSIRUCTED FROM SHORT AND LONG FRAMES \
`
`SHORTFRAMES
`
`LONG FRAME
`
`FIG. 16
`
`PETITIONERS 1040-0012
`IPR2016-00758
`
`

`

`UPER FRAME k
`
`
`
`Patent Application Publication Mar. 15, 2007 Sheet 12 of 19
`
`US 2007/0058595 A1
`
`SUPER FRAME i
`
`SUPER FRAME i+1
`‘
`
`SYNC'E.§%I,.‘}Z§'§§3§ AND
`CONTROL REGION
`
`SUPER FRAME i—l
`/
`
`SUPER FRAME:
`CONTROL REGION
`
`..R. M
`“mm
`mmw R
`mm“
`
`H, H,
`
`UUUUUU
`wwmw
`mum“
`“mum
`“mm
`mme
`
`wmw
`R
`
`SHORT FRAMES
`
`LONG FRAME
`
`MSHORI FRAMES
`|:|LONO FRAME
`ESYNOHRONIZATION AND CONTROL REOION
`DSUB—FRAME
`A??? SUPER FRAME CONTROL REGION
`
`PETITIONERS 1040-0013
`IPR2016-00758
`
`

`

`SUPER FRAME k
`
`‘
`
`Patent Application Publication Mar. 15, 2007 Sheet 13 of 19
`
`US 2007/0058595 A1
`
`RADIO FRAME CONSTRUCTED FROM SHORT & LONG FRAMES
`
`
`T.
`SYNCHRONIZATION
`AND CONTROL
`REGION
`
`x
`
`\
`\\\\\A\\ \muwm
`\\\\\N\\ \muwm
`\\\\\\\\
`\\\\N\\T\\\
`\\\\\A\\ \mmum
`mum mum“
`\\\\\A\\ mum“
`\\A\\\\\V\\A \T\\\\\\T\\\
`\\A\\\\\\A\\ mum-m
`
`SHORT FRAMES
`\V\\\\\
`'
`\\\\\V\\\\\
`T
`\\\\\\\\A\\
`
`'
`
`FR '
`OFFSET
`
`/_
`
`_, [J’—
`'
`'
`A
`'
`\
`\\A\T\V\\A\\\ \mumm
`\\\\T\I\\\\\\ M\\\T\V\\T\\
`\\|\\\\\\\\T\
`\A\A\T\m\\\
`A\T\T\N\\\T\ vmumm
`\\\\T\\\\A\\\
`\A\\\\\V\\\\\
`\\A\T\T\\\\\\ “\NNmm
`\
`.
`.
`A
`
`'
`.
`\\\\\\'.\T\\\\ T\\\\A\\\\\v\
`\T\\\\T\T\\\\ T\N\A\\\\\\\
`\\\\\\T\T\\A\
`\\\\\T\\\\\\A
`\U\\\'.\T\\l\
`\\\\\A\\\\\\\
`\\\\\\'.\\\\\\ \\\\\A\\\\\\A
`\\\\\\'.\T\\A\ T\\\\T\\\\\\N
`.
`T
`
`LONG FRAME
`A\T\T\\T\\u\
`\\\'.\T\\\\‘T\\
`A\T\V\\\\\\V\
`\\\'.\T\\\\\N
`A\\\\\\\\\U
`.
`T
`\\T\T\\mu
`A\\\\\\\\\\V\
`\\\'.\T\\\\T\T
`mmmm \\v.\T\\\\m
`\\T\V\\\\\\V\
`\\\'.\T\\\\m
`mmmm \\\'.\T\\A\T\\
`
`\T\\w\\\\\\
`‘\\\\\\\\T\\
`\\\\\\A\\\\\\
`T\\\\\\T\T\\\
`T\\A\\\T\T\\A \\\\\\u\\\\\
`v\\\\\\\\T\\\ TT\N\A\\\\\\
`V\\\\\\'.\\\\A \T\\T\\\\\\\\
`I\\\\\\'.\T\\A “\wmm
`‘\\\\\\'.\T\\\ \\\\\\T\\\\\\
`vummm \\\\\\A\\\\\\\
`
`~\
`
`ONE DOWNLINK AND UPLINK RADIO FRAME STRUCTURE
`
`FIG- 18
`
`MSHORT FRANEs
`ICOMMON PILOT
`|:|LONc FRANE
`ESYNCHRONIZATION AND CONTROL REGION CONTROL
`Elsua—FRANE
`DATA
`3% SUPER FRAME CONTROL REGION
`
`PETITIONERS 1040-0014
`IPR2016-00758
`
`

