`
`ZTE Corporation and ZTE (USA) Inc.
`
`
`
`Inv. No. 337-TA-868
`
`RX-3053
`
`3GPP TSG-RAN WG1#25
`Paris, France
`9 — 12 February, 2002
`
`Agenda Item :
`
`6
`
`Source :
`
`Siemens
`
`Tdoc R1-02-0400
`
`Title :
`
`UE Specific Bit Scrambling for TDD HS—SCCH
`
`Document for:
`
`Discussion and Decision
`
`1. Introduction
`
`In TDD I-ISDI’A, the UE must continuously monitor up to 4 I-IS-SCCI-ls, but at most onc of these may be addresscd to
`the UP, in any given TTI. Currently, however, the UE cannot tell if a HS-SCCH is addressed to it until it has computed
`the UE Id contained implicitly in the CRC, which means that the HE must decode a HS—SCCH completely before it can
`be rejected. This places particular constraints on the HS-SCCH processing time requirements in the UE. It would be
`useful if a method of rejecting a HS-SCCH earlier was available to the UE. Providing such a mechanism would also
`reduce the probability that a UE will incorrectly accept an HS—SCCH transmission as being intended for it when it was
`not.
`
`2. UE Specific Bit Scrambling for the TDD HS-SCCH
`In FDD, a UE specific masking sequence is used over Pait l of the HS-SCCH for this purpose, and a similar approach
`can be used in TDD by making use of the bit scrambling operation already defined in [1]. The bit scrambling sequence
`would be made UE specific for the TDD HS—SCCH and applied at the output of the rate matching operation. The
`modified coding and multiplexing chain for the TDD HS—SCCH would be as shown in Figure 1 below.
`
`The bit scrambling operation in [I] can be made UE specific by initialising the shift register values to be equal to the
`UE Id itself. 111 addition, the requirement that [11 = l is removed, and instead this bit is allowed to take its natural value
`as a result of the modulo 2 addition operation. The bit scrambling scqucncc {pk : k = LR} . where R is 172 for 1.28
`Mcps TDD and 244 for 3.84 Mcps TDD, can thus be generated as follows ,
`16
`
`pk=[Zgilpkrijm0d2
`
`l:l
`
`k=1"R
`
`whcrc
`
`gi=0sg2 =0~g3=0~g4=0~g5 =0~g6 =0’g7=0‘g8=0’g9 =0~g10=0~gii=1~g12 =O~gis =l’g14=1’g15 =0~gia =1
`
`pk =0
`
`k=0..75
`
`pk :xuevisik
`
`k : —6..—15
`
`and {x
`
`142,1?
`
`ue,2 >"
`
`x
`
`., x“, 10} is the UE Id.
`
`If the CE attempts to decode a HS—SCCH that is not intended for it, then it will be using the wrong bit scrambling
`sequence to unscramble it. This should be apparent to the UE from the decision metrics in the convolutional decoder,
`and it can choose to abort the operation early. Alternatively, it can decode the IIS-SCCII in full, with only a small
`probability that the CRC will check out correctly for the UP. specific scrambling code being used.
`
`NK868ITCO’130891 15
`
`ZTE Corporation and ZTE (USA) Inc.
`Exhibit 1036-00001
`
`
`
`xndd
`xtbs,l"xfbs,m xhap,l"xhap,3 xrv,1"xrv,3
`xms,l
`xtx,l"xt.v,n
`xccs,1”xcm,8
`
`l
`l
`l
`l
`l
`l
`
`Multip exing
`
`
`a1,a2...aA '
`CRC attachment
`
`b1,b2...b3 V
`Channe Coding
`
`01,02...CC V
`
`Rate Matching
`
`fiafszR
`
`Bit Scrambling
`
` V s
`
`1,s2...sR V
`
`Interleavi ng
`
` V
`
`
`v1,v2...vR V
`Physical Channel
`
`Segmentation
`
`V
`uppupzuitpUp V
`Physical Channel
`Mapping
`
`PhC-l#n
`
`V
`
`PhCH#‘l
`
`Figure 1 : Modified TDD HS-SCCH Coding and Multiplexing Chain
`
`For 1.28 Mcps TDD, a histogram of the cross-correlation scores for the 1024 members of the bit scrambling sequence
`set are shown in Figure 2 below. It can be seen that there is a maximum cross-correlation within the set of about 25 %.
