Ultrahigh-speed “orthogonal” TDM transmission with an optical Nyquist pulse train

Abstract

We propose a novel "orthogonal" TDM transmission scheme using an optical Nyquist pulse that enables us to achieve an ultrahigh data rate and spectral efficiency simultaneously without any intersymbol interference (ISI). We analytically describe the principle of orthogonal TDM, and demonstrate a 160 Gbaud optical orthogonal TDM transmission using 40 GHz optical Nyquist pulses. Tolerance to GVD and the dispersion slope is significantly improved by virtue of the orthogonality, reduced bandwidth, and minimum ISI.

Residual dispersion equalization using correlation detection in Nyquist OTDM scheme

“…2, pp. 1129-1140, Jan. 2012. DOI:10.1364 [2] F. Ito, "Demultiplexed detection of ultrafast optical signal using interferometric cross-correlation technique,"…”

“…A Nyquist optical time division multiplexing (OTDM) scheme can realize low inter-symbol interference and high spectral efficiency with a high baud rate [1]. To achieve a high optical signal-to-noise ratio (OSNR) tolerance with high spectral efficiency, we previously proposed a Nyquist OTDM scheme based on correlation detection [2][3][4][5].…”

Nyquist OTDM scheme using optical root-Nyquist pulse and optical correlation receiver

“…A Nyquist optical time division multiplexing (Nyquist OTDM) scheme using an optical Nyquist pulse has been proposed to realize low inter-symbol interference (ISI) and high spectral efficiency with an ultra-high-speed transmission [1]. The scheme involves a trade-off between the signal-to-noise ratio (SNR) and ISI, because an ultrafast optical sampler is needed as a time gate to satisfy the Nyquist criterion.…”

“…The optical root-Nyquist pulses r(t)e jωct were generated using a mode-locked laser and an optical pulse shaping filter with the same generation technique as that used for the optical Nyquist pulse [1]. Then, the correlation receiver with optical root-Nyquist pulses is used as the root-raised cosine filter of the receiver.…”

Signal degradation due to finite integration time for correlation detection in Nyquist OTDM scheme

“…high-speed transmission [1]. To achieve high optical signal-to-noise ratio (OSNR) tolerance with high spectral efficiency, we have previously proposed a Nyquist OTDM scheme based on correlation-detection [2,3].…”