EPDCCH Aggregation Level Ambiguity Resolution

The enhanced physical downlink control channel (EPDCCH) segments the control channel resources into enhanced control channel elements (ECCEs), which are further divided into enhanced resource element groups (EREGs). This segmentation allows for more granular resource allocation and resolves ambiguity by enabling specific aggregation levels to be assigned to different ECCE sets, thereby improving both capacity and decoding reliability.

The patent introduces a new dimension for control channel resource allocation by utilizing resource blocks (RBs) in the frequency-time domain for EPDCCH, rather than relying solely on the traditional time-frequency resources of PDCCH. This dimensional expansion allows for increased capacity and provides additional degrees of freedom for resolving aggregation level ambiguity through diverse resource mapping strategies.

The patent applies preliminary actions by pre-configuring aggregation level specific phase shifting, scrambling sequences, and interleaving patterns before EPDCCH transmission. These pre-defined processing parameters are associated with specific aggregation levels, allowing the receiver to efficiently decode by selecting the appropriate preprocessing parameters without requiring complex real-time analysis, thus managing device complexity while maintaining enhanced capacity.

The patent utilizes parameter changes by varying phase shifting values, scrambling sequences, and interleaving patterns based on the aggregation level. Each aggregation level is assigned specific parameter sets, allowing the system to differentiate between multiple EPDCCH transmissions with the same resource allocation. This parameter differentiation resolves ambiguity while enabling the system to fully utilize the resource block capacity.

The patent implements self-service mechanisms where the aggregation level specific processing parameters (phase shifting, scrambling, interleving) are designed to be self-identifiable at the receiver. The receiver can autonomously determine the correct aggregation level and corresponding processing parameters by detecting characteristics in the received signal, eliminating the need for extensive trial-and-error decoding. This self-identification capability maintains high decoding accuracy while minimizing processing time.

The patent replaces mechanical trial-and-error decoding approaches with a more efficient system based on pre-configured parameter sets. Instead of mechanically attempting multiple aggregation levels sequentially, the system uses substitutive methods where the correct aggregation level is identified through parameter matching, significantly reducing processing time while maintaining decoding accuracy through the use of aggregation level specific phase shifting, scrambling, and interleving.