ABSTRACT
This chapter discusses Coded Orthogonal Frequency Division Multiplexing (COFDM). OFDM, the progenitor of COFDM has been around for quite a while. This modem version was first described in 1966 by the Bell Laboratories researcher who patented it, but an earlier scheme that was predictive of the concept goes all the way back to the days of the radiotelegraph. COFDM was first applied to broadcast applications in Europe as part of the work on Digital Audio Broadcasting (DAB). It was intended to provide a method for receiving digital terrestrial radio broadcasts in a moving car with only the typical vehicular monopole antenna. The chapter addresses another problem by the transmission method for DAB was the wide variations in signal level that occur in a moving automobile. Intra-symbol interference is another significant effect of echoes on recovery of data signals that is handled differently in OFDM than in single-carrier systems.
