本规范所说的空中接口是指UE和网络之间的Uu接口，由L1、L2和L3组成。L1是基于TD-SCDMA技术的，3GPP TS 25.200系列规范对L1进行了详细描述；L2和L3与UTRA TDD 模式相同, 相应的描述见3GPP TS 25.300和3GPP 25.400系列规范。 -The air interface standard is referred to the network between the UE and the Uu interface, the L1, L2 and L3. L1 is based on TD-SCDMA technology, 3GPP TS 25.200 series specification a detailed descr iption of the L1　L2 and L3 and the UTRA TDD mode, the corresponding descr iption see 3GPP TS 25.300 and 3GPP 25.400 series specifications.