Performance of separated random user scheduling (SRUS) and jount user scheduling (JUS) in the long - term Evolution - Advanced

Carrier aggregation (CA) is one of the main feature s in Long Term Evolution‐ Advanced (LTE-A). CA will allow the target peak data rates in excess of 1 Gbps in the downlink and 500 Mbps in the uplink t o be achieved and the users can have access to the total bandwidth of up to 100 MHz. The system bandwidth may be continuous or system consisting of several p arts of non-continuous aggregated bandwidth. This paper provides a summary of the supported CA scenarios as well as an overview of the advanced functionality of CA-LTE with particular emphasis on the basic concept, control mechanisms, and the performance aspects of (CA). This paper also demonstrates how CA can be used as an enabler for simple yet effective frequency domain interference management schemes. In particular, the interference management is to provide the intervention made sign ificant gains in heterogeneous networks, envisionin g intrinsically uncoordinated deployments from the ho me base stations. Then, we compared the quality of service (QoS) performances of two different multi-u ser scheduling schemes in CA based LTE-A systems, separated random user scheduling (SRUS) and joint user scheduling (JUS). The former is simpler but les s efficient, whereas the latter is optimal but with h igher overheadsignaling. Moreover, only one single component carrier (CC) is required to access for us er equipment (UE) in the case of SRUS, while all th e CCs must be connected in the case of JUS. Some technical challenges for implementing carrier schedulin g schemes technique in LTE-A systems, are discussed and highlighted.