Study On The 160 Gb/s High-speed OTDM Systems And Their Transmission Performance

Optical time division multiplexing (OTDM) is a technology in which the signal, having already been time division multiplexed into high speed in electrical domain, is then multiplexed into even higher-speed signal in the optical domain. In a successful OTDM system, the bit rate of a single channel can achieve as high as a typical speed of 160Gb/s. This technology overcomes the electrical bottlenecks, thus is an effective way to improve the capacity of the optical fiber transmission. Here, with the support of the "Huawei Technology Fund", the 160Gb/s OTDM systems and their transmission performance are studied comprehensively and profoundly. The main achievements and conclusions are summarized as follows.(1) Previous researches on the high-speed OTDM systems are surveyed. Details of schemes and theories are analyzed and summarized comprehensively for the key steps of the technology, which includes the generating of ultra-short pulses, the compression of pulses, the optical clock extraction, the optical time devision de-multiplexing, and so on. Furthermore, experimental and practical schemes for 160Gb/s OTDM systems are given.(2) The transmission performance of the 160Gb/s OTDM systems are profoundly studied. OTDM transmission systems are simulated with MATLAB and Optisystem3.1. Main Factors which play important roles in 160Gb/s OTDM transmission are studied, including residual dispersion, nonlinear effect, noise from the amplifiers, polarization mode dispersion (PMD). Furthermore, the principles of optimizing the OTDM transmission lines are given.(3) RZ-OOK, RZ-DPSK and RZ-DQPSK are introduced as the three promising modulation formats for 160Gb/s systems; three fiber-combinations among commercial fibers are found out to be suitable for 160Gb/s OTDM transmission. Based on the work mentioned above, transmission schemes with the three formats and the three fiber-combinations are designed and compared. Then, for 160Gb/s OTDM transimission systems, the most suitable fiber combination and the format of the best transmission performance are concluded.