| The automation of the impedance matching of radio frequency (RF) ports enables the test engineer to compensate the undesired effects, which are not uncommon in RF systems and make the impedance matching iterative, time-consuming, and an empirical process. Numerous reconfigurable matching networks have been presented for automated matching. However, the automation still relies on an iterative control to achieve a matching goal, because it lacks the knowledge of the RF target and the matching network. Our goals were to develop an automatic matching control system that uses this knowledge to set the impedance matching in a non-iterative fashion and to develop a method to extract circuit parameters systematically while keeping the additional necessary parts to a minimum. To achieve this goal, we use the principles of a reflectometer to extract knowledge of the RF target and various microwave modeling methods to characterize the matching network. Our results demonstrate the proposed ideas and include an automatic matching control using a tunable microstrip bandpass filter, a load estimation technique using the microstrip filter, a new lumped matching network for the automatic matching in embedded RF testing, and a new matching control algorithm using the load estimation. |
