A Novel Multi-Level Constellation Compression Modulation for GFDM-PON

In this paper, for the first time, a novel multi-level constellation compression modulation (MCCM) is proposed and applied for generalized frequency division multiplexing passive optical network (GFDM-PON). The principle of the proposed MCCM is to transfer the constellation points of the outer circle to the ones of the inner circle with different probabilities, thereby significantly reducing the average transmitted power. Also, by dynamically adjusting the compression factor, MCCM can also achieve different types of constellations to accommodate various scenarios of optical fiber transmission. In order to verify the feasibility of the proposed coded modulation technology and its transmission performance, a GFDM-PON system is set up based on intensity-modulation and direct-detection. The experimental results indicate not only that one-level constellation compression modulation (CCM) is superior to the conventional modulation technology, but also two-level CCM can significantly reduce the bit error ratio (BER) of the system. When the transmission performance is unfavorable, the system BER can be further reduced by the enhanced CCM. Therefore, the system based on the proposed MCCM technology can meet different access scenarios with robust adaptability and scalability.