The Evolution of Optical OFDM

Abstract

Optical Orthogonal Frequency-Division Multiplexing (O-OFDM) is eminently suitable for mitigating the multi-path and chromatic dispersion in both Visible Light Communications (VLC) and Optical Fiber Communications. We commence our discourse by surveying the conception and historic evolution of O-OFDM designed for both VLC and optical fiber, culminating in the birth of its most flexible design alternative, namely Layered Asymmetrically Clipped Optical OFDM (LACO-OFDM). We demonstrate that it is eminently suitable for intensity-modulation and direct-detection aided optical communication systems and characterize its design flexibility. It is also shown that given its flexibility, it subsumes a wide range of optical OFDM schemes conceived over the past two decades or so. The LACO-OFDM transmitter and receiver designs strike a compelling compromise between the features of the popular Asymmetrically Clipped Optical OFDM (ACO-OFDM) and Direct Current Offset OFDM (DCO-OFDM). The pivotal role of forward error correction (FEC) designs is also surveyed with the objective of striking a coding gain versus complexity trade-off. We conclude by highlighting a suite of promising techniques capable of further improving the system performance, but require further research. The take-away message of the paper crystallized in the associated design guidelines.

The Evolution of Quantum Key Distribution Networks: On the Road to the Qinternet

“…2) The evolution of optical OFDM systems was documented in [604] and these guidelines may be used for designing the optical quantum links.…”

Joint Dimming Control and Optimal Power Allocation for THO-OFDM Visible Light Communications

“…For LACO-OFDM, the iterative receiver structure leads to the highest CC although still less than 5 times of ACO-OFDM, on the other hand, the demodulation delay climbs up constantly with the increment of loop times. However, the time delays at the transmitter are all the same because a parallel structure can be employed to send data at the same time [43]. For RPO-OFDM, it rarely supports a continuous dimming level (i.e.…”

“…signal to noise ratio (SNR). A number of mitigation schemes have been proposed to address the nonlinearity [43]. Thus the relationship between the forward current I and the forward voltage V (also between the power P and the I) can be quasi-linear over a limited range of [V L , V H ], where V L and V H denotes the turn-on and the maximum allowable voltages, respectively.…”

Unitary Checkerboard Precoded OFDM for Low-PAPR Optical Wireless Communications

“…Coded Schemes More recently, Single Carrier Generalized Time Slot Index Modulation (SC-GTIM) [38] and Layered Asymmetrically Clipped Optical OFDM (LACO-OFDM) [39] that combine modulation and coding have been proposed. SC-GTIM encodes the information on the amplitudes and positions of pulses and then, a set partitioning algorithm is proposed to construct a codebook.…”