Highly linear lightwave video distribution system

Television has become the primary information source for people in modern society. Nowadays, new and versatile services are emerging into cable TV service. With its extremely wide bandwidth and low loss, distribution systems which based on fiber-optic technology become the logical choice for future video distribution networks to provide the new service. Lightwave components have their own characteristics that are quite different from their electronic counterparts. There is an acute need to understand the basic characteristics of lightwave components and fully utilize their potential capabilities. This thesis provides such a framework.; Three major specifications for cable TV distribution are carrier-to-noise ratio (CNR), composite-second-order (CSO) and composite-triple-beat (CTB). Typical requirements are CNR = 52 dB, CSO = {dollar}-{dollar}65 dBc and CTB = {dollar}-{dollar}65 dBc. Currently, very few transmitters meet the stringent linearity requirements. In this thesis, we propose and demonstrate two linearization schemes to meet the linearity requirements; one is frequency planning (FP) and the other is predistortion. Experimental results show a 15 dB improvements in CTB for a 60-channel system by using EP. A linearized external modulator (LEM) using predistortion technique is presented and analyzed. Experimental results show that CTB and CSO values of less than {dollar}-{dollar}65 dBc can be achieved with this LEM.; Recently, fiber amplifiers have gained substantial attention. A distortion model for erbium-doped fiber amplifier (EDFA) is proposed. The model agrees very well with experimental data in predicting the slope of second and third order distortion frequency-dependence. EDFA's CNR is analyzed and optimized for three different parameters: (1) operating point, (2) amplifier's fan-out and (3) erbium fiber length.; We further consider system level impairments, such as the reflection-induced noise, stimulated Brillouin scattering and laser frequency chirp-induced distortion. Experimental results are given to show the degradations from these impairments. Finally we consider system architectures for lightwave distribution systems using EDFA. The objective for the system study is to provide system designers with some options and considerations in choosing transmitters and system architectures under specific system requirements. Through these analyses and optimization process, a highly linear lightwave video distribution system can be realized.