Cross-layer Resource Allocation In LTE-A System

With the development of wireless communication services, the demand of transmission rate, transmission delay in communication systems increases quickly. Cross-layer design becomes a research hotspot in recent years because of the advantages in improving the traditional network protocols and system performance. The cross-layer design combining with LTE-A system can effectively enhance system robustness and improve the overall efficiency of the system. Effective resource allocation scheme based on cross-layer design of the LTE-A system can further reduce the bit error rate and increase the system capacity.A simulation platform of LTE-A system is built using the OMNeT++ discrete event simulator and INET simulation framework. The PDCP, RLC, MAC and PHY layer of the protocol stack are implemented in LTE-A system. which is subject to the channel capacity constraints. The resource allocation in LTE-A system is studied and a subcarrier allocation scheme is proposed on the Cuckoo Search algorithm, considering the transmission rate and transmission delay as the optimization objective. The improved Cuckoo Search algorithm is used in simulation under the same conditions, the validity and benefit of the improved algorithm are proved.The subcarrier allocation model of LTE-A system is analyzed to achieve the optimal subcarrier allocation scheme. Simulation results indicate that under the same conditions, the proposed subcarrier allocation scheme can increase the transmission rate effectively and satisfy the user's QoS requirements better. The average transmission delay is reduced of 3.1% to 3.9%, and the average loss rate of the system decreased 3.2% to 3.8 %.