Evolution of Physical Downlink Control Channel ( PDCCH ) for LTE-Advanced Systems

Abstract

In progressive pattern, 3GPP has continued to expand and improve capacity of LTE data and control channels especially for downlink transmissions. Among others, the physical downlink control channel (PDCCH) was designated in 3GPP LTE release 8 for sending downlink control information (DCI) to user equipment (UE), The DCI message is needed by every UE within the network in order to be served or serviced. The PDCCH make use of limited resource within the control region to perform this function. These resources become scarcer as the number of UEs increase within the network. As such, the PDCCH design becomes crucial to meet continuously increasing demand for ever increasing data transmission. Different designs have led to evolution of PDCCH in stages to suit scenarios and also fit new technologies introduced for LTE- Advanced systems. This article explains the underlying principles of PDCCH and how it has evolved to conform to the requirements of LTE-Advanced system specifications. We also provide some research opening for future breakthrough for DCI messaging.