A Novel Modulation Scheme Based on the Kramers–Kronig Relations for Optical IM-DD Systems

The increasing demand for higher data rates in optical communication systems, especially within data centers and backbone networks, calls for the development of advanced modulation formats that can significantly enhance system performance. In this work, we introduce a novel modulation format based on the Kramers–Kronig relations, designed to improve upon traditional techniques such as Pulse Amplitude Modulation (PAM) and Carrier-less Amplitude Phase (CAP) modulation. The novel modulation format was rigorously validated through experimental investigations using an optical wireless communication (OWC) link. The results demonstrate a notable improvement in bit error rate (BER) performance and receiver sensitivity when compared to the conventional PAM-4 modulation scheme and CAP-16 modulation schemes. Moreover, the proposed scheme effectively reduces the complexity of digital filtering required by CAP while lowering the demands on the Digital-to-Analog Converter (DAC), making it a more practical solution for high-speed optical communication. This advancement facilitates higher data transmission rates, proving the Kramers–Kronig relations modulation format as a promising alternative to existing methods. Its potential for enhancing the efficiency and capacity of optical communication systems is evident. Future research will focus on optimizing the modulation parameters and exploring their application in more complex scenarios, such as high-speed underwater visible light communication systems, where advanced modulation formats are crucial for overcoming bandwidth limitations.