`

`Patent Application Publication Mar. 15, 2007 Sheet 14 of 19
`
`US 2007/0058595 A1
`
`\
`\\\\\\\\L\\\
`\\\\\\T\\\\\
`\\\\\v\\\\\\
`\\\\\\N\\\\\
`\N\\\\T\w\\\ \\\\\\\\\\\\
`\\L\\\N\\\\L \\\\\vL\L\L\
`\\\\\\T\\\\\
`\\\\\V\\L\\\
`\\\\\\N\\\\\
`\\\\\T\\L\\\
`\N\\\\T\V\\\
`\\\\\V\\\\\\
`\\\\L\N\\\\L \\\\\vL\L\L\
`
`
`
`OFFSET
`
`LONG RACH LONG FRAME
`EVERY 100ms OTHERWISE
`OATA LONG FRAME
`
`g _
`Ig'i
`-;
`;
`
`
`SHORT RACH
`
`SUBFRAME
`
`ALTERNATIVE UPLINK FRAME STRUCTURE
`
`RAOH
`MSHORT FRAMES
`E] COMMON PILOT
`|:|LONO FRAME
`ESYNCHRONIZATION AND CONTROL REGION CONTROL
`DSUB—FRAME
`DATA
`SUPER FRAME CONTROL REGION
`
`FIG“ 1‘9
`
`
`RADIO FRAME CONSTRUCTED FROM SHORT & LONG FRAMES
`L.
`
`SYNCHRONIZATION
`ANU OONTROL
`REGION
`
`SUPER FRAME k
`
`PETITIONERS 1040-0015
`IPR2016-00758
`
`

`

`ALTERNATIVE UPLINK FRAME STRUCTURE
`
`RACH
`mSHORT FRAMES
`ONMON PILOT
`|:|LONG FRAME
`ESYNCHRONIZATION AND CONTROL REGION CONTROL
`|:|3UD—FRAME
`DATA
`SUPER FRAME CONTROL REGION
`
`SHORT RACH
`
`7 SHORT RAGH
`SUBFRAME
`
`RAGH GUARD
`
`RADIO FRAME CONSIRUCTED FROM SHORT & LONG FRAMES
`L
`
`SYNCHRONIZAIION
`AND CONTROL
`REGION
`
`UPER FRAME k
`
`Patent Application Publication Mar. 15, 2007 Sheet 15 of 19
`
`US 2007/0058595 A1
`
`
`
`\ \
`
`\\\A\L\TTTL H\V\\\\\\\\
`T\\T\L\TNN\ NT\N\\T\\\\\
`\\\\\L\‘\\\ NT\\\\L\\\\\
`\\TA\LUN\L TT\V\\A\\\T\
`mmm“ NT\\\\L\\\T\
`mmum \T\\\\L\\\\\
`T\\T\L\TN\\ NT\N\\T\\\\\
`\\\\L\Lm\\ TTmme
`
`FRAME
`
`OFFSET LONG RACH LONG FRAME
`EVERY 100ms OTHERWISE
`DATA LONG FRAME
`
`PETITIONERS 1040-0016
`IPR2016-00758
`
`

`

`
`
`SHORT RACH /
`SUBFRAME /
`RACH GUARD
`
`mSHORF FRAMES
`OMMON PILOT
`I:ILONG FRAME
`ESYMOHRONIZAHOM AND CONTROL REGION CONTROL
`|:| SUB—FRAME
`DATA
`SUPER FRAME CONTROL REcIOM
`
`Patent Application Publication Mar. 15, 2007 Sheet 16 of 19
`
`US 2007/0058595 A1
`
`REOIOM
`
`FRAME
`OFFSET
`
`RADIO FRAME CONSTRUCTED FROM SHORT & LONG FRAMES
`
`M
`STNCHRONIZATION
`AND cOMrROL
`
`SUPER FRAME k
`
`PETITIONERS 1040-0017
`IPR2016-00758
`
`

