A facility for UWB antenna measurements in time domain

The IRCTR, Delft University of Technology (TU Delft), Netherlands, and the Bandung Institute of Technology (ITB), Indonesia, have been collaborating in a research project on the development of ultra-wideband (UWB) antennas for ground penetrating radar (GPR) applications. In the research, a facility for UWB antenna measurements in the time domain is needed. The paper describes such a facility which has been developed at ITB in the framework of the collaborative project. The UWB antenna measurement facility has been developed based on a technique introduced and implemented by IRCTR (Lestari, A.A., PhD Dissertation, TU Delft, 2003). Additionally, a feature for measuring radiated transient fields using a vector network analyser (VNA) has been included due to the unavailability of time-domain measuring equipment, such as pulse generators and sampling oscilloscope. The measurement facility has been used for measurements of the radiated near fields and input impedance of the UWB GPR antennas developed by IRCTR and ITB (Lestari et al., Proc. 10th Int. Conf. on Ground Penetrating Radar, GPR 2004, vol.1, p.141-4, 2004).