`Hence it is unlikely that channel errors will allow a UE to confuse another bit scrambling sequence with its own. Even
`were this to happen, the UE specific CRC should still normally indicate that the message is not addressed to the UE.
`
`NK868ITC013089116
`
`ZTE Corporation and ZTE (USA) Inc.
`Exhibit 1036-00002
`
`
`
`
`
`
`0.20
`
`
`
`0.12
`
`0.04
`
`
`
`
`
`
`
`
`Probability 0.08
`
`0.00
`
`Co rre lation Sco re
`
`Figure 2 : Histogram of Cross Correlation Scores for 1.28 Mcps HS-SCCH Masking Code Set
`
`3. Conclusions
`
`It is proposed that a UE specific bit scrambling sequence be used for the TDD HS-SCCH. This will allow a UE to reject
`HS-SCCH transmissions not addressed to it earlier than is currently the case. The UE specific bit scrambling sequence
`can be generated using a slightly modified form of the existing bit scrambling code generator.
`
`4. References
`
`[1].
`
`3GPP TS 25.222, “Multiplexing and channel coding (TDD)”
`
`5. Modified Text Proposal for TR 25.858
`
`- -’ - - - - Start of Text Proposal Part 1, TR 25.858 V5.0.0 Section 8.1.3.1 - -‘- ‘- '- - -
`
`8.1.3.1
`
`HS-SCCH Coding
`
`8.1.3.4.1
`
`1.28 Mcps TDD
`
`The information fields of the HS-SCCH are multiplexed together to form a single 43 bit field, which is then encoded
`using the R99 1/3-rate convolutional coder, which yields an encoded block size of 153 bits. The encoded block is
`mapped to two bursts, one using Slot Format 0, which has a payload of 88 bits, and the other using Slot Format 5, which
`has a payload of 84 bits, plus TPC and SS bits for the HS-SICH. The R99 rate-matching algorithm is used to adapt the
`
`encoded block size to the actual slot payload. After rate matching the data is scrambled using a UE specific bit
`
`scrambling sequence. This sequence is generated using the TDD bit scrambling generator but with the state of the shift
`
`register initialised to be equal to the UE ld.
`
`The coding and multiplexing process for the 1.28 Mcps TDD HS-SCCH is shown below.
`
`NK868ITC013089117
`
`ZTE Corporation and ZTE (USA) Inc.
`Exhibit 1036-00003
`
`
`
`
`
`
`
`
`
`(zinFliltls)
`(3.12:3
`(illiEblis)
`
`TFRI
`HARQ /UE Id/CRC
`
`
`(20 bits)
`(7 bits)
`(16 bits)
`
`
`
`
`
`43 bits
`8
`
`
`
`Conv. Coding 1/3 Rate
`(43 + 8) X 3 = 153 bits
`
`
`
`172 bits
`
`
`
`HS'SCCH Data
`
`Field Coding and
`Multiplexing
`
`Tail Bit Attachment
`
`Rate Matching
`
`2nd Interleaving
`
`Slot Formatting
`(2 X SF=15)
`
`HS'SCCH Data
`
`Field Coding and
`Multiplexing
`
`Tail Bit Attachment
`
`Conv. Coding 1/3 Rate
`
`Rate Matching
`
`UE Specific Bit
`Scrambling
`
`2nd Interleaving
`
`Slot Formatting
`(2 X SF=16)
`
`
`
`172 bits / 5 ms
`
`Field 1
`Midamble
`SS
`TPC
`Field 2
`
`
`
`
`
`(44 bits)
`(144 chips)
`(2 bits)
`(2 bits)
`(40 bits)
`Field 1
`Midamble
`Field 2
`(44 bits)
`(144 chips)
`(44 bits)
`
`
`
`
`
`
`
`
`(zlJFiills)
`(ii/fill?)