`

`US 2007/0058595 A1
`
`|:| UNALOWED
`SUB—CARRIER(S)
`
`COMMON PILOT SYMBOL
`
`CONTROL SYMBOL
`
`Patent Application Publication Mar. 15, 2007 Sheet 17 of 19
`
`
`
`PETITIONERS 1040-0018
`IPR2016-00758
`
`

`

`'—0BMVI5I.0TB0Mnuw“DI
`
`>ozm20mzm
`
`|:| UNALOCATED
`SUB-CARRIER(S)
`
`LN00RMTMN00CCA‘%&
`
`PETITIONERS 1040-0019
`IPR2016-00758
`
`

`

`>02m=0mmm
`
`%%%%%%%%%%%%%%%%%%%%%%%%%
`
`II
`
`
`
`IIIIIIIIIII-IIIIIIIII
`
`
`
`IIIIIIIIII-III...-
`
`
`
`IIIIIIIIII-III...-
`
`
`
`%%%%%%%,fi%%%%%%%%%%%%%
`
`%%%%%%%%Z%Z%%%%%%%%%%%%%
`
`III-IIIIIIIIIIIIIIIIIIII
`
`IIIIIIIIIII
`
`.-
`
`.-
`
`%%%%%%%%%%%%%%%%%%Z%%%%%%
`
`III-IIIIIIIIIIIIIIIIIIII
`
`IIlfl“
`
`III-IIIHIII
`
`r._mm
`
`91f091teehS7002591
`
`US 2007/0058595 A1
`
`COMMON PILOT SYMBOL
`
`5V CONTROL SYMBOLS
`
`FREQUENCY DIVERSE
`RESOURCE ALLOCATION
`
`FREQUENCY SELECTIVE
`RESOURCE ALLOCATION
`
`H0fiac.hbHPn0.nac.hPPAtnetaP
`
`PETITIONERS 1040-0020
`IPR2016-00758
`
`

