| 摘要 |
PURPOSE:To precisely control antenna directivity even if a beacon station stops to transmit by storing beacon wave tracking information to use it when said information is reduced. CONSTITUTION:A beacon wave summing signal received from a prescribed direction by the primary radiators 3, 3 which are located on symmetrical positions about the pattern focus F of a main reflector 1 is applied to a received field strength discriminator 10, and when the value of the summing signal is more than the threshold, an output from a synchronous detector 5 is applied to a main reflector driving means 2 through a changeover switch 12 and stored in a storing element 11. When the value of the beacon information summing signal is reduced less than the threshold, the switch 12 is turned through the discriminator 10 and the stored contents of the element 11 are applied to the means 2. Thus even if a beacon station stops to transmit, antenna directivity can be precisely controlled without the mistake of noise signals or the like. |
