HS-DSCH may use either QPSK or 16-QAM. In the later sections, in this chapter, we discuss higher-order
modulation schemes (i.e., 64-QAM) that are added for certain deployment scenarios. Note the HSPDSCH
does not carry Layer 1 controls information; all relevant Layer 1 information is transmitted
on the associated HS-SCCH. Moreover, while HSDPA services are provided, the uplink/downlink
WCDMA link must be established to maintain a communication link.
High-Speed??“Shared Control Channel (HS-SCCH). The SF is fixed at 128. The channelization
codes used for HS-DSCH are allocated as follows: For X multicodes at offset Y, the codes are allocated
contiguously.
This information is signaled over the HS-SCCH. This channel can be scrambled by either the primary
or a secondary code. The time slot and subframe structure is given in Fig. 7.110.
CCH,16,YcCCH,16,YX1
430 CHAPTER SEVEN
FIGURE 7.110 HS-SCCH time slot and subframe structure.
Data = NData Bits Data
2560 Chips
Slot #1 Slot #0 Slot #2
Subframe = 2 msec
The information carried in the HS-SCCH physical channel is used to not only alert the specific UE
the data is intended for, but also supply the UE receiver with some physical layer information, so it
can prepare to demodulate the HS-DSCH channel.
Pages:
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705