Abstract: A method and apparatus for transponding pulsed RF signals is provided. The method comprises receiving, with a receiver, pulsed RF signals having a plurality of PRIs. Further the method includes generating, with a PRI tracker, control signals from the received pulsed RF signals. The method then filters the received pulsed RF signals with the control signals to thereby obtain enable signals, which in turn control a transmitter permitting retransmission without clock jitter.

Abstract: A method and apparatus is provided for remotely and constantly calibrating a transponder by using the ring around phenomenon. A number of different time varying physical quantities, such as for example temperature, signal level, noise, transmission line flex, frequency, and general operational effects, affect the inherent delay in transponders on a time varying basis. The invention relies on a the ring around phenomenon to produce pulse doublets, wherein the distance between the pulses in the pulse doublets correspond to the instantaneous delay in the transponder. The system is configured so that instantaneous variation in the transmission delay is detected and recognized on a pulse by pulse basis and transmitted to the interrogation device, which then functions to calculate the actual delay. Normal operation of the transponder is not affected by the continuous calibration method, and therefore a special calibration mode is not required.

Abstract: A method and apparatus is provided for remotely and constantly calibrating a transponder by using the ring around phenomenon. A number of different time varying physical quantities, such as for example temperature, signal level, noise, transmission line flex, frequency, and general operational effects, affect the inherent delay in transponders on a time varying basis. The invention relies on a the ring around phenomenon to produce pulse doublets, wherein the distance between the pulses in the pulse doublets correspond to the instantaneous delay in the transponder. The system is configured so that instantaneous variation in the transmission delay is detected and recognized on a pulse by pulse basis and transmitted to the interrogation device, which then functions to calculate the actual delay. Normal operation of the transponder is not affected by the continuous calibration method, and therefore a special calibration mode is not required.

Abstract: A method and apparatus for transponding pulsed RF signals is provided. The method comprises receiving, with a receiver, pulsed RF signals having a plurality of PRIs. Further the method includes generating, with a PRI tracker, control signals from the received pulsed RF signals. The method then filters the received pulsed RF signals with the control signals to thereby obtain enable signals, which in turn control a transmitter permitting retransmission without clock jitter.