`(lilEbilis)
`
`
`HARQ iUE ld/cRc
`TFRI
`
`(20 bits)
`(7 bits)
`(16 bits)
`
`
`43 bits
`8
`
`
`
`(43 + 8) X 3 = 153 bits
`
`
`
`172 bits
`
`
`
`172 bits
`
`
`
`172 bits / 5 ms
`
`Field 1
`Midamble
`SS
`TPC
`Field 2
`
`
`
`
`
`
`(44 bits)
`(144 chips)
`(2 bits)
`(2 bits)
`(40 bits)
`Field 1
`Midamble
`Field 2
`(44 bits)
`(144 chips)
`(44 bits)
`
`Figure 1. Coding and Multiplexing Scheme for HS-SCCH
`
`8.13.4.2
`
`3.84 Mcps TDD
`
`Burst Type 1, which has a data payload of 244 bits is used for HS-SCCH. The TFRI, HARQ information and CRC /
`UE-ID are combined into a single 53 bit field. The Release 99 rate 1/3 convolutional encoder expands this field to 183
`bits. Rate matching matches these 183 bits to the 244 bits available in burst type 1. After interleaving the data is
`scrambled using a UE specific bit scrambling sequence. This sequence is generated using the TDD bit scrambling
`
`generator but with the state of the shift register initialised to be equal to the UE Id. The coding and multiplexing
`process for HS-SCCH is given in the figure below:
`
`NK868ITCO13089118
`
`ZTE Corporation and ZTE (USA) Inc.
`Exhibit 1036-00004
`
`
`
`
`
`
`UE—ID (10 bits)
`TFRI (31 bits)
`HARQ (6 bits)
`
`
`
`
`
`
`
`HARQ (6 bits)TFRI (31 bits) CRC /UE—]D (16 bits)
`
`
`
`
`
`53 bits
`
`
`(53+8)x3 : 183 bits
`
`
`244 bits
`
`244 bis
`
`
`
`
`244 bits
`
`
`midamble (512
`Field 1 (122 bits)
`Field 2 (122 bits)
`
`ch'ps)
`
`
`
`
`
`
`TFRI (31 bits)
`HARQ (5 m5)
`UE-ID (10 bits)
`
`
`
`
`
`
`HARQ (6 bits)
`CRC / UE-lD (16 bits)
`TERI (31 bitS)
`
`
`
`'l'a1l bit attachment
`53 bits
`8
`
`
`Conv. Codmg l 3 Rate
`
`(53 + 8) x3 : 183 bits
`
`244 bits
`
`
`
`
`
`
`
`
`244 bits
`
`
`
`
`HS—SCCH data
`
`Field coding and
`multiplexing
`
`Tail bit attachment
`
`Conv. Coding 1/3 Rate
`
`Rate matching
`
`UE Specific Bit Scrambling
`
`2n01 Interleaving
`
`Burst formatting
`
`HS-SCCH data
`
`Field coding and
`multiplexing
`
`Rate matching
`
`2"“1 Interleaving
`
`Burst formatting
`
`guard (95
`
`chins)
`Fieldl (122 bits)
`“MESS”
`Field 2 (122 bits)
`
`
`
`
`
`
`
`
`
`Egg—eflqudjllgAnsi MUJtiplezdpg Schemg for £284 MSQSES—SCCH ,,,,,,,,,,,,,, 2 , , i Formatted
`
`------ End afText Proposal Part 1, TR 25.858 V5. 0.0 Section 8.1.3.1- - - - _,_ -
`
`NK868ITCO13089119
`
`ZTE Corporation and ZTE (USA) Inc.
`Exhibit 1036-00005
`
`