Research On Resource Allocation And Power Control Scheme In Heterogeneous Networks

With the increasing number of the communication system users and the increasing demand forhigh-speed data services, higher system capacity, larger coverage and better quality are required. Atthe same time, more and more mobile service occurs in the room, but the service of poor quality isexperienced due to the penetration loss.Femtocell, as an effective technology to improve indoor coverage, has been extensively studiedand researched. Embedding femtocell in macro-cellular network is a promising method forachieving substantial gains in coverage and capacity compared to macro-only networks. However,the random manner of deployment may cause higher interference magnitude and variability in theheterogeneous cellular network. Methods to solve the interference problem between the femtocelland marcocell in LTE-Advanced scenario can be generally divided into3categories: time domainadjustment, frequency domain coordination, and power control. Based on the study ofheterogeneous network interference coordination, some of the methods are analyzed in this thesis.Furthermore, optimized methods are proposed corresponding to each available method. Numericalsimulation shows that the interference is reduced and large gain is acquired using this method. Theworks of this thesis are as follows.Firstly, the concept and the key technologies of femtocell are introduced, and the interference inthe heterogeneous networking is analyzed.Secondly, some of the common frequency domain interference coordination techniques areexplained. Based on these methods, a self-adaptive spectrum resource allocation scheme isproposed. Numerical simulation shows that better user performance and larger system throughputare provided via this scheme.Finally, four power control schemes for femtocell are analyzed. Advantages and disadvantagesare compared among these schemes in terms of mitigating interference. An optimization paradigmis proposed, under the premise of ensuring the femtocell users performance and avoiding causingtoo much interference to marcocell users. Numerical simulation shows that this scheme is not onlyeasy to implement in practical engineering, but also improves the performance.