摘要 |
<p>PURPOSE:To secure a constant data rate as well as to increase the number of the pulse bit to the specified target by varying the radar transmission frequency with adding no special parts nor functions to the antenna. CONSTITUTION:Radiation elements A1-An are arranged on series feeder line length l with space d between. With variation of frequency f, the beam direction theta of the antenna shifts. And the direction of elevation angle is scanned via phase shifter B, and then the antenna has a mechanical turn clockwise by angle omegaO during time tO'-tO. If the beam direction from normal line 2 of antenna 1 is set to thetaO at normal using frequency fO, beam direction 4 shifts by omegaO from target 3 after tO'-tO. Accordingly, a variation is secured from frequency fO by a fixed amount so that thetaO' = thetaO - omegaO may be secured for the beam direction from normal line 2' when antenna state 1' is obtained. Thus, beam direction 5 turns toward target 3, increasing the number of the pulse bit.</p> |