Scattered search space scheme for PDCCH and ePDCCH in LTE-advanced

The Physical Downlink Control Channel (PDCCH) in the LTE system could not support the new features introduced in the LTE-Advanced system such as Coordinated Multipoint (CoMP), and Inter-Cell Interference Coordination (ICIC). Thus, enhanced Physical Downlink Control Channel (ePDCCH) evolved in LTE-Advanced to fulfill the new requirements and avoid the PDCCH problems. But one problem remained unsolved which is the low throughput due to the high blocking probability of the search space allocation scheme. This paper shows a scattered scheme for search space allocation to reduce the blocking probability and offer more throughput in the control channels PDCCH or ePDCCH. The scheme pivots on the idea of scattering the PDCCH candidates to be allocated in a non-contiguous manner. Simulation results showed a remarkable improvement in the blocking probability. The decrease in the blocking probability achieved by the proposed scheme will affect the total throughput of the system as control channels have a direct impact on data transmission and reception throughput.