fixed depth signal source定深信号源
fixed cycle signal定周期交通信号
fixed d signal固定信号
fixed time signal定时信号灯
Fixed type signal light信号灯
automatic isolated fixed cycle signal固定周期自动信号
fixed-time signal[交] [电子] 定时信号
fixed time traffic signal定时交通信号
FSS Fixed Signal Services固定信号服务