  We demonstrate incoherent broadband cavity enhanced absorption spectroscopy
in the mid-infrared wave- length range from 3000 to 3450 nm using an all-fiber
based supercontinuum source. Multi-components gas detection is performed and
concentrations of acetylene and methane are retrieved with sub-ppm accuracy. A
linear response to nominal gas concentrations is observed demonstrating the
feasibility of the method for sensing applications.
