QAM Transmission System Based on Heterodyne Optical Detection using Intermediate Frequency Carrier Modulation
Compared with the optical communication system using intensity modulation with direct detection (IM-DD), the coherent optical system enhances the sensitivity and enables access to all the optical characteristics. In this paper, a novel scheme of coherent QAM transmission system based on heterodyne optical detection is experimentally demonstrated. In the proposed scheme, the intermediate frequency (IF) carrier modulation at double-sideband suppressed carrier (DSB-SC) mode at the transmitter side enables demodulation of QAM signal with heterodyne detection. Furthermore, the receiver is simplified by avoiding the use of high frequency broadband microwave devices due to the employment of IF carrier modulation. The performance of the proposed coherent QAM system is analyzed theoretically based on numerical simulation. The simulation results show that the improved structure of the proposed system can effectively depress the phase noise induced by laser. An experiment of 4-QAM transmission exploiting the proposed coherent heterodyne system is presented to justify the principle.
Coherent optical communication heterodyne detection quadrature amplitude modulation (QAM) intermediate frequency (IF) carrier
Ran Zhu Kun Xu Ye Zhang Yan Li Jian Wu Xiaobin Hong Jintong Lin
Key Laboratory of Optical Communication and Lightwave Technologies,Ministry of Education,Beijing University of Posts and Telecommunications,Beijing,100876,China.
国际会议
2008亚太光通信会议(Asia-Pacific Optical Communications 2008)
杭州
英文
2008-10-26（万方平台首次上网日期，不代表论文的发表时间）