`

`reducing round-trip latency Within a communication system.
`
`[0003] One of the key requirements for wireless broad-
`band system development, such as in the 3” generation
`
`partnership project (3GPP) Long Term Evolution (LTE), is
`reducing latency in order to improve user experience. From
`a link layer perspective,
`the key contributing factor to
`latency is the round-trip delay between a packet transmis-
`sion and an acknowledgment of the packet reception. The
`round—trip delay is typically defined as a number of frames,
`where a frame is the time duration upon which scheduling is
`performed. The rotmd-trip delay itself determines the overall
`automatic repeat request
`design, including design
`parameters such as the delay between a first and subsequent
`transmission of packets, or the number of hybrid ARQ
`channels (instances). A reduction in latency with the focus
`on defining the optimum frame duration is therefore key in
`developing improved user experience in future communica-
`tion systems. Such systems include enhanced Evolved Uni—
`versal Terrestrial Radio Access (UTRA) and Evolved Uni-
`versal Terrestrial Radio Access Network (UTRAN) (also
`known as EUTRA and EUTRAN) within 3GPP, and evolu-
`tions of communication systems within other technical
`specification generating organizations (such ‘Phase 2’ within
`3GPP2, and evolutions of IEEE 802.11, 802.16, 802.20, and
`802.22).
`
`
`
`FIG. 10 shows a ‘broadcast’ subframe comprised
`[0014:
`ofj=9 symbols each with a cyclic prefix 1001 of 11.11 as
`which may be used for broadcast transmission.
`
`FIG. 11 shows a table having examples of three
`[0015:
`subframe types.
`
`FIG. 12 shows a long frame composed entirely of
`[0016:
`broadcast subframes or composed entirely of normal (uni-
`cast) subframes.
`
`FIG. 13 shows a short frame composed of either a
`[0017:
`normal or a broadcast subframe and one or more broadcast
`type Siort frames.
`
`FIG. 14 shows an example of the radio frarne
`
`FIG. 15 shows an altemate Radio Frame structure
`of arbitrary size where the synchronization and control
`(S+C) region is not part of a radio frame but part of a larger
`hierarchical
`frame structure composed of radio frames
`where the (S+C) region is sent with every j Radio Frames.
`
`FIG. 16 and FIG. 17 illustrate a hierarchical frame
`[0020]
`structure where a Super frame is defined to be composed of
`11+] radio frames.
`
`FIG. 18 shows the uplink subframes to be of the
`[0021]
`same configuration as the downlink subframes.
`
`FIG. 19 through FIG. 21 show 2 ms long frames
`[0022]
`composed of 0.5 ms subframes that are of frame type long
`RACH, Data, or Composite.
`
`FIG. 22 through FIG. 24 show short frame fre-
`[0023]
`quency selective (FS) and frequency diverse (FD) resource
`allocations respectively for several users.
`
`
`
`DETAILED DESCRIPTION OF TIIE DRAWINGS
`
`In order to address the above-mentioned need, a
`[0024]
`method and apparatus for reducing round-trip latency is
`provided herein. During operation radio frames are divided
`into a plurality of subframes. Data is transmitted over the
`radio frames within a plurality of subframes, and having a
`frame duration selected from two or more possible frame
`durations.
`
`[0025] The present invention encompasses a method for
`
`
`
`
`[0004] Unfortunately, no single frame duration is best for
`dimerent traffic types requiring different quality of service
`(QoS) characteristics or offering differing packet sizes. This
`is especially true when the control channel and pilot over-
`head in a frame is considered. For example, if the absolute
`control channel overhead is constant per user per resource
`allocation and a single user is allocated per frame. a frame
`duration of 0.5 ms would be roughly four times less efficient
`than a frame duration of 2 ms. In addition, different frame
`durations could be preferred by different manufacturers or
`operators, making the development of an industry standard
`or compatible equipment dillicult. Therefore, there is a need
`for an improved method for reducing both round-trip latency
`and overhead within a communication system.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`[0005] FIG. 1 is a block diagram of a communication
`system.
`
`[0006] FIG. 2 is a block diagram of circuitry used to
`perform uplink and downlink transmission.
`
`[0007] FIG. 3 is a block diagram of a radio frame.
`
`US 2007/0058595 A1
`
`Mar. 15, 2007
`
`METHOD AND APPARATUS FOR REDUCING
`ROUND TRIP LATENCY AND OVERHEAD
`WITHIN A COMMUNICATION SYSTEM
`
`RELATED APPLICATIONS
`
`[0001] This application claims priority to U.S. Provisional
`Application Ser. No. 60/666,494 filed Mar. 30, 2005.
`
`
`
`FIELD OF TIIE INVENTION
`
`[0002] The present invention relates generally to commu-
`nication systems and in particular, to a method and apparatus
`for reducing round-trip latency and overhead within a com-
`munication system.
`
`
`
`BACKGROUND OF THE INVENTION
`
`FIG. 4 shows a sequence of consecutive short
`
`FIG. 5 shows a sequence of consecutive long
`
`FIG. 6 shows a table for a 10 ms radio frame and
`subframes of approximately 0.5 ms. 0.55556 ms, 0.625 ms.
`and 0.67 ms.
`
`FIG. 7 shows examples for the third data column of
`[0011:
`Table l, with 0.5 ms subframes and 6 subframes per long
`frame (3 ms).
`
`FIG. 8 shows two examples of radio frames based
`[0012:
`on a combination of 2 ms long frames and 0.5 ms short
`frames.
`
`FIG. 9 shows a subframe comprised ofj=10 OFDM
`[0013:
`symbols each with a cyclic prefix 901 of5.56 us which may
`be used for unicast transmission.
`
`PETITIONERS 1040-0021
`IPR2016-00758
`
`

