$3\times 2 ^{N}$-QAM Constellation Formats for DMT Over 1-mm Core Diameter Plastic Optical Fiber

The family of 3 × 2
^N
quadrature amplitude modulation (QAM) constellations in combination with discrete multitone modulation is employed to maximize the throughput of 1-mm core diameter plastic optical fibers. Using this scheme together with a bit and power loading algorithm, a bit-rate improvement of 12% is achieved compared with using only 2
N
-QAM scheme. A bit rate of 5.6 Gb/s is demonstrated over 50 m of 1-mm core diameter graded-index plastic optical fiber (POF).