5.1a.19 Packet data block type 30 (DAS-8)

3GPP45.003GSM/EDGE Channel codingRelease 17TS

5.1a.19.1 Block constitution

If the message delivered to the encoder does not include a PAN, it has a fixed size of 941 information bits {d(0),d(1),…,d(940)}. If the message delivered to the encoder does not include a PAN but includes an eTFI, it has a fixed size of 944 information bits {d(0),d(1),…,d(943). If the message delivered to the encoder includes a PAN but does not include an eTFI, it has a fixed size of 966 information bits {d(0),d(1),…,d(965). If the message delivered to the encoder includes a PAN and an eTFI, it has a fixed size of 969 information bits {d(0),d(1),…,d(968).

NOTE: The presence of the PAN is indicated by the PANI field in the header (see 3GPP TS 44.060).

The message is separated into the following parts:

u(k) = d(k) for k = 0,…,2

h(k-3) = d(k) for k = 3,…,40

i1(k-41) = d(k) for k = 41,…,490

i2(k-491) = d(k) for k = 491,…,940

And if an eTFI is included:

et(k-941) = d(k) for k = 941,…,943

And if a PAN is included:

pn(k-941) = d(k) for k = 941,…,965

And if a PAN and an eTFI are included:

et(k-966) = d(k) for k = 966,…,968

5.1a.19.2 USF coding

5.1a.19.2.1 BTTI configuration

The USF bits {u(0),u(1),u(2)} are block coded into 48 bits u’(0),u’(1),…,u’(47) according to the following table:

u(0),u(1),u(2)	u’(0),u’(1),…,u’(47)
	burst 0	burst 1	burst 2	burst 3
000	0 1 1 1 1 1 1 1 1 1 1 1	1 1 1 1 1 1 1 1 1 0 1 1	0 0 1 1 0 1 1 1 0 1 1 1	1 1 1 1 1 0 1 1 1 0 1 1
001	0 0 1 1 0 0 1 1 0 1 1 1	0 0 1 1 0 1 1 1 0 1 1 1	0 0 1 1 0 0 1 1 0 1 1 1	0 0 1 1 0 0 1 1 0 1 1 1
010	0 1 1 1 0 1 1 1 1 1 1 1	0 0 1 1 0 0 1 1 0 1 1 1	1 1 1 1 1 1 1 1 1 0 1 1	0 0 1 1 0 1 1 1 1 1 1 1
011	1 1 1 1 1 0 1 1 0 0 1 1	1 0 1 1 0 0 1 1 0 0 1 1	0 1 1 1 0 1 1 1 1 1 1 1	1 0 1 1 1 0 1 1 0 0 1 1
100	0 0 1 1 0 1 1 1 0 1 1 1	0 1 1 1 1 1 1 1 1 1 1 1	1 0 1 1 1 0 1 1 0 0 1 1	1 1 1 1 1 1 1 1 1 0 1 1
101	1 0 1 1 0 0 1 1 0 0 1 1	1 0 1 1 1 0 1 1 1 0 1 1	0 1 1 1 1 1 1 1 1 1 1 1	0 1 1 1 1 1 1 1 1 1 1 1
110	1 1 1 1 1 1 1 1 1 0 1 1	1 1 1 1 1 0 1 1 0 0 1 1	1 0 1 1 0 0 1 1 0 0 1 1	0 1 1 1 0 1 1 1 0 1 1 1
111	1 0 1 1 1 0 1 1 1 0 1 1	0 1 1 1 0 1 1 1 1 1 1 1	1 1 1 1 1 0 1 1 1 0 1 1	1 0 1 1 0 0 1 1 0 0 1 1

5.1a.19.2.2 RTTI configurations

If the USF is sent in RTTI USF mode (see 3GPP TS 45.002) when data blocks are transmitted in RTTI configuration, then the USF bits {u(0),u(1),u(2)} are block coded into 48 bits u’(0),u’(1),…,u’(47) as described in subclause 5.1a.19.2.1.

If the USF is sent in BTTI USF mode (see 3GPP TS 45.002) when data blocks are transmitted in RTTI configuration, then the three bits of the USF to be sent on the lower numbered PDCH of a corresponding downlink PDCH-pair are block coded into 48 bits u_L(0),u_L(1),…,u_L(47) as described in subclause 5.1a.19.2.1; the three bits of the USF to be sent on the higher numbered PDCH of a corresponding downlink PDCH-pair are block coded into 48 bits u_H(0),u_H(1),…,u_H(47) as described in subclause 5.1a.19.2.1.

NOTE: If BTTI USF mode is used when sending data blocks in RTTI configuration, then u(0),u(1),u(2) need not contain a USF; in this case, they are ignored by the encoder. How the USFs are delivered to the encoder in this case is implementation dependent.

If the data block is sent in the first 10ms of a 20ms block period, then:

u’(j)=u_L(j), j=0…11

u’(j)=u_H(j-12), j=12…23

u’(j)=u_L(j-12), j=24…35

u’(j)=u_H(j-24) j=36…47

If the data block is sent in the second 10ms of a 20ms block period, then:

u’(j)=u_L(j+24), j=0…11

u’(j)=u_H(j+12), j=12…23

u’(j)=u_L(j+12), j=24…35

u’(j)=u_H(j) j=36…47

NOTE: In case mixed modulation USF is used (see subclause 5.1), the USF bits sent during the other half of the 20 ms block period may be sent with a different modulation. In this case, the half of u_L and u_H not sent in the present data block will be discarded.

