Patent ID: 6759982
Filing Date: 2004-07-06
Classification: G01S,H01Q

Abstract:
A radio direction and position finding apparatus comprising;a first directional antenna which rotates with a desired angle elevation; a first phase integral means for producing an output through an integration of output from said directional antenna; a first phase difference means for producing an output as a difference of the outputs from said first directional antenna; a first frequency dividing means for dividing frequency of integral component of the output from said directional antenna; a first differential gain control means for controlling gain of differential component of the output from said directional antenna; a first receiving means for receiving output from said first frequency dividing means and producing a detection signal output; a second receiving means for receiving output from said first differential gain control means and producing a detection signal output; a first subtraction means for subtracting one detection signal output from the other detection signal output of said first and second receiving means; a first calculation means for determining a direction of arrival of radio wave based on output from said first subtraction means; a second directional antenna which rotates with a desired angle of elevation; a second phase integral means for producing an output through an integration of output from said second directional antenna; a second phase difference means for producing an output as a difference of the outputs from said second directional antenna; a second frequency dividing means for dividing frequency of integral component of the output from said second directional antenna; a second differential gain control means for controlling gain of differential component of the output from said second directional antenna; a third receiving means for receiving output from said second frequency dividing means and producing a detection signal output; a fourth receiving means for receiving output from said second differential gain control means and producing a detection signal output; a second subtraction means for subtracting one detection signal output from the other detection signal output of said third and fourth receiving means; a second calculation means for determining a direction of arrival of radio wave based on output from said second subtraction means; and a position determining calculation means for determining the position of the emission source of the radio wave based on outputs from said first and second calculation means; wherein said directional antenna and said second directional antenna rotate interlockingly.