摘要 : A mathematical model of a cavity ring-down (CRD) fibre amplified loop gas sensing system is initially proposed. A digital least mean square (LMS) adaptive filter is designed and demonstrated the reduction of the detection error du... 展开 A mathematical model of a cavity ring-down (CRD) fibre amplified loop gas sensing system is initially proposed. A digital least mean square (LMS) adaptive filter is designed and demonstrated the reduction of the detection error due to an amplified spontaneous emission (ASE) noise which is induced by an erbium doped fibre amplifier (EDFA) in the CRD loop. The simulation results show that the detection error of 16 ppm is obtained. 收起