5.1a.19.3 Header coding

The header {h(0),…,h(37)} is coded as defined in subclause 5.1a.1.1, with N=38, resulting in a block of 138 bits, {C(0),…,C(137)}.

The code is punctured in such a way that the following coded bits:

{C(k) for k = 8 and 77} are not transmitted

This results in a block of 136 bits, {hc(0),…,hc(135)}.

5.1a.19.4 Data coding

Each data part, {i1(0),…,i1(449)} and {i2(0),…,i2(449)}, is coded as defined in subclause 5.1a.1.3, with N=450, resulting in two coded blocks of 1398 bits, {C1(0),…,C1(1397)} and {C2(0),…,C2(1397)}.

Each coded block is punctured depending on the value of the CPS field as defined in 3GPP TS 44.060. Two puncturing schemes named P1 or P2 are applied.

The parameter values used for rate matching are: swap=0, =466,=832 and =793.

P1 puncturing is generated according to 5.1a.1.3.5

P2 (Type 1) puncturing is generated according to 5.1a.1.3.5.

If a PAN is not included, the result is two blocks of 832 bits, {c1(0),…,c1(831)} and {c2(0),…,c2(831)}.

If a PAN is included, the result is two blocks of 793 bits, {c1(0),…,c1(792)} and {c2(0),…,c2(792)}.

NOTE: C1 and c1 correspond to i1, and C2 and c2 to i2.

5.1a.19.5 PAN coding

The PAN coding is the same as for UAS-7 as specified in subclause 5.1a.3.4.

5.1a.19.6 Interleaving

a) Header

The header, {hc(0),…,hc(135)}, is interleaved as defined in subclause 5.1a.2.1, with N_C=136 and a=23, resulting in a block of 136 bits, {hi(0),…,hi(135)}.

b) Data and PAN

If a PAN is not included, data are put together as one entity as described by the following rule:

dc(k) = c1(k) for k = 0,…,831

dc(k) = c2(k-832) for k = 832,…,1663

If a PAN is included, data and PAN are put together as one entity as described by the following rule:

dc(k) = ac(k) for k = 0,…,77

dc(k) = c1(k-78) for k = 78,…,870

dc(k) = c2(k-871) for k = 871,..,.1663

The block {dc(0),…,dc(1663)} is interleaved as defined in subclause 5.1a.2.1, with N_C=1664 and a=199, resulting in a block of 1664 bits, {di(0),…,di(1663)}.

5.1a.19.7 Mapping on a burst

a) Straightforward mapping

The mapping is given by the rule:

For B=0,1,2,3, let

e(B,j) = di(416B+j) for j = 0,…,207

e(B,j) = hi(34B+j-208) for j = 208,…,227

e(B,j) = q(2B+j-228) for j = 228,229

e(B,j) = hi(34B+j-210) for j = 230,…,231

e(B,j) = u’(12B+j-232) for j = 232,…,243

e(B,j) = hi(34B+j-222) for j = 244,…,255

e(B,j) = di(416B+j-48) for j = 256,…,463

where

q(0),q(1),…,q(7) = 0,0,0,0,0,0,0,0 identifies the coding scheme DAS-8 or DAS-9.

b) Bit swapping

After this mapping the following bits are swapped:

For B = 0,1,2,3,

Swap e(B,184+k) with e(B,210+k) for k=0, 1, 4, 5, 8, 9, 12, 13, 16, 17, 20, 21.

Swap e(B,256+k) with e(B,246+k) for k=0, 1, 4, 5, 8, 9.

In RTTI configuration, the bursts with B = 0,2 shall be mapped on the PDCH having the lower timeslot number, whereas the bursts with B = 1,3 shall be mapped on the PDCH having the higher timeslot number, see 3GPP TS 45.002.

c) PAN bit swapping

In case a PAN is included in the radio block, the following additional bits are swapped after the bit swapping in b):

For B = 0

Swap e(B,55) with e(B,40)

Swap e(B,91) with e(B,81)

Swap e(B,127) with e(B,120)

Swap e(B,163) with e(B,160)

Swap e(B,199) with e(B,177)

Swap e(B,302) with e(B,268)

Swap e(B,338) with e(B,305)

Swap e(B,374) with e(B,368)

Swap e(B,410) with e(B,405)

Swap e(B,446) with e(B,444)

For B = 1

Swap e(B,23) with e(B,120)

Swap e(B,59) with e(B,160)

Swap e(B,95) with e(B,177)

Swap e(B,150) with e(B,12)

Swap e(B,186) with e(B,81)

Swap e(B,230) with e(B,181)

Swap e(B,415) with e(B,268)

Swap e(B,451) with e(B,305)

Swap e(B,270) with e(B,368)

Swap e(B,306) with e(B,405)

Swap e(B,342) with e(B,444)

For B = 2

Swap e(B,46) with e(B,40)

Swap e(B,82) with e(B,81)

Swap e(B,118) with e(B,120)

Swap e(B,154) with e(B,160)

Swap e(B,190) with e(B,177)

Swap e(B,311) with e(B,268)

Swap e(B,347) with e(B,305)

Swap e(B,383) with e(B,368)

Swap e(B,419) with e(B,405)

Swap e(B,455) with e(B,444)

For B = 3

Swap e(B,14) with e(B,120)

Swap e(B,50) with e(B,160)

Swap e(B,86) with e(B,180)

Swap e(B,159) with e(B,40)

Swap e(B,195) with e(B,81)

Swap e(B,406) with e(B,268)

Swap e(B,442) with e(B,305)

Swap e(B,279) with e(B,368)

Swap e(B,315) with e(B,405)

Swap e(B,351) with e(B,444)