Coded Orthogonal Frequency Division Multiplex(COFDM) is a modulation technique based on Orthogonal Frequency Division Multiplex(OFDM) wich uses orthogonal sub-carriers to modulate the signal, differing on the adition of codification, wich adds the “C” to OFDM. The COFDM is the most used modulation, actually, to the existing TV Digital standards, the Digital Video Broadcasting (DVB) and the Integrated Services Digital Broadcasting (ISDB). The purpose of this paper is to show the functioning philosophy of such modulation, compair COFDM to the 8-Vestigial Side Band (VSB), wich is the modulation used on the standard Advanced Television System Comitee (ATSC), possible advantages and disadvantages of COFDM system, as well, intends to show that COFDM is the ideal for Digital TV, since it has the robustness necessary for many applications on Digital TV correctly works.
Ana Luiza Rodrigues
Regina Missias Gomes