EPDCCH Resource Mapping for HARQ Feedback Capacity

The downlink control channel is divided into multiple downlink control channel sets, each set containing multiple resource block pairs. The uplink control channel resources are then mapped to these sets in a segmented manner, where each set has its own starting offset indication. This segmentation allows the system to manage the complexity by breaking down the resource mapping into smaller, more manageable units while still achieving increased system capacity through the introduction of EPDCCH.

Instead of transmitting complete resource allocation information for all downlink control channel sets, the system transmits only the starting offset indication for each set. This partial information approach is sufficient for the UE to determine the appropriate uplink control channel resources, thereby increasing downlink control channel capacity while minimizing the overhead of resource allocation information transmission.

The starting offset indication information is transmitted in advance as part of the downlink control channel set configuration. This preliminary provision of resource indication information allows the UE to efficiently determine uplink control channel resources without performing complex real-time calculations, thereby improving HARQ ACK/NACK feedback efficiency while keeping device complexity manageable.