下列叙述中正确的是（ ） Which of the following statements are correct? A.在TD-SCDMA系统中每20MS为一个无线帧 In the TD-SCDMA system, every 20ms forms a radio frame B.在TD-SCDMA系统中每10MS为一个无线帧 In the TD-SCDMA system, every 10ms forms a radio frame C.每个无线帧可以分成2个子帧 Each radio frame is divided into 2 subframes D.每个无线帧可以分成4个子帧 Each radio frame is divided into 4 subframes
