单项选择题
A.1×NPCH B.2×NPCH C.3×NPCH D.4×NPCH
A.CS域2G->3G切换 B.CS域3G->2G切换 C.PS域2G->3G重选 D.PS域3G->2G重选
A.QPSK B.8PSK C.16QAM