7 Mapping of transport channels to physical channels for the 1.28 Mcps option
25.2213GPPPhysical channels and mapping of transport channels onto physical channels (TDD)Release 17TS
This clause describes the way in which the transport channels are mapped onto physical resources, see figure 22.
Transport channels |
Physical channels |
DCH |
Dedicated Physical Channel (DPCH) |
BCH |
Primary Common Control Physical Channels (P-CCPCH) |
PCH |
Secondary Common Control Physical Channels(S-CCPCH) |
FACH |
Secondary Common Control Physical Channels(S-CCPCH) |
PICH |
|
MICH |
|
PLCCH |
|
RACH |
Physical Random Access Channel (PRACH) |
USCH |
Physical Uplink Shared Channel (PUSCH) |
DSCH |
Physical Downlink Shared Channel (PDSCH) |
Down link Pilot Channel (DwPCH) |
|
Up link Pilot Channel (UpPCH) |
|
FPACH |
|
HS-DSCH |
High Speed Physical Downlink Shared Channel (HS-PDSCH) |
Shared Control Channel for HS-DSCH (HS-SCCH) |
|
Shared Information Channel for HS-DSCH (HS-SICH) |
|
E-DCH |
E-DCH Physical Uplink Channel (E-PUCH) |
E-DCH Uplink Control Physical Channel (E-UCCH) |
|
E-DCH Random Access Uplink Control Channel (E-RUCCH) |
|
E-DCH Absolute Grant Channel (E-AGCH) |
|
E-DCH Hybrid ARQ Indicator Channel (E-HICH) |
Figure 22: Transport channel to physical channel mapping for 1.28Mcps TDD
7.1 Dedicated Transport Channels
7.1.1 The Dedicated Channel (DCH)
The mapping of transport blocks to physical bearers is in principle the same as in 3.84 Mcps TDD but due to the subframe structure the coded bits are mapped onto each of the subframes within the given TTI.
Figure 23 : Mapping of Transport Blocks onto the physical bearer ( TTI= 20ms )
7.1.2 The Enhanced Uplink Dedicated Channel (E-DCH)
The enhanced uplink dedicated channel is mapped on one or several E-PUCH, see subclause 5A.3.14.
For multi-carrier E-DCH transmission, the E-DCH on one carrier is always associated with a number of E-AGCH and up to four E-HICHs on the same carrier. The E-DCH, E-AGCH and E-HICH on the same carrier obey the following timing relationships.
7.1.2.1 E-DCH/E-AGCH Association and Timing
The E-DCH is always associated with a number of E-DCH Absolute Grant Channels (E-AGCH) and up to four hybrid ARQ Indicator Channel (E-HICH). A grant of E-DCH transmission resources may be transmitted to the UE on any one of the associated E-AGCH. All relevant Layer 1 control information related to an E-DCH TTI is transmitted in the associated E-AGCH and E-HICH.
The E-DCH related timeslot information that is carried on the E-AGCH refers to the next valid E-PUCH allocation, which is given by the following limitation: There shall be an offset of nE-AGCH 7 time slots between the E-AGCH carrying the E-DCH related information and the first indicated E-PUCH (in time) for a given UE. DwPTS and UpPTS shall not be taken into account in this limitation as illustrated in figure 23A. Note that the figure only shows the E-AGCH that carries the E-DCH related information for the given UE and that DwPTS and UpPTS are not considered in this figure.
Figure 23A: Timing for E-AGCH and E-PUCH for different radio frame configurations for a given UE
When E-AGCH is allocated in TS0, the timing between E-AGCH and the associated E-PUCH is defined as: E-AGCH is sent in the n-th sub-frame while the E-PUCH is sent in the (n+2)-th sub-frame.
For the semi-persistent E-DCH resources, the timing between E-AGCH and the first E-PUCH can also use the same limitation: There shall be an offset of nE-AGCH 7 time slots between the E-AGCH carrying the semi-persistent E-DCH related information and the first indicated semi-persistent E-PUCH (in time) for a given UE. Once the semi-persistent resources are assigned to UE, UE can use these resources continuously until the semi-persistent resources have been released or reconfigured by Node B or RNC.
7.1.2.2 E-DCH/E-HICH Association and Timing
For a given UE, a HARQ acknowledgement indicator (E-HICH) is synchronously linked with the E-DCH TTI transmission to which it relates.
The associated E-HICH shall reside on the first E-HICH instance of the E-HICH channelisation code to occur after nE-HICH timeslots have elapsed since the start of the last E-PUCH of the corresponding E-DCH TTI (see examples of figure 23B). DwPTS and UpPTS are not considered in the figure. The value of nE-HICH is configurable by higher layers within the range 4 to 15 timeslots. DwPTS and UpPTS shall not be taken into account in this limitation.
