 Unlike Blue Envoy, Bloodhound was expected to be able to see the target through the entire attack.Guidance was semi-active radar homing, with an illuminator radar lighting up the targets, and a receiver in the missile using the reflected signal to track.For this to work, the illuminator had to be pointed at the target using information from a separate tactical control radar, and the receiver in the nose of the missile had to be pointed at the target.