Although various carrier aggregation deployment scenarios (CADSs) have been introduced in the LTE-Advanced system, issues related to insufficient eNB coverage that leads to low throughput and high drop call have yet to be solved. This paper proposes a new deployment scenario called coordinated contiguous-CADS (CC-CADS), which utilizes two-component carriers (CCs) that operate on two frequencies located in a contiguous band. Each CC antenna is directed to a cell boundary of the other CC. The handover performance of users with various mobility speeds under CC-CADS has been investigated and compared with various deployment scenarios proposed by 3GPP. Simulation results show that the received signal reference power (RSRP) enhancement and performed handover, ping-pong, drop call, and outage probabilities reductions in CC-CADS outperformed the 3GPP’s CADSs, thus leading to reduced interruption time, improved spectral efficiency, and seamless handover. 1. Introduction In the recent 3GPP LTE-Advanced releases 10 and 11 (Rels. 10 and 11), five carrier aggregation deployment scenarios (CADSs) were proposed [1–4] to provide sufficient coverage and enhance system performance to support user mobility within cells. Each CADS provides a different coverage area, which depends on the operating frequency bands and antenna orientation of the configured CCs. Therefore, each CADS provides different system performance results for users through its mobility within the cells. If carrier aggregation (CA) technology is considered, one of these scenarios should be carefully selected through a mobility study. Selecting the appropriate CADS must be built on an in-depth study to improve system performance during user mobility. Thus, this paper attempts to achieve this target. Few studies focus on system performance evaluation based on various CADSs in the LTE-Advanced system. In [5], the effect of CA on mobility was discussed over different CADSs in terms of handover delay, RSRP measurements, and handover trigger time used to trigger intra-LTE mobility when the neighbour becomes offset better than serving. In [6], a cell’s average throughput was evaluated based on two different CADSs through user mobility. In [7], the secondary cell measurement period was relaxed according to CADS to save user equipment (UE) power, thus reducing handover failure probability. In [8, 9], three handover methods were proposed in selected CADS to address conventional difficult handover scheme problems. However, previous research did not consider all handover performance metrics such as spectral
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