Free subcarrier optimization for peak-to-average power ratio minimization in OFDM systems

Peak-to-average power ratio (PAR) reduction techniques are often employed to increase the power efficiency of orthogonal frequency division multiplexing (OFDM) systems. A recently proposed PAR optimization method demonstrates how the PAR can be minimized when free subcarriers and a certain distortion allowance on the error vector magnitude (EVM) are available. In this paper, we derive the lower bound on the capacity for such a system and investigate the capacity- maximizing number of free subcarriers that should be used.