Análise de desempenho de um sistema de comunicação óptica que utiliza o método OFDM com detecção coerente

Abstract

In the last decades, society has witnessed a growing advancement of technologies and the telecommunications area is the most influenced by such advancement. The need to obtain information more quickly and easily drives the emergence of new devices that keep people increasingly connected to the world. In view of this demand to be always connected, it is necessary to study several methods of data transmission, in order to offer society increasingly efficient services. The use of optical systems has been growing in recent years, as they offer safer and faster data transmission, given the high speed of the light used in the transmission, as well as allowing a high rate of transmission over long distances, with fewer losses and errors. Optical fibers are more immune to electromagnetic interference, when compared to the transmissions via metallic cables and free space. Along with optical systems, it’s needed to apply some technique for the transmission to support multiple users in this system. Then, one technique that has proved to be efficient is Orthogonal Frequency Division Multiplexing (OFDM), which offers high rate transmissions over long distances and with high spectral efficiency. In the optical domain, OFDM with coherent detection (CO-OFDM) is used, which results in a more efficient data reception. In this context, this work performs a comprehensive study on the performance of the CO-OFDM system taking into consideration several system design parameters, such as: number of OFDM carriers, transmission rate, modulation formats, link distance and optical signal-noise ratio, among others.