| 摘要 |
PURPOSE:To enable a bearing detection with a small scale of a receiver mechanism construction by comparing amplitudes of received signals with two systems of receivers; one receiving signals with a broad antenna beam, and the other receiving signals with a narrow antenna beam. CONSTITUTION:The received amplitude level of a receiver 2 with a broad beam is in a relative relationship with the received amplitude level of a receiver 7 with a narrow beam. It is so set that the received altitude level of the receiver with the broad beam is at the intersection of adjacent narrow beams. When receiving a signal with a narrow beam B, the receiver 7 is given an output of a larger received amplitude level of the receiver 2. The angle DELTAtheta of bearing is determined from the value of the amplitude level difference LBW1 with the receiver 2 corresponding to the difference between the coming direction of the signal and the beam nose direction of the narrow beam. When the amplitude level difference LAW1 of an amplitude comparator circuit 8 is below the reference level L0, the incoming direction is determined to be theta1 while when above L0, it is determined to be theta2 whereby the incoming bearing of the signal can be determined unconditionally. Thus, this has an advantage of allowing the detection of the bearing with a small scale of a receiver construction. |
