This paper proposes new scheme for efficient rate allocation in conjunction
with reducing peak-to-average power ratio (PAPR) in orthogonal
frequency-division multiplexing (OFDM) systems. Modification of the set
partitioning in hierarchical trees (SPIHT) image coder is proposed to generate
four different groups of bit-stream relative to its significances. The
significant bits, the sign bits, the set bits and the refinement bits are
transmitted in four different groups.