Study of Optical OFDM Transmission in UWB-Over-Fiber WDM-PON Access Networks

The requirement of transmission data rates is more increasing for wireless communication system in recent years. The Ultra-wideband (UWB) communication technique and system owned the large bandwidth can utilized, high transmission rates and low power consumption, it being the center of attraction for new age wireless communication technique. This project mainly uses a novel time frequency code (TFC) scheme for a bidirectional multiband orthogonal frequency division multiplexing (MB-OFDM) ultra-wideband (UWB) wavelength division multiplexing-passive optical network (WDM-PON) access network. The scheme can provide high spectral efficiency, high-speed data transmission and avoid wireless multipath interference for the multi-user UWB wireless systems. First, The MB-OFDM signal applied on the UWB channel radio-over-fiber system is analyzed in theory to evaluate the signal amplitude and phase distortion. Here we propose a new pre-compensate method to reduce the radio frequency (RF) power attenuation. Moreover, the WDM-PON ring access network can avoid the interference by utilizing different time frequency code (TFC) under bidirectional transmission for upstream and downstream in the same wavelength. Vertical cavity surface emitting laser diode (VCSEL) and multi mode fibers are adopted in the access ring due to cost down and increase number of optical network units (ONUs). Furthermore, the simulation using Matlab software to generate MB-OFDM UWB signals can achieve the system performance under various channel models. The simulated result shows that the fixed frequency interleaving multiple TFC scheme can avoid the interference of the multiuser for high-speed wireless transmission. Finally, we set up an experimental MB-OFDM system to measure the spectrum, error vector magnitude (EVM), bit error rate (BER),..,etc and to demonstrate the feasibility of the proposed MB-OFDM UWBWDM-PON access network.

Project ID:PB10001-0993
External Project ID:NSC99-2221-E182-021-MY3