`

`US 2007/0058595 A1
`
`Mar. 15, 2007
`
`[0030] A method for transmitting data within a commu-
`nication system. The method comprises the steps of deter—
`minng a carrier bandwidth and receiving data to be trans-
`mitted over a radio frame, where the radio frame is
`comprised of a plurality of subframes. A frame is selected,
`where the frame is substantially equal
`to a multiple of
`subframes and each subframe is comprised of resource
`elements, where a resource elenrent comprises multiples of
`sub-carriers such that a carrier bandwidth is divided into a
`number of resource elements. The data is placed within the
`multiple subframes to produce multiple subframes of data
`and the frame is transmitted having the multiple subframes
`of data and the subframe type over the radio frame,
`
`The method comprises the steps of receiving data to be
`transmitted over a radio frame, where the radio frame is
`comprised of a plurality of subframes. A frame duration is
`selected from two or more possible frame durations, where
`a frame is substantially equal to a multiple of subframes. The
`data is placed within the multiple subframes to produce
`multiple subframes of data, and the frame is transmitted
`having the multiple subframes of data over the radio frame.
`
`invention additionally comprises a
`[0026] The present
`method comprising the steps of receiving data to be trans-
`mitted to a first user over a radio frame, where the radio
`frame is comprised of a plurality of subframes. A frame
`duration is selected for the first user from two or more
`possible frame durations, where a frame is substantially
`equal to a multiple of subframes. The data for the first user
`is placed within the multiple subframes to produce multiple
`subframes of data and then transmitted to the first user
`having the multiple subframes of data over the radio frame.
`Second data is received to be transmitted to a second user
`over the radio frame. A second frame duration is selected for
`the second user from the two or more possible frame
`durations, where a second frame is substantially equal to
`multiple of subframes. The second data for the second user
`is placed within the multiple subframes to produce second
`multiple subframes of data, and the second frame is trans-
`mitted to the second user having the second multiple sub—
`frames of data over the radio frame.
`
`ted signal characteristics (e.g., R=1/4, 1/2, and 3/4 for QPSK;
`
`[0031] Turning now to the drawings, wherein like numer-
`als designate like components, FIG. 1 is a block diagram of
`communication system 100. Communication system 100
`comprises a plurality of cells 105 (only one shown) each
`having a base transceiver station (HTS, or base station) 104
`in communication with a plurality of remote, or mobile units
`101-103. In the preferred embodiment of the present inven-
`tion, communication system 100 utilizes a next generation
`Orthogonal Frequency Division Multiplexed (OFDM) or
`multicarrier based architecture, such as OFDM with or
`without cyclic prefix or guard interval (e.g., conventional
`OFDM with cyclic prefix or guard interval, OFDM with
`pulse shaping and no cyclic prefix or guard interval (OFDM/
`OQAM with IOTA (Isotropic Orthogonal Transform Algo-
`rithm) prototype filter), or single carrier with or without
`cyclic prefix or guard interval (e.g., IFDMA, DFT—Spread-
`OFDM), or other. The data transmission may be a downlink
`transmission or an uplink transmission. The transmission
`scheme may include Adaptive Modulation and Coding
`(AMC). The architecture may also include the use of spread—
`ing techniques such as multi-carrier CDMA (MC-CDMA),
`
`multi-carrier direct sequence CDMA (MC-DS-CDN'A),
`Orthogonal Frequency and Code Division Multiplexing
`(OFCDM) with one or two dimensional spreading, or may
`be based on simpler time and/or frequency division multi—
`plexing/multiple access techniques, or a combination of
`these various techniques. However,
`in alternate embodi-
`ments communication system 100 may utilize other wide-
`band cellular communication system protocols such as, but
`not limited to, TDMA or direct sequence CDMA.
`
`[0027] The present invention encompasses a method for
`transmitting data within a communication system. The
`method comprises the steps of receiving data to be trans-
`mitted over a radio frame, where the radio frame is com-
`prised of a plurality of subframes. A frame length is selected
`comprising multiple subframes and a subframe type is
`selected from one of two or more types of subframes for the
`multiple of subframes. The data is placed within the multiple
`subframes to produce multiple subframes of data and the
`frame is transmitted having the multiple subframes of data
`and the subframe type over the radio frame.
`
`[0028] The present invention encompasses a method for
`transmitting data within a communication system. The
`method comprises the steps of receiving data to be trans-
`mitted over a radio frame, where the radio frame is com-
`prised of a plurality of subframes. A frame is selected
`wherein the frame is substantially equal to a multiple of
`subframes. The data is placed within the multiple subframes
`to produce multiple subframes of data and a common pilot
`is placed within each subframe of the multiple subframes,
`The frame having the multiple subframes of data is trans-
`mitted over the radio frame.
`
`[0029] The present invention encompasses a method for
`transmitting data within a communication system. The
`method comprises the steps of determining a system band-
`width from two or more system bandwidths and receiving
`data to be transmitted over a radio frame and the system
`bandwidth. The radio frame is comprised of a plurality of
`subframes, and a radio frame duration and a subframe
`duration is based on the system bandwidth. A frame is
`selected, where a frame is substantially equal to a multiple
`of subframes. The data is placed within the multiple sub-
`frames to produce multiple subframes of data and the frame
`is transmitted having the multiple subframes of data and the
`subframe type over the radio frame.
`
`In addition to OFDM, communication system 100
`[0032]
`utilizes Adaptive Modulation and Coding (AMC). With
`AMC, the modulation and coding format of a transmitted
`data stream for a particular receiver is changed to predomi—
`nantly match a current received signal quality (at
`the
`receiver) for the particular frame being transmitted. The
`modulation and coding scheme may change on a frame-by-
`frame basis in order to track the channel quality variations
`that occur in mobile communication systems. Thus, streams
`with high quality are typically assigned higher order modu-
`lations rates and/or higher channel coding rates with the
`modulation order and/or the code rate decreasing as quality
`decreases. For those receivers experiencing high quality,
`modulation schemes such as 16 QAM, 64 QAM or 256
`QAM are utilized, while for those experiencing low quality,
`modulation schemes such as BPSK or QPSK are utilized.
`
`[0033] Multiple coding rates may be available for each
`modulation scheme to provide finer AMC granularity,
`to
`enable a closer match between the quality and the transmit-
`
`PETITIONERS 1040-0022
`IPR2016-00758
`
`

