Power allocation and control for coded OFDM wireless networks

A wireless cellular system employing orthogonal frequency division multiplexing (OFDM) is considered in this paper. Since cellular systems use frequency reuse concepts to enhance the area spectral efficiency, it introduces so called cochannel interference (CCI) which is one of the major sources of performance degradation. To mitigate the effect of CCI while satisfying required quality of service, the power level on each subchannel of OFDM systems should be allocated to and controlled at an optimum level. A conventional approach to OFDM power allocation system design is to maintain the same link quality for all subchannels. To overcome the drawbacks of the traditional approach, a new power allocation scheme exploiting the frequency diversity of OFDM systems by considering the error correcting coding is proposed. The frequency diversity is also exploited in the power control algorithm. Numerical results are presented to illustrate the advantages of the proposed algorithm over the conventional one