Development of a Combinational Users Selection Scheme to Enhance Efficient Resources Allocation in a Femtocell

Abstract

Accessibility is one of the Key Performance Indicators (KPI) that is used by Long Term Evolution Mobile Networks to check on the quality of the services offered to mobile users. A number of techniques have been used to allocate resources to users. These methods have experienced challenges in terms of allocating multiple resources at high data rates due to the ever growing demands for mobile users within existing resources. This has prompted continuous research in optimization of resource allocation on the existing systems. Due to this, improving resource allocation techniques is a viable area of research in Orthogonal Frequency Division Multiple Access (OFDMA) networks. This is with reference to power levels, Signal to Interference plus Noise ratio (SINR) and limited resource availability to multiple users requesting for resources in a femtocell. A combinational resource allocation scheme is hereby presented in which the available resource blocks are taken into account alongside the users’ resource requests. Signal to Interference plus Noise Ratio computation is then done per user. In addition, all possible arrangements of all users are evaluated to determine the highest SINR levels hence, the best combination of users in comparison to resource requests to allocate the resource blocks at the femtocell. Fairness is also utilized in situations where low SINR valued users have been left out of the femtocell resource allocation. In this case, a resource is reallocated from the next lowest SINR valued user to the user who has been left out to enable the user to communicate. The proposed combinational algorithm is tested in four scenarios. The first scenario tests the algorithm in a femtocell where six users need to only connect and synchronize to the femtocell. In this case, only one resource is required per user and there are only four available resources. The algorithm prioritizes the users with high SINR values and allocates each one of them a resource. The second scenario considers six users who are requesting for more than one resource for data transmission. When the users are allocated resources, one user is found to be left out. The fairness scheme reallocates a resource to the user who is left out and ensures that all users communicate in the femtocell. The third scenario compares the Combinational technique with the Global mobility prediction technique using eight users requesting for resources at eight intervals. The tests conclude that the Combinational technique achieves higher SINR total values for users allocated and also, when incorporated with fairness, all the low SINR valued users are able to be allocated resources in the femtocell. Therefore, all users can communicate. Finally, the fourth scenario tests the effectiveness of fairness in ensuring that all users are allocated resources. It determines that all users are allocated at least a resource to communicate with just a small compromise on the SINR total value in the femtocell.