High Power Short Pulse Transmit/Receive Isolation Device

The main objective of this Phase-II effort is to build upon the results of our Phase-I effort to design, fabricate and demonstrate the performance of wideband “circulator” or a 3-port directional coupler. The current work is also being undertaken in an effort to improve the technology associated with the hardware used in the PING program. Currently, the PING program is using a bi-static arrangement with separate transmit and receive antennas. The frequency range of interest is between 150 MHz and 2 GHz. A major technological barrier to the success of the PING program is rooted in the cross-talk between the transmit and receive antennas. One approach to reducing or eliminating the cross-talk is to configure the system with one antenna (mono-static) that is coupled to both the transmitter source and the receive instrumentation through a directional coupler. The work in Phase I has demonstrated the feasibility of such a directional coupler. Additionally, Phase I research has demonstrated the feasibility of using a gas breakdown switch to further protect the sensitive (and expensive) receive instrumentation from any over volt transients that may occur. During Phase II, both of these technologies will be developed and demonstrated in a complete mono-static transmit/receive system.