Adaptive bit and power loading for OFDM systems

An adaptive bit and power allocation algorithm for OFDM systems was proposed. Adaptive loading can improve the performance of broadband OFDM system because each individual subchannel has its own attenuation. The proposed algorithm allocates bits adaptively in the subchannels according to the subchannel gains to minimize the total transmission power for a given bit error rate. The algorithm can be used over multipath frequency selective fading channels for stable transmission speed. Results show that the proposed scheme can achieve considerable performance enhancement over non-adaptive systems.