中文摘要：

Light-emitting diode（LED）-based visible light communication（VLC） has become a potential candidate for nextgeneration ultra-high-speed indoor wireless communication. In this paper, four special-shaped 8-quadrature amplitude modulation（QAM） constellations are investigated in a single-carrier VLC system. It is numerically verified and experimentally demonstrated that circular（7,1） shows obvious superiority in the performance of the dynamic range of signal voltage peak-to-peak（vpp） value and bit error rate（BER）. Next best is rectangular, followed by triangular; circular（4,4） has the worst performance. A data rate of 1.515 Gbit/s is successfully achieved by circular（7,1） employing a red chip LED over 0.5 m indoor free space transmission below a BER threshold of3.8 × 10-3. Compared with circular（4,4）, the traditional 8-QAM constellation, circular（7,1） provides a wider dynamic range of signal vpp, a higher data rate, and a longer transmission distance. To the best of our knowledge,this is the first investigation into the performance differences of special-shaped 8-QAM constellations in a highspeed, single-carrier VLC system, and the results comprehensively demonstrate that circular（7,1） is the optimal option.

英文摘要：

Light-emitting diode (LED)-based visible light communication (VLC) has become a potential candidate for next-generation ultra-high-speed indoor wireless communication. In this paper, four special-shaped 8-quadrature amplitude modulation (QAM) constellations are investigated in a single-carrier VLC system. It is numerically verified and experimentally demonstrated that circular (7,1) shows obvious superiority in the performance of the dynamic range of signal voltage peak-to-peak (vpp) value and bit error rate (BER). Next best is rectangular, followed by triangular; circular (4,4) has the worst performance. A data rate of 1.515 Gbit/s is successfully achieved by circular (7,1) employing a red chip LED over 0.5 m indoor free space transmission below a BER threshold of 3.8 x 10(-3). Compared with circular (4,4), the traditional 8-QAM constellation, circular (7,1) provides a wider dynamic range of signal vpp, a higher data rate, and a longer transmission distance. To the best of our knowledge, this is the first investigation into the performance differences of special-shaped 8-QAM constellations in a highspeed, single-carrier VLC system, and the results comprehensively demonstrate that circular (7,1) is the optimal option. (C) 2016 Chinese Laser Press