Feasibility of an IFM-based system for broadband tunable gain slope equalization

Broadband microwave receivers with electronic warfare applications often exhibit frequency variations that degrade performance. Most notably, a negative gain slope is inherent to an RF/Microwave receiver chain, in-part, because of attenuation that results from frequency-dependent ohmic losses in the dielectric. We present a novel approach to tunable gain slope equalization that solves this problem by taking advantage of the existing IFM capability in an electronic warfare receiver. The demonstrated 0.4-2.4 GHz system circumvents problems associated with impedance mismatch, and offers an efficient means to tune the gain slope. In this feasibility assessment, we discuss the theory, measurement results, and challenges associated with practical IFM-based gain slope equalization. We also extend this discussion into an evaluation of the challenges of increasing the system's unambiguous bandwidth.