Adaptation of Modulation and Coding for OFDM Packet Transmission
A novel protocol is proposed for adaptive modulation and coding for Orthogonal Frequency Division Multiplexing (OFDM) in packet radio networks. Previous protocols in the literature rely on channel measurements or parameter estimates to provide channel state information, which is then processed to determine the appropriate transmission parameters. The authors' proposed protocols avoid the complexity of making measurements or estimates; instead, they use simple statistics that are derived easily from the receiver's demodulator and decoder. Employing only these simple statistics from the reception of the most recent packet, their protocol first determines the code rate for the next packet and then selects the modulation format to be used on each subcarrier.