`

`
`
`the term ‘slot’ may be used for ‘subframe’, or ‘transmission
`time interval (TTI)’ used for ‘frame’ or ‘frame duration’. In
`addition, a frame may be considered a user transmission
`specific quantity (such as a TTI associated with a user and
`a data flow), and frames therefore need not be synchronized
`or aligned between users or even transmissions from the
`same user (e.g., one subframe could contain parts of two
`data transmissions from a user, the first transmitted in a one
`subframe frame and the second transmitted in a four sub—
`frame frame). Of course, it may be advantageous to restrict
`either transmissions with a user or transmissions with mul-
`tiple users to have synchronized or aligned frames, such as
`when time is divided into a sequence of 0.5 ms or 2 ms
`frames and all resource allocations must be within these
`frames. As indicated above a radio frame can represent an
`aggregation of subframes or frames of different sizes or an
`aggregation of resources such as consecutive OFDM or
`DFT—SOFDM symbols exceeding the number of such sym-
`bols in a subframe where each symbol is composed of some
`munber of subcarriers depending on the carrier bandwidth.
`
`US 2007/0058595 A1
`
`Mar. 15, 2007
`
`R=1/z and R=2/: for 16 QAM, etc.). Note that AMC can be
`performed in the time dimension (e.g., updating the modu—
`lation/coding every Nt OFDM symbol periods) or in the
`frequency dimension (e.g., updating the modulation/coding
`every NSC subcarriers) or a combination of both.
`
`[0034] The selected modulation and coding may only
`predominantly match the current received signal quality for
`reasons such as channel quality measurement delay or errors
`or channel quality reporting delay. Such latency is typically
`caused by the rotmd-trip delay between a packet transmis-
`sion and an acknowledgment of the packet reception.
`
`In order to reduce latency, a Radio Frame (RAF)
`[0035]
`and subframe are defined such that the RAF is divided into
`a number (an integer number in the preferred embodiment)
`of subframes. Within a radio frame, frames are constructed
`from an integer number of subframes for data transmission,
`with two or more frame durations available (e.g., a first
`frame duration of one subframe, and a second frame dura—
`tion of three subframes).
`
`[0036] For example, a 10 ms core radio frame structure
`from UTKA may be defined, with NFF subframes per radio
`frame (e.g., Nrr=20 T§r=0.5 ms subframes, where Tsf=dura-
`tion of one subframe). For OFDM transmission, subframes
`comprise an integer number P of OFDM symbol intervals
`(e. g., P=1O for Tsn=5 us symbols, where Tsn=duration of one
`OFDM symbol), and one or more subframe types may be
`defined based on guard interval or cyclic prefix (e.g., nomial
`or broadcast).
`
`[0037] As one of ordinary skill in the art will recognize, a
`frame is associated with a scheduled data transmission. A
`frame may be defined as a resource that is ‘schedulable’, or
`a schedulable unit,
`in that
`it has an associated control
`structureipossibly uniquely associatedithat controls the
`usage of the resource (i.e. allocation to users etc.). For
`example, when a user is to be scheduled on a frame, a
`resource allocation message corresponding to a frame will
`provide resources (e.g., for an OFDM system a number of
`modulation symbols each of one subcarrier on one OFDM
`symbol) in the frame for transmission. Acknowledgements
`of data transmissions on a frame will be returned, and new
`data or a retransmission of data may be scheduled in a future
`frame. Because not all resources in a frame may be allocated
`in a resource allocation (such as in an OFDM system), the
`resource allocation may not span the entire available band-
`width ancL’or time resources in a frame.
`
`[0038] The different frame durations may be used to
`reduce latency and overhead based on the type of traffic
