This contribution deals with the accurate determination of the impulse response of ultra-wideband (UWB) antennas both by simulation and measurement. As can be found in recent literature, knowledge about the impulse response does not only allow for the derivation of further antenna parameters such as gain or group delay, but also to design more efficient receivers and to run more realistic simulations. Here we will use the example of a cone antenna as the antenna under test (AUT), as this is a very prominent antenna type in the field of UWB. In the first part, CST MICROWAVE STUDIO® (CST MWS) is used to model and simulate the transmitting antenna. To extract the radiated E-Field, we developed a new macro based on the transient broadband farfield monitor. Applying this macro is time-saving compared to the conventional method using farfield probes which can be found in many publications. The transmit impulse response is determined by a deconvolution operation. Finally Lorentz reciprocity is used to evaluate the receive impulse response as it is common in literature. In the second part the obtained simulation results from CST MWS will be compared to measurement results. At this we will not only use the conventional two-antenna method but we will also introduce the GTEM method, as a fast and accurate antenna measurement method. We developed this novel method based upon our previous research in the field of GTEM cells and it allows for a direct determination of the receive impulse response using a single antenna only.
Sebastian Sczyslo, Gunnar Armbrecht, Holger Thye, Sven Dortmund, Thomas Kaiser (Leibniz Universität Hannover)