频[率]调[变]调频
frequency modulation {= FM
脉冲频率调制
pulse frequency modulation
PFM
pulse-frequency modulation
Pulse Frequency Modulation PFM
bearer instrument
Pulse-frequency-modutation (PFM
pulse-freqnecy modulation
permutation indexpulse frequency modulation
双音调调变频率
dual tone modulation frequency
变频脉冲信号产生器
frequency pulse signal generator
变斜率脉冲调制
variable-slope pulse modulation
步进频率脉冲信号
frequency-stepped pulse signal
调频脉冲扫频信号
frequency modulated pulse sweep
高功率重复频率脉冲驱动源
high power repetition frequency drive source
积分脉波频率调变
integral pulse frequency modulation