| 摘要 |
A predictive collision radar system (10) in a vehicle (16) incorporates a first antenna (22) and a guard antenna (24), the associated radiation patterns (44, 46) of which overlap with one another, but the radiation pattern (44) of the guard antenna (24) is broader than that of the first antenna (22). A comparison (718, 120) of signals from the first and guard antennas provides for rejecting targets that are not likely a threat to the vehicle (16). In one embodiment the first antenna (22) is a multi-beam antenna (22.1, 22.2) with an electromagnetic lens (40, 56), for example, either dielectric (40, 40.1) or planar (56), and a signal from a forward looking element (58) thereof is compared with the signal from the guard antenna (24) aligned therewith. In another embodiment, an electromagnetic lens (70) is adapted to cooperate with the guard antenna (24) so as to provide for redirecting the associated radiation pattern (44.1'). |
