,512,n-1 in the Node B, again because we need time adjustment usage. However, this restriction does not apply to softer handover operation or when the UTRAN synchronizes to such a level that timing adjustments in soft handover are not applied in conjunction with SF 512. If we do implement compressed mode by reducing the spreading factor by 2, the OVSF code used for compressed frames is: Cch,SF/2,Ln/2_ when applying ordinary scrambling code, and Cch,SF/2,n mod SF/2 when applying alternative scrambling, where Cch,SF,n corre- sponds to the channelization code used for non-compressed frames. If the OVSF code on the PDSCH varies from frame to frame, the OVSF codes alloca- tion will occur in a way that the OVSF code(s) below the smallest spreading factor will be from the branch of the code tree pointed by the smallest spreading factor used for the connection. This implies that all the UE-PDSCH codes connecting can originate accord- ing to the OVSF code generation principle from smallest spreading factor code used by the UE on PDSCH. When mapping the DSCH to multiple parallel PDSCHs, the same rule applies. How- ever, all of the branches identified by the multiple codes, corresponding to the smallest spreading factor, may be used for higher spreading factor allocation [8]. 4.3.12.2 Downlink Scrambling Codes In principle, we can generate about 218-1 = 262 143 scrambling codes, numbered 0,...,262 142. However, we do not use all the scrambling codes. The specifications di- vide these scrambling codes into 512 sets each of a primary scrambling code and 15 secondary scrambling codes. The primary scrambling codes consist of n = 16 X i where = 0,...,511. The ith set of secondary scrambling codes consists of 16 X (i + k), where k = 1,...,15. There exists a one-to-one mapping between each primary scrambling code and 15 secondary scrambling codes in a set such that the ith primary scrambling code corresponds to the ith set of secondary scrambling codes. Thus, based on the principles above, we can use k = 0,1,...,8191 scrambling co