Optical performance monitoring technique using delay tap asynchronous waveform sampling

Signed frequency offset measurement for direct detection DPSK system with a chromatic dispersion offset

“…Asynchronous delay-tap sampling technique has been recently proposed for multi-parameter monitoring [9,11,12]. Delay-tap sampling method employs a delay line tap to sample twice with a fixed delay in one sampling process to obtain a pair of data.…”

“…In this paper, we demonstrated a method for measuring signed frequency offset based on delay-tap sampling technique [9] with a chromatic dispersion (CD) offset. The demodulated signal shows asymmetric distortions and amplitude shoulder appears on either the trailing or leading edge with frequency and CD offsets, which is reflected in the corresponding delay-tap plots.…”

Monitors to Ensure the Performance of Photonic Networks

“…Many groups are actively engaged in developing new techniques to meet the needs of these networks [6][7][8][9] An example of one promising technique for monitoring signal quality is the Quasi-BER monitor, or Q-BER [10,11]. In the laboratory environment the best way to characterize a signal's quality after transmission is to measure its Q [12].…”

Enabling ASON Routing via Novel Signal Quality Metrics

“…G k is the net gain/loss of the k-th link and L Res (dB) is the residual loss before the receiving node. The parameters required to estimate the ECP can be looked up in a database or directly measured [13], so each link in a network can be represented by a vector of the form (P ASE,j , D j , ∆τ j ). These vectors are used as the basis of the "cost metric" in the path selection algorithm described in the next section.…”