A novel simulation method of passive intermodulation in electrically large-size reflector antennas

摘要

As a well-known and wide-range electromagnetic compatibility problem, passive intermodulation (PIM) caused by nonlinearities remains a considerable potential risk for high-power transceiver communication systems. A three-dimensional field-circuit mixed simulation method for the prediction of PIM in electrically large-size deployable reflector antennas is presented in this work. Based on the accurate electromagnetic field calculation and an equivalent nonlinear circuit analysis, a novel simulation method for PIM analysis is proposed, which shows universality in PIM analysis of passive microwave devices. This method solves the calculation challenge caused by the dimension discrepancy between the electrical contact of nanometers and the reflector of tens of centimeters through establishing the field-to-circuit equivalent model. PIM arisen from nonlinear electrical contacts bas been modeled by an equivalent behavior model and the inaccuracy caused by the background noise and calculation error is avoided. Simulation results demonstrate that low-order PIM of a deployable reflector antenna of 15 meters is calculated successfully and match with experimental results.