Figure 23B: Timing for E-DCH and E-HICH for a given UE
7.2 Common Transport Channels
7.2.1 The Broadcast Channel (BCH)
There are two P-CCPCHs, P-CCPCH 1 and P-CCPCH 2 which are mapped onto timeslot#0 using the channelisation codes and
with spreading factor 16. The BCH is mapped onto the P-CCPCH1+P-CCPCH2.
The position of the P-CCPCHs is indicated by the relative phases of the bursts in the DwPTS with respect to the P-CCPCHs midamble sequences, see [8]. One special combination of the phase differences of the burst in the DwPTS with respect to the P-CCPCH midamble indicates the position of the P-CCPCH in the multi-frame and the start position of the interleaving period.
7.2.2 The Paging Channel (PCH)
If the PICH is associated with an S-CCPCH to which a PCH transport channel is mapped, the mapping of Paging Channels onto S-CCPCHs and the association between PCHs and Paging Indicator Channels is the same as in the 3.84 Mcps TDD option, cf. 6.2.2 ‘The paging Channel’ and 6.2.2.1 ‘PCH/PICH Association’ respectively.
7.2.3 The Forward Channel (FACH)
The FACH is mapped onto one or several S-CCPCHs. The location of the FACH is indicated on the BCH and both, capacity and location can be changed, if required. FACH may or may not be power controlled.
7.2.4 The Random Access Channel (RACH)
The RACH is mapped onto PRACH. More than one slot per frame may be administered for the PRACH. The location of slots allocated to PRACH is broadcast on the BCH. The uplink sync codes (SYNC-UL sequences) used by the UEs for UL synchronisation have a well known association with the P-RACHs, as broadcast on the BCH. On the PRACH, both power control and uplink synchronisation control are used.
7.2.5 The Uplink Shared Channel (USCH)
The uplink shared channel is mapped onto one or several PUSCH, see subclause 5A.3.6 ‘Physical Uplink Shared Channel (PUSCH)’
7.2.6 The Downlink Shared Channel (DSCH)
The downlink shared channel is mapped onto one or several PDSCH, see subclause 5A.3.7 ‘Physical Downlink Shared Channel (PDSCH)’
7.2.7 The High Speed Downlink Shared Channel (HS-DSCH)
The high speed downlink shared channel is mapped on one or several HS-PDSCH, see subclause 5A.3.9.
7.2.7.1 HS-DSCH/HS-SCCH Association and Timing
The HS-DSCH can be associated with a number of High Speed Shared Control Channels (HS-SCCH). In a multi-frequency HS-DSCH cell, HS-DSCH may be mapped on HS-PDSCHs on one or more carrier in CELL_DCH state and on only one carrier in CELL_FACH, CELL_PCH and URA_PCH state for UE supporting multi-carrier HS-DSCH reception configured by higher layers. HS-DSCH transmission on each carrier is associated with a HS-SCCH subset and the number of HS-SCCHs in one HS-SCCH subset can range from a minimum of one HS-SCCH (M=1) to a maximum of four HS-SCCH (M=4). All the HS-SCCH subsets for one UE constitute a HS-SCCH set. For UE not supporting multi-carrier HS-DSCH reception, only one HS-SCCH subset is allocated by higher layers. All relevant Layer 1 control information is transmitted in the associated HS-SCCH i.e. the HS-PDSCH does not carry any Layer 1 control information.
The HS-DSCH related time slot information that is carried on the HS-SCCH refers to the next valid HS-PDSCH allocation, which is given by the following limitation: The indicated HS-PDSCH shall be on the sub-frame next to the HS-SCCH carrying the HS-DSCH related information. The HS-DSCH related time slot information shall not refer to two subsequent sub-frames but shall always refer to the following sub-frame, as illustrated in figure 24. Note that the figure only shows the HS-SCCH that carries the HS-DSCH related information for the given UE and that DwPTS and UpPTS are not considered in this figure. In case of multi-carrier HS-DSCH reception, the timing for HS-DSCH transmission on each carrier and its associated HS-SCCH applies the same rule.
When the indicated HS-PDSCH includes TS0, the timing between HS-SCCH and HS-PDSCH including TS0 is defined as: HS-SCCH is sent in the n-th sub-frame while HS-PDSCH is sent in the (n+1)-th sub-frame, where the included TS0 is sent in TS0 of the (n+2)-th sub-frame.
For the semi-persistent HS-DSCH resources, the timing between HS-SCCH and the first HS-PDSCH applies the rule that, if the HS-SCCH is transmitted in subframe N, then the first HS-PDSCH is transmitted in subframe N+2, as illustrated in figure 24A. Once the semi-persistent resources are assigned to UE, UE can use these resources continuously until the semi-persistent resources have been released or reconfigured by Node B or RNC.
