Advanced RF Interferometry Structure for Improving Operation Range

Abstract

[EN] In this letter, a novel structure combining low coherence interferometry (LCI) and microwave photonics (MWP) is proposed. In this case, the electro-optic modulator is strategically placed inside the interferometric structure in order to modify the behavior of the whole MWP-LCI system. Specifically, limiting effects which are inherently generated as the DC term, the self-reflection term and the carrier suppression effect are avoided. This fact enables the improvement of the MWP-LCI operating range in comparison to previous proposals. Moreover, a detailed description of the MWP-LCI structure is addressed in this letter to support the corresponding experimental demonstration and theoretical development. In addition, typical LCI capabilities such as penetration depth, resolution, and sensitivity are also measured. For the MWP-LCI structure proposed here, a 1 cm penetration depth with a resolution of 120 mu m and a sensitivity beyond 50 dB are achieved.