Resource Allocation And Performance Improvement On Mixed Traffice Senarios In LTE-A Network

Nowadays, although the data traffic and the data revenues are increasing, the voice service still contributes a considerable amount of the operators’ revenues. It still affects a lot on people’s daily lives. Since LTE system only supports packet services, the voice service will use Voice over LTE (VoLTE) other than Circuit Switched (CS) voice. Voice over IP (VoIP) applications such as Skype, Gtalk and Asterisk have become very popular on the Internet. As more and more LTE base stations are being deployed, VoLTE will replace the CS technology and become the main method for voice service.Voice of LTE (VoLTE) is used to support voice communications in LTE network. However, the main weakness point of VoLTE is that the sound quality is sometimes not desirable. What’s more, large number of VoLTE users will consume so many resource by conservative resource allocation schemes and the performance of other data services will be impacted consequently. In this paper, we evaluate the impact of VoLTE on the other data services in different scenarios. In addition, the improvement of the impact by using carrier aggregation is also be evaluated. Through the simulation results, it is obvious that finding an effective resource allocation algorithm to ensure not only the quality of voice service but also the performance of other data services is important. As one of the key techniques for VoLTE, semi-persistent scheduling (SPS) is important to improve the capacity of VoLTE users. However with SPS, the resource and modulation and coding scheme (MCS) are usually decided by the initial scheduling and keep unchanged during the active state. Considering the continuously changing channel, it is hard to ensure the performance of the voice packet. In order to solve this problem, a resource allocation algorithm is proposed based on the prediction of channel quality change. Furthermore, the data rate of Adaptive multi Rate(AMR) codec is adaptively adjusted in the resource allocation algorithm to reduce VoLTE’s impact on other data services. Simulation results prove that the proposed algorithm can reduce the retransmission of VoLTE users and improve the throughput performance of other traffic businesses.