5.1a.18 Packet data block type 29 (DAS-7)

3GPP45.003GSM/EDGE Channel codingRelease 17TS

5.1a.18.1 Block constitution

If the message delivered to the encoder does not include a PAN, it has a fixed size of 686 information bits {d(0),d(1),…,d(685)}. If the message delivered to the encoder does not include a PAN but includes an eTFI, it has a fixed size of 689 information bits {d(0),d(1),…,d(688). If the message delivered to the encoder includes a PAN but does not include an eTFI, it has a fixed size of 711 information bits {d(0),d(1),…,d(710). If the message delivered to the encoder includes a PAN and an eTFI, it has a fixed size of 714 information bits {d(0),d(1),…,d(713).

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

5.1a.18.2 USF coding

A block of 36 bits {u’(0),u’(1),…,u’(35)} is derived as described for MCS-5 DL in subclause 5.1.9.1.2.

5.1a.18.3 Header coding

A block of 100 coded bits {hc(0),hc(1),…,hc(99)} is derived from {d(3),d(4),…,d(27)} as described for MCS-5 DL in subclause 5.1.9.1.3.

In case an eTFI field is included and a PAN field is not included the three bits {d(686),d(687),d(688)} are added bit-wise modulo 2 to the last three parity bits {p(5), p(6),p(7)} as specified in clause 5.1.9.1.3. In case an eTFI field and a PAN field are included the three bits {d(711),d(712),d(713)} are added bit-wise modulo 2 to the last three parity bits {p(5), p(6),p(7)} as specified in clause 5.1.9.1.3.

5.1a.18.4 Data coding

The data, defined as

i(k) = d(k+28) for k = 0,…,657

is coded as defined in subclause 5.1a.1.3, with N=658, resulting in a coded block of 2022 bits, {C(0),…,C(2021)}.

The 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, =674,=1248 and =1172.

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 a block of 1248 bits, {c(0),…,c(1247)}.

If a PAN is included, the result is a block of 1172 bits, {c(0),…,c(1171)}.

5.1a.18.5 PAN coding

The PAN, if included, is defined as

pn(i) = d(686+i) for i=0,…,24.

The PAN coding is the same as for MCS-5 DL as specified in subclause 5.1.9.1.4a.

5.1a.18.6 Interleaving

The interleaving is the same as for DAS-5 as specified in subclause 5.1a.16.6.

5.1a.18.7 Mapping on a burst

The mapping is the same as for MCS-5 DL as specified in subclause 5.1.9.1.6.

NOTE: In this case, the stealing flags q(0),q(1),…,q(7) = 0,0,0,0,0,0,0,0 identify the coding scheme DAS-5, DAS-6 or DAS-7.