| 摘要 |
A distress beacon 1 adapted to transmit a distress signal. The distress signal comprises a radio-frequency signal that is amplitude modulated by an audio-frequency sweep, or chirp, signal. A characteristic of at least one of the radio-frequency signal and the audio-frequency sweep signal is modulated by a data signal, so as to transmit additional information about the beacon 1. Also provided are a method of transmitting the signal and a receiver for receiving the signal. The data signal may comprise data provided by a satellite positioning receiver and/or information identifying the distress beacon. The distress beacon may be a EPIRB, ELT, PLB or man-overboard device. |
