Chimmalgi Shrinivas, Wahls Sander
Delft Center for Systems and Control, Delft University of Technology, Mekelweg 2, 2628 CD Delft, The Netherlands.
Entropy (Basel). 2020 Jun 9;22(6):639. doi: 10.3390/e22060639.
The performance of various nonlinear frequency division multiplexed (NFDM) fiber-optic transmission systems has been observed to decrease with increasing signal duration. For a class of NFDM systems known as -modulators, we show that the nonlinear bandwidth, signal duration, and power are coupled when singularities in the nonlinear spectrum are avoided. When the nonlinear bandwidth is fixed, the coupling results in an upper bound on the transmit power that decreases with increasing signal duration. Signal-to-noise ratios are consequently expected to decrease, which can help explain drops in performance observed in practice. Furthermore, we show that there is often a finite bound on the transmit power of -modulators even if spectral singularities are allowed.
已观察到各种非线性频分复用（NFDM）光纤传输系统的性能会随着信号持续时间的增加而下降。对于一类被称为 - 调制器的NFDM系统，我们表明，当避免非线性频谱中的奇点时，非线性带宽、信号持续时间和功率是相互耦合的。当非线性带宽固定时，这种耦合会导致发射功率的上限随着信号持续时间的增加而降低。因此，预计信噪比会下降，这有助于解释在实际中观察到的性能下降。此外，我们表明，即使允许频谱奇点存在， - 调制器的发射功率通常也存在一个有限的上限。
