| 摘要 |
A common antenna system for a primary and a secondary radar transceiver, designed for monitoring air traffic, has a primary feeder or source connected to a primary-radar transceiver and terminating in a horn confronting a reflector, this source including two transverse probes connected to a secondary-radar transceiver which also communicates with a pair of ancillary feeders flanking the horn in an azimuthal plane. The horn is also flanked by two dipoles, closer than the ancillary feeders, delivering a difference signal of a monopulse channel to an angular-deviation-measuring receiver to which an incoming sum signal of the same channel is fed from the probes by way of the secondary-radar transceiver. The signals of the monopulse channel are emitted by transponders aboard an aircraft in response to interrogation signals sent out and received back by the probes in a radiation pattern blanked for the most part by control signals transmitted and received by the ancillary feeders, these control signals leaving free an interrogation arc of limited azimuthal extent; the signals of the monopulse channel define a narrower angular-deviation-measuring arc for localizing an aircraft within the interrogation arc. |