Figure 24: Timing for HS-SCCH and HS-DSCH for different radio frame configurations for a given UE
Figure 24A: Timing for HS-SCCH and first semi-persistent HS-DSCH for different radio frame configurations for a given UE
7.2.7.2 HS-SCCH/HS-DSCH/HS-SICH Association and Timing
The HS-SCCH is always associated with one HS-SICH, carrying the ACK/NACK and Channel Quality information (CQI). The association between the HS-SCCH in DL and HS-SICH in UL shall be pre-defined by higher layers and is common for all UEs. For the HS-DSCH semi-persistent scheduling operation, the associated HS-SICH to the HS-DSCH is conveyed by HS-SICH Indicator on HS-SCCH.
The UE in CELL_DCH state and in CELL_FACH state with a dedicated UE identity shall transmit the HS-DSCH related ACK / NACK on the next available associated HS-SICH with the following limitation: There shall be an offset of nHS-SICH 9 time slots between the last allocated HS-PDSCH (in time) and the HS-SICH for the given UE. DwPTS and UpPTS shall not be taken into account in this limitation. Hence, the HS-SICH transmission shall always be made in the next but one sub-frame, following the HS-DSCH transmission, as illustrated in figure 25. Note that the figure only shows the HS-SICH that carries the HS-DSCH related ACK / NACK for the given UE and that DwPTS and UpPTS are not considered in this figure. In case of multi-carrier HS-DSCH reception, the timing for HS-DSCH transmission on each carrier and its related HS-SICH applies the same rule. For the HS-SCCH order which is an uplink synchronization establishment order for UEs in CELL_FACH and CELL_PCH state, the UE shall not transmit associated HS-SICH.
Figure 25: Timing for HS-DSCH and HS-SICH for different radio frame configurations for a given UE
When the indicated HS-PDSCH includes TS0, the timing between HS-PDSCH including TS0 and HS-SICH is defined as: HS-PDSCH is sent in the n-th sub-frame while HS-SICH is sent in the (n+2)-th sub-frame, where the included TS0 is sent in TS0 of the (n+1)-th sub-frame and there shall be an offset of nHS-SICH 9 time slots between the last allocated HS-PDSCH (in time) and the HS-SICH.
There shall be an associated HS-SICH for the HS-SCCH command for allocation or release of the semi-persistent HS-PDSCH resources and HS-SCCH command for activation or deactivation of DRX. There shall also be an associated HS-SICH for HS-SCCH type1 or HS-SCCH type 4 or HS-SCCH type 8 with transport block size information set to all zeros. There is no associated HS-PDSCH in these cases. The timing between the HS-SCCH and the HS-SICH for the given UE as illustrated in figure 25A. The UE shall transmit the HS-SCCH related ACK on the next available associated HS-SICH with the following limitation: There shall be an offset of n’HS-SICH 14 time slots between the HS-SCCH (in time) and the HS-SICH for the given UE. DwPTS and UpPTS shall not be taken into account in this limitation.
Figure 25A: Timing for HS-SCCH and HS-SICH for different radio frame configurations for a given UE
When HS-SCCH is allocated in TS0, the timing between HS-SCCH for the HS-SCCH command and the associated HS-SICH is defined as: HS-SCCH is sent in the n-th sub-frame while HS-SICH is sent in the (n+3)-th sub-frame.
7.2.7.3 PICH/HS-SCCH/HS-DSCH Association and Timing
When the UE in CELL_PCH state with a dedicated UE identity detects the PICH identifying DCCH/DTCH/BCCH transmission, the UE shall receive the corresponding HS-SCCH subframes. The association and timing between PICH and HS-SCCH is depicted in figure 25A. If a paging indicator in a certain PICH block is set to ‘1’ it is an indication that UEs associated with this paging indicator shall read their corresponding HS-SCCH in the M frames where M is Reception window size configured by higher layers. The value NGAP>0 of frames between the end of the PICH block and the beginning of the HS-SCCH is configured by higher layers. Note: for DCCH/DTCH transmission, HS-SCCH shall be HS-SCCH order; while for BCCH transmission, the association and timing between HS-SCCH and HS-DSCH is the same as described in subclause 7.2.7.1.
Figure 25A: Timing for PICH and HS-SCCH for different radio frame configurations for a given UE
7.2.7.4 PICH/ HS-DSCH Association and Timing
When the UE in URA_PCH or CELL_PCH state without a dedicated UE identity detects the PICH identifying PCCH transmission, the UE shall receive the corresponding HS-DSCH TTIs. The association and timing between PICH and HS-DSCH is depicted in figure 25B. If a paging indicator in a certain PICH block is set to ‘1’ it is an indication that UEs associated with this paging indicator shall read their corresponding sub-channel and consider that paging message is retransmitted in 2*m subframes where m denotes Paging Sub-Channel Size configured by higher layers which is the number of frames that each paging sub-channel occupies. The value NGAP>0 of frames between the end of the PICH block and the beginning of the HS-DSCH is configured by higher layers.
Figure 25B: Timing for PICH and HS-DSCH for different radio frame configurations for a given UE