In addition to radar, gps, gyro.. they likely also have terminal guidance radio very similar to what airports use for guiding airplanes to the runway in fog/clo

In addition to radar, gps, gyro.. they likely also have terminal guidance radio very similar to what airports use for guiding airplanes to the runway in fog/cloud. See Instrument Landing System. They may use active radar reflectors, and if they do, I'd say that's a different form of the same basic idea (using fixed radio sources to calculate an expected landing position.)