This paper designs a resource allocation to minimize the total transmit power of a multi-band wireless network under the required rate constraint. The required rate splitting scheme is proposed to reduce the computational complexity of the multi-band resource allocation. On the basis of the primal decomposition method, the multi-band resource allocation is decomposed into multiple sub-band resource allocations and the required rate splitting. Numerical results show that the performance gap between the proposed resource allocation and the optimal resource allocation is negligible. It is also observed that the proposed resource allocation provides better performances than the conventional resource allocation.
