A novel cross-carrier scheduling method in carrier aggregation

Long Term Evolution (LTE) of Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access and Radio Access Network is a Fourth Generation (4G) wireless broadband technology which is capable of delivering high data transmission rates and low latency with reduced costs, among other promises. Carrier Aggregation (CA) is employed to improve the capacity of the cell. Regarding scheduling there are two main alternatives for CA, either resources are scheduled on the same carrier as the grant is received, or cross-carrier scheduling may be used. A key research topic is to design efficient and reliable Physical Downlink Control Channels (PDCCHs) that carry the downlink scheduling assignments and uplink scheduling grants. In Release11, the New Carrier Type characterized by no PDCCH was put forward which has to rely on the cross-carrier scheduling. However with the increase in carriers, CA-based HetNet with cross-carrier scheduling, in which case the PDCCH capacity might become a limiting factor. At the same time, the UE complexity for blind decoding is much higher than before. To solve the problems a novel cross-carrier scheduling method is proposed in this paper to reduce the PDCCH capacity blocking probability and UE complexity.