Yup. Same principle. Basically, an RWR (Radar Warning Receiver) picks up the radar signal and lets you know the strength and direction of the source. By intelligence, research, trial and error, etc… enemies collect radar signatures and characterize them to use in the RWR technologies. That’s why “frequency hopping” is such a big deal. By constantly changing radar frequencies, it can confuse an RWR of it’s strength, search pattern and if lucky, whether or not it’s a friendly source. In the case of attacking ground radars, the HARM missile locks onto the radar on the ground and basically, follows it to the source. The faster you can make the missile break it’s lock, the better your chances of survival, as the HARM has a “memory” and will travel to it’s best possible source that it has determined.