`served. For example, if a first transmission and a retrans—
`mission are required to reliably receive a voice over internet
`protocol (VoIP) data packet, and a retransmission can only
`occur after a one frame delay, allocating resources within a
`0.5 ms frame instead of a 2 ms frame reduces latency for
`reliable reception from 6 ms (transmission,
`idle frame,
`retransmission) to 1.5 ms. In another example, providing a
`resource allocation that will fit a user’s packet without
`fragmentation, such as a 1 ms frame instead of a 0.5 ms
`frame, can reduce overhead such as control and acknowl-
`edgement signaling for multiple fragments of a packet.
`
`aggregation of
`the
`reflecting
`names
`[0039] Other
`resources such as consecutive OFDM symbols may be used
`instead of subframe, frame, and radio frame. For example,
`
`[0040] The radio frame structure may additionally be used
`to define common control chalmels for downlink (DL)
`transmissions (such as broadcast channels, paging channels,
`synchronization channels, and/or indication channels) in a
`manner which is time—division multiplexed into the sub—
`frame sequence, which may simplify processing or increase
`battery life at the user equipment (remote unit). Similarly for
`uplink (UL) transmissions, the radio frame structure may
`additionally be used to define contention channels (e.g.
`random access chalmeliakACHD, control channels includ—
`ing pilot time multiplexed with the shared data channel.
`
`FIG. 2 is a block diagram of circuitry 200 for base
`[004]]
`station 104 or mobile station 101—103 to perform uplink and
`downlink transmission. As shown, circuitry 200 comprises
`logic circuitry 201,
`transmit circuitry 202, and receive
`circuitry 203. Logic circuitry 200 preferably comprises a
`microprocessor controller, such as, but not limited to a
`Freescale PowerPC microprocessor. Transmit and receive
`circuitry 202-203 are conunon circuitry known in the art for
`conmlunication utilizing a well known network protocols,
`and serve as means for transmitting and receiving messages.
`For example, transmitter 202 and receiver 203 are preferably
`well known transmitters and receivers that utilize a 3GPP
`network arotocol. Other possible transmitters and receivers
`include, jut are not limited to transceivers utilizing Blue-
`tooth, IA 4 4 802.16, or HyperLAN protocols.
`
`
`
`[0042] During operation, transmitter 203 and receiver 204
`transmi and receive frames of data and control information
`as discussed above. More particularly, data transmission
`takes place by receiving data to be transmitted over a radio
`frame. The radio frame (shown in FIG. 3) is comprised of a
`plurality of subframes 300 (only one labeled) wherein the
`duration of subframe 301 is substantially constant and the
`duration of the radio frame 300 is constant. For example
`only, a radio frame comprises m=20 subframes 300 of
`duration 0.5 ms consisting of j=10 symbols. During trans-
`mission, logic circuitry 201 selects a frame duration from
`two or more frame durations, where the frame duration is
`substantially the subframe duration multiplied by a number.
`Based on the frame duration, the number of subframes are
`grouped into the frame and data is placed within the sub-
`
`PETITIONERS 1040-0023
`IPR2016-00758
`
`

`

`
`
`[0044] There are two or more frame durations. If two
`frame durations are defined, they may be designated short
`and long, where the short frame duration comprises fewer
`subframes than the long frame duration. FIG. 4 shows a
`sequence of consecutive short frames 401 (short frame
`multiplex), and FIG. 5 shows a sequence of consecutive long
`frames 501 (long frame multiplex). Time may be divided
`in o a sequence of subframes, subframes grouped into
`frames of two or more durations, and frame duration may be
`di “erent between consecutive f