64-Gb/s SSB-PAM4 Transmission Over 120-km Dispersion-Uncompensated SSMF With Blind Nonlinear Equalization, Adaptive Noise-Whitening Postfilter and MLSD

3.8 Gb/s PAM-4 UOWC System Over a 2-m Underwater Channel Enabled by a Single-Pixel 175-μm GaN-Based Mini-LED

“…A noise-whitening post-filter that consists of a finite impulse response (FIR) equalizer is used to whiten the colored noise. The autoregressive (AR) method based on Yule-Walker equations is used to get the kernel coefficients of the noise-whitening post-filter [28]. The kernel coefficients of noise-whitening postfilter can be expressed as Eq.…”

“…Furthermore, to obtain the trade-off between the modulation bandwidth and optical power, a 175-µm 580 MHz blue mini-LED is designed and fabricated based on a standard c-plane, which is used as the optical source for a 2-m UOWC system. On the receiver side, the BER can be significantly decreased by a low-complexity VE based on the targeted principal component analysis (TPCA) and adaptive noise-whitening post-filter with MLSD compared to the traditional feedforward linear equalizer (LE) [27,28]. In addition, the impact of the operating parameters, including the driving current of the mini-LED and the modulation depth (peak-to-peak voltage, Vpp) of the input RF signals, are characterized in detail to maximize the capacity of the UOWC system.…”

A Review of Self-Coherent Optical Transceivers: Fundamental Issues, Recent Advances, and Research Directions

“…Another attractive modulation scheme that has been gaining significant recognition for different applications is the single-sideband (SSB) modulation. For instance, the SSB-DMT, SSB-PAM4, and SSB-CAP schemes have been gaining significant attention [53,[82][83][84][85]. This is mainly due to the notable offered advantages such as the improved SE and significant resistance to chromatic dispersion because of the EDC capability [55,56].…”

56 Gbit/s OOK Signal in C-band Over 20 km Dispersion-Uncompensated Link Transmission With Receiver-Side EDC Algorithm

“…Furthermore, for compensating the loss, extra optical amplifiers may be required thus increasing the cost and reducing the optical signal-to-noise ratio of the system [4]. There exist other solutions for compensating CD, such as complex-valued singlesideband modulation [5], CD pre-compensation at the transmitter side [6] and Kramers-Kronig receiver [7]. However, the use of either extra resource or complicated transmitter configurations are required when using these methods.…”