1. RNC在RRC Connection Setup消息中会告知UE上行信道应使用的SF。
2. 根据25.213,章节4.3.1.2.1,当SF确定后,具体码字的使用遵循如下规则:
For the DPCCH and DPDCHs the following applies:
- The DPCCH shall always be spread by code cc = Cch,256,0.
- When only one DPDCH is to be transmitted, DPDCH1 shall be spread by code cd,1 = Cch,SF,k where SF is the spreading factor of DPDCH1 and k= SF / 4.
- When more than one DPDCH is to be transmitted, all DPDCHs have spreading factors equal to 4. DPDCHn shall be spread by the the code cd,n = Cch,4,k , where k = 1 if n 属于 {1, 2}, k = 3 if n 属于 {3, 4}, and k = 2 if n 属于 {5, 6}.