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The emerging concept of structural health management relies on extensive onboard diagnostic sensors that can provide near real-time information about the state of a structure so that informed prognostic assessment can be made of the continuing reliability of the structure.In this talk, we will describe ongoing efforts at Northwestern University in the area of fiber-optic sensors for structural health monitoring.In the past, we have demonstrated that Fiber Bragg Grating (FBG) sensors can be used to monitor not only quasistatic and low frequency parameters such as strain, temperature, and vibration, but also high frequency dynamic strains such as due to impact or acoustic emission.These systems were based on a novel two-wave mixing demodulator that provided adaptivity to low frequency drift of the sensor as well as multipexibility to demodulate dynamic signals from multiple sensors in one single demodulation system.However, one major limitation of this system was the necessity for an erbium-doped optical amplifier which increases the cost of the demodulator and limits the number of FBG channels that can be processed.To overcome this, we have previously attempted an adaptive ring laser source that has optical power only at the wavelengths of the FBG sensors.However, with Er-doped fibers at the C-band, the relaxation times are not fast enough to avoid system instability.In this paper, we discuss our current effort to move the adaptive source to the ~1064nm range where the Yb-doped ring laser systems are expected to have an order of magnitude faster relaxation time, thereby avoiding system instability.We propose to integrate this adaptive source with a fiber-based TWM adaptive demodulator to provide a low-cost high frequency multipexable FBG demodulation system.