對干涉型光纖傳感器的分集檢測消偏振衰落技術(shù)進(jìn)行了理論分析，提出了將各路信號平方后相加的信號處理方式，使之能實(shí)現(xiàn)單元及陣列的實(shí)時(shí)消偏振衰落信號檢測。通過理論計(jì)算，可以使干涉信號幅度波動(dòng)小于4.7dB，并得出三路檢偏是分集檢測的最簡取值的結(jié)論，通過信號處理電路，能夠在信噪比略有降低的情況下消除偏振衰落的影響，實(shí)現(xiàn)干涉型光纖傳感器的消偏振衰落，并設(shè)計(jì)了用于陣列的分集檢測的實(shí)現(xiàn)方式。
關(guān)鍵詞： 光纖干涉儀; 光偏振態(tài); 傳感器陣列; 信號處理；分集檢測
Abstract: A theoretical analysis is carried out for the divide/combine depolarization-induced-fading technique of an interferometric fiber-optic sensor. A processing method that adds the squared signals from various channels and thus can achieve real-time signal detection of unit and array by means of depolarization-induced-fading technique is proposed. The theoretical calculation shows the maximum fluctuation amplitude of the interferometric signal can be less than 4.7dB and a conclusion that three-channel polarization is the simplest value of divide/combine detection is obtained. Through signal processing circuit, the effect of polarization-induced-fading technique can be eliminated and the depolarization-induced-fading of an interferometric fiber-optic sensor can be achieved with a few SNR dropping. The scheme of divide/combine detection used for array is designed.
Keywords: Optical fiber interferometers; Optical polarization; Sensor array; Signal processing； Divide/combine technique