English ⇄ Chinese Spanish

passive detection and ranging
earth.sc.	无源测向测距装置
el.	被动探测与测距
geophys.	无源探测和测距
mil., air.def.	无源探测与测距; 无源雷达
radio	被达; 无源探测系统
space	无源［被动］探测与测距

passive detection and ranging: 3 phrases in 2 subjects

Aviation	1
Electronics	2