Proposal for eliminating the external disturbance via digital PGC technique in a multiplexed fiber interferometer measurement system

A disturbance-free surface profile measuring system with sinusoidal phase integrating-bucket modulation

“…As reported in Ref. [10], the sine and cosine value of 2a 0 + 2d(t) can be demodulated using PGC [12,13] method, then the fast arctangent calculation of 2a 0 + 2d(t) can be achieved using CORDIC [14]. The PGC method which is complicated, takes too much time consumption.…”

“…Besides, we build up a feedback subsystem to eliminate external disturbances in fringes. Unlike the method described in [10], in which the phase generated carrier (PGC) [12] method is applied to extract the phase and calculated by arctangent calculation using coordinated rotation digital computer (CORDIC) [14], we extract the phase using peak detection method and count it out by arcsine calculation. In Section 5, we check the performance of the eliminating external disturbances in fringes, and confirm the applicability of the proposed method by measuring the surface profile of an aluminum plate with a size of 100 Â 100 pixels.…”

Research on An Improved Phase Generation Carrier Demodulation Algorithm

“…The phase demodulation algorithms of interferometric optical fiber sensors mainly include phase generation carrier (PGC) demodulation method, optical path matching differential interferometry, differential delay heterodyne method, etc. [1][2][3][4][5]. Among them, PGC demodulation method has gradually become the research hotspot because of its large measurement range, good linearity and high accuracy [6].Traditional PGC demodulation methods mainly include differential cross multiplication (DCM) and arctangent demodulation method (Arctangent) [7][8].Both of these algorithms are effected by modulation depth C and carrier phase delay θ, resulting in distortion of demodulated signal.…”