Also, advanced types of radar, as ISAR, can provide images of the target, reflected as "classification" flag in Harpoon ANW, I think.
http://en.wikipedia.org/wiki/Inverse_synth..._aperture_radar
SAR and ISAR radars are in the H4.1 rules too.
When contacts are detected by a radar that classified as SAR or ISAR, the detected aircraft and ships can be classified by type or class, and ground targets can be identified.
Dave
Thanks I just thought it would be possible with ordinary radar differentiate between contact sizes.