Abstract:

Abstract: In OFDM-based cooperative two-way relay networks, sum rate and fairness among user pairs cannot
be achieved simultaneously when these user-pairs exchange their information respectively via an amplify-andforward two-way relay. This paper proposes a novel suboptimal resource allocation scheme to trade off the
proportional fairness and the system sum rate. This scheme is divided into two steps to maximize the sum rate
of the system subject to the constraints of total power and proportionality among user-pair data rate. First,
sub-carrier optimization is processed with equal power among every subcarrier to achieve proportional fairness
and improve the system sum rate. To further improve the sum rate while maintaining fairness, the total power
is allocated to every sub-carrier with an iterative power allocation algorithm. Simulation demonstrates that
the proposed scheme of resource allocation can achieve good tradeoff between proportional fairness and system sum rate.
Keywords:

Key words: OFDM, two-way relaying, proportional fairness, sub-carrier optimization, power optimization