Two-step resource sharing and uplink power control optimization in LTE-Advanced relay networks

Relay enhanced networks are expected to fulfill the demanding coverage and capacity requirements in a cost-efficient way. Type 1 inband relaying is now being standardized as an integral part of 3GPP LTE-Advanced. This type of relay nodes supports a relaying mode where the relay link transmission is time-division multiplexed with the access link transmission, whereas macro users share the same resources with the relays. Hence, system performance depends strongly on the resource sharing strategy among and within the links. Besides, in order to fully exploit the benefits of relaying, the inter-cell interference, which is increased due to the presence of relay nodes, should be limited via a proper power control scheme on each link. Therefore, an optimization of both the resource sharing and power control strategy is required to enhance the overall performance of relay networks. In this paper, performance evaluation of two-step resource sharing and power control optimization is carried out within the LTE-Advanced uplink framework in urban and suburban scenarios. Furthermore, we propose a combination of scheduling based on the number of relay-served users and throughput throttling achieving max-min fairness. Results show that the proposed scheme achieves significant throughput gains and high system fairness.