Which radar gets its name from the fact that each echo pulse from the aircraft being tracked yields a new azimuth and elevation correction angle?

The radar system that is characterized by receiving a new azimuth and elevation correction angle from each echo pulse is known as monopulse radar. This method utilizes simultaneous reception of the echo return from multiple antenna beams, enabling it to determine the direction to the target quickly and accurately after just one pulse.

When a target is detected, monopulse radar can instantly calculate both the azimuth and elevation angles because it compares the strength of the signals received from the different beams. This results in a very fast and precise tracking capability, making it particularly useful in applications where rapid response is critical, such as in missile guidance and targeting systems.

The other options do not provide the same capability. Raster scan systems involve sweeping a beam over an area, which typically requires multiple sweeps to obtain full angular information. Helical scan radars employ a spiral movement, while conical scan radars use a conical pattern to gather tracking information but typically do so from a broader sequence of scans rather than from instantaneous multiple angle measurements of a single pulse.