Optimal power allocation for OFDMA-based cooperative base stations by limiting interference

In this paper, the problem of maximizing the sum rate of two interfering users, while limiting the received interference at each user, in an OFDMA-based system operating in downlink is considered. In a cooperative two cell scenario, for each particular user (located in the edge of cooperative cell and within area common with neighboring cell), it is possible to incorporate the dominant interference effects of the neighboring cells within the received noise level. As applied to the scheme, the authors investigate a scenario where two cooperative cellular systems operate in the same band. We first consider a scenario where each user having only two sub-channels. Then, this approach is extended to a TV sub-channel scenario. Numerical results show that proposed cooperative BSs scheme outperforms compared with non-cooperative TDMA case and it can achieve excellent levels of efficiency by allocating resources more intelligently.