单项选择题在MPSK中克服相位模糊度问题的措施是 A、MDPSK B、锁相环准确恢复载波信号 C、窄带滤波器提取载波 D、非线性变换产生离散载频分量
单项选择题Any changes in field development strategies or production operation practices, however, could change the production trends of a well and significantly affect reserve estimates from decline-curve techniques. A. 对 B. 错