Beacon target processing for air traffic control

The beacon subsystem is one of many sources providing information to the air traffic control system. In automatic systems, various types of target information are derived from the beacon replies in a special purpose computer known generally as a processor. An important aspect of processor performance is its ability to detect targets in a noisy environment and to accurately determine the location of these targets. Among the important measures of target detector performance are the false alarm rate, the probability of detection, and azimuth accuracy. The intimate relationship between these three characteristics is described in this paper and specific examples are given using a sequential observer target detector. It is shown that increasing the range resolution of the system also benefits target false alarm rate and azimuth accuracy. Thus, as advances in technology permit improved range resolution, greater overall system performance can be expected. Nevertheless, with current technology, the azimuth accuracy which can be achieved with a statistical detector is better than the azimuth equivalent of one pulse repetition period even in a noisy environment.