Real-time heterodyne fiber polarimetry with narrow- and broad-band sources

A fast heterodyne polarimeter for fiber characterization is presented. The measurement principle gives rise to two basic system versions, suitable for a wide range of experimental conditions. The first solution, useful in the case of narrow-band sources, is based on a self-heterodyne configuration. The second scheme, free from coherence requirements of the source, employs a Mach-Zehnder interferometric structure placed at the output of the fiber. Very good performances of both implementations are extensively demonstrated through different sets of results (in time and frequency domain) related to statical and dynamical fiber tests. Other relevant applications in telecommunication and sensor areas are discussed.