Research on the Application of Radio-over-Fiber in Bistatic Scattering Measurements

This paper systematically investigates the impact of two transmission links - radio frequency (RF) cable and fiber-optic - on measurement and imaging results in bistatic scattering tests. Based on a combined approach of electromagnetic simulation and compact range measurements, the performance differences among RF cable, 10-meter fiber, and 200-meter fiber links in bistatic RCS measurement and Paraboloid Back-Projection (PBP) imaging were compared and analyzed at X-band under identical geometric configurations. The results indicate that the imaging results from all three links can clearly resolve the scattering centers, with consistent image quality. Furthermore, time-series analysis of the direct leakage peak revealed phase fluctuations of less than 2° and 4° for the 10-meter and 200-meter fibers, respectively, with amplitude variations within 1 dB, demonstrating good phase stability. Finally, the observed variation of the direct leakage peak provides a potential method for compensating the error caused by the system in the target response. Through systematic comparative experiments, this study validates the feasibility of using radio-over-fiber links to replace traditional RF cables in bistatic scattering tests.