Unitary checkerboard precoded OFDM for low-PAPR optical wireless communications

Future 6G wireless networks will once again have to raise the performance in most technology domains by a factor of 10–100. Depending on the application, future requirements include peak data rates of 1 Tb/s per user, 0.1 ms latency, less than one out of a million outage, centimeter accurate positioning, near zero energy consumption at the device, and operation in different environments including factories, vehicles, and more. Optical wireless communications (OWCs) have the potential to provide ultrahigh data rates in a cost effective way, due to the vast and freely available light spectrum, and the availability of devices for transmitters and receivers. 5G New Radio architecture permits the integration of stand-alone OWC nodes on network layers. Current 6G research investigates advanced physical layer designs including OWC-compatible waveforms. In this context, in this paper, a new precoded orthogonal frequency division multiplexing (OFDM) waveform is proposed that is tailored to OWCs’ specific needs. Its prime advantage compared to OFDM is the ultralow peak-to-average power ratio, while preserving other benefits, such as high spectral efficiency, flexible subcarrier nulling, and low computational complexity.