A self orienting liner hanger system including a bent sub, an indexing sub in operable communication with the bent sub, a hanger assembly in operable communication with the indexing sub, and a profile connected with the hanger assembly. The patch-type extrinsic Fabry-Perot interferometric fiber optic sensor is provided by combining the existing EFPI fiber optic sensor with a direction-detecting sensor which can acquire direction information of a strain of a structure, which can solve a signal distortion problem occurring in the existing EFPI fiber optic sensor through a simple signal process. The feedback circuit provides a feedback signal when a frequency of AC voltage across the sense capacitor substantially reaches the resonant frequency of the LC output filter so as to actively damp the voltage across the load. Links may be turned on and turned off. Power from the power island to the processing module may be reduced or secured when the one or more functions associated with the power island is not required.