A Framework to Optimize the OFDM-Based Multiuser Dynamic Spectrum Access Networks with Frequency Reuse

This paper presents a novel framework to optimally solve the spectrum access problem at the central spectrum moderator (CSM) for multiple radio pairs. In the system model considered, the available spectrum is partitioned into N subcarriers, and the proposed CSM assigns subcarriers to multiple radio pairs with the objective to maximize the total achievable bit rate in the network. Each transceiver adopts the OFDM frontend, and transmits only on those subcarriers assigned to it. The proposed algorithm jointly considers the effect of interference from multiple co-channel radios, while at the same time supports all transmitters at their minimum guaranteed bit rate, under individual total transmit power constraint. Our proposed method converts the original NP-hard mixed integer non-linear programming problem into a mixed binary linear programming problem, which can be solved optimally using standard algorithms.