| 摘要 |
The invention relates to a radio transponder ( 200 ) for reception and retransmission of electromagnetic energy, particularly in the microwave range. The transponder comprises a connection ( 210 ) to an antenna, a control circuit for modulation ( 260 ), a detector ( 250 ), a delay element ( 240 ) and a first semiconductor switch ( 220 ). The transponder comprises, in addition, a second semiconductor switch ( 230 ), and the control circuit for modulation ( 260 ) is arranged to be able to control the semiconductor switches ( 220, 230 ) independently in such a way that a signal that comes in via the antenna connection ( 210 ) can be caused to be reflected on either side of the delay element ( 240 ) or to pass through this to the detector ( 250 ). At least one of the semiconductor switches ( 220, 230 ) is suitably a diode or a transistor. |
