| Optical transmission of digital multi-level QAM and analog AM-VSB television signals is of interest to both the telecommunication and CATV industries. This fiber-optic video signal transport scheme has the advantages of compatibility with the existing CATV network and of channel capacity sufficient to meet anticipated future requirements for compressed digital video signals.;This thesis contains a comprehensive study of the performance of a hybrid AM-VSB/QAM optical transmission system based on theoretical analysis and laboratory measurements, with particular emphasis on determining the impact of noise and nonlinear distortion on the bit error rate (BER) performance of the QAM signals.;The random nature of nonlinear distortion products within a 10 MHz bandwidth is investigated. By combining a theoretical BER analysis employing Middleton's Class A noise model and experiments, we verify the impact of non-Gaussian impulsive noise on the BER performance of a 64-QAM signal in a hybrid AM-VSB/QAM optical fiber transmission system. The specific parameters that are evaluated experimentally and theoretically are the modulation index, signal to noise ratio (SNR), and signal to nonlinear distortion ratio (SNLD). In addition, the performance degradation due to the interaction between fiber dispersion and Erbium Doped Fiber Amplifier's non-flat gain spectrum is discussed.;Finally, a channel capacity study based on the experimental measurements is presented in order to show the feasibility of simultaneous transmission of digital and analog video signals over optical fiber. |
