| 摘要 |
PURPOSE:To return electromagnetic waves to many radars, by storing temporarily a high level pulse interval among received radar pulses, eliminating the same interval with a pulse of low level and allowing to respond to the other pulses, in a transponder. CONSTITUTION:Radars A, B exist in a short range and a long range of a transponder, the main and the side lobe of the radar A and the main lobe of the radar B are inputted to a video detecting circuit 12 via an antenna 10 and a circulator 11, the detected output is supplied to amplifier circuits 13, 14, the pulse of high level of the radar A received in the circuit 14 is amplified and inputted to an OR circuit 20, the interval is measured at a pulse interval measuring circuit 16, and the result is stored in a memory circuit 17. Further, all pulses are amplified in the circuit 13, the pulse interval is measured at the circuit 15, the count value is compared with the content of a memory 17 at a comparison circuit 18, and when they are coincident, the pulse is blocked at a block gate 19 and only the pulse of the radar B is passed through, and a code pulse is transmitted with the output of the OR20. |
