| 摘要 |
<p>An apparatus for direction-finding a received radio signal is disclosed. The receiving apparatus selectively receives on a predetermined frequency to match the transmitter frequency. The receiving apparatus comprises of two or three antennas, including one or two loop antennas that work in conjunction with a third reference antenna (whose phase does not vary when its orientation changes relative to the transmitter), such as a dipole, monopole or helical antenna. By comparing the phase between the antennas the direction of the incoming RF signal can be determined. In some embodiments, the windings of the two loop antennas are wound in reverse with respect to each other in order to substantially double the sensitivity of the signal-detection capabilities.</p> |
