| The increasing interest in modern multimedia applications, such as broadband Internet, HDTV, etc. requires new access techniques for connecting the private premises to a communication backbone. One promising technology, Broadband over Powerlines (BPL), uses electric powerlines as a high speed digital data channel to connect a group of private users to a very high data rate backbone, such as fiber optic. The lines in power delivery network can be categorized based on several criteria. Depending on line voltage, HV (high voltage), MV (medium voltage), and LV (low voltage) grids are typically defined. Most HV/MV transformers locations are equipped with a high-speed fiber connection. Therefore, MV lines can act as the first pipeline of high-speed connection from backbone to the home users.; In this dissertation, we explore the potential of this technology and then examine the system performance enhancement for such channel environment using different modulation and coding techniques.; Although for nearly a century some elementary transmission models of these lines have been available, no serious attempt has gone into a comprehensive BPL channel modeling for high frequency spectra. In this research we use a new modeling of multi-conductor wave propagation in overhead lines, considering transient effects. The model identifies independent wave modes for overhead lines and it is useable over a wide range of frequencies. The proposed model incorporates realistic ground admittance, appropriate for higher frequencies used by broadband over powerline communications. By calculating the lossy ground impedance for multi-conductor lines, we derive a transfer function for these networks. By applying water filling in spectral domain, we were able to express the channel capacity of powerline networks, using the developed transfer function. The powerline channel suffers from multipath fading and frequency selectivity. Nevertheless, the calculated channel capacity limit promises very high data rates over this channel.; Furthermore, LV powerline channels suffer from impulsive bursty noise. In this dissertation two models for this noise are presented and discussed. (Abstract shortened by UMI.)... |
