Patent ID: 7142871

Claim:
A virtual image eliminating apparatus at the time when the position of a radio wave transmitting source is measured, comprising: plural bearing measuring instruments, positioned at different places each other, for measuring data being a bearing line and a reception level of a radio wave transmitted from said radio wave transmitting source; and a controlling and displaying instrument for displaying the position of said radio wave transmitting source by processing data, which were measured at said plural bearing measuring instruments and were transmitted to said controlling and displaying instrument, wherein: in case that intersection points formed by said bearing lines from said plural bearing measuring instruments are two or more, said controlling and displaying instrument calculates estimated radio wave transmitting intensity in all of the combinations of bearing lines, which formed one of said two or more intersection points, and judges whether each of said two or more intersection points is a real image or a virtual image based on the difference between said estimated radio wave transmitting intensity in one combination of said bearing lines formed one of said two or more intersection points.