FDD TDD Cell Aggregation HARQ-ACK Timing
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Solution Overview
Problem
Current wireless communication systems face challenges in efficiently aggregating Frequency Division Duplexing (FDD) and Time Division Duplexing (TDD) cells, particularly in scheduling and transmitting control information and HARQ-ACK signals across different duplexing configurations, which affects radio interface efficiency and spectrum allocation.
Innovation Solution
A method is introduced where a base station and user equipment (UE) communicate using a Primary Cell (PCell) with Time Division Duplexing (TDD) and a Secondary Cell (SCell) with Frequency Division Duplexing (FDD), enabling the transmission of configuration information and control channels. The UE receives and transmits HARQ-ACK signals based on specific DCI formats, with adaptations for different duplexing configurations to optimize HARQ process management and resource allocation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If FDD and TDD cells are aggregated to increase capacity, then spectrum utilization and data traffic handling are improved, but control information transmission and HARQ-ACK signaling become more complex
Solution Approach 1:
The patent segments the control information transmission by separating FDD and TDD cell configurations into distinct parameters. The eNodeB transmits separate configuration information for FDD SCell and TDD SCell, including separate PDCCH configurations, DCI formats, and HARQ-ACK timing parameters. This segmentation allows each cell type to be managed with its specific characteristics while being aggregated for overall capacity enhancement.
Solution Approach 2:
The patent applies local quality by tailoring control information parameters specific to each cell type. For FDD cells, the patent uses FDD-specific DCI formats and HARQ timing, while TDD cells use TDD-specific parameters including UL-DL configuration indicators. This allows optimized control signaling for each cell type's specific operational characteristics.
2Loss of time
If HARQ process management is optimized across FDD and TDD cells, then latency is reduced, but the complexity of scheduling and transmitting control information increases
Solution Approach 1:
The patent segments HARQ process management by maintaining separate HARQ-ACK timing mechanisms for FDD and TDD cells. The eNodeB transmits separate configuration information including FDD HARQ-ACK timing parameters and TDD HARQ-ACK timing parameters, allowing independent optimization of HARQ processes for each cell type while managing overall scheduling complexity through structured parameter separation.
3Measurement precision
If DCI formats are adapted for different duplexing configurations, then control information accuracy is improved, but the complexity of transmitting and processing control information increases
Solution Approach 1:
The patent applies local quality by defining cell-specific DCI formats with tailored parameters for FDD and TDD configurations. The patent specifies separate DCI format parameters including FDD-specific fields and TDD-specific fields (such as UL-DL configuration indicators), ensuring accurate control information transmission for each cell type while managing processing complexity through standardized parameter sets.
Solution Approach 2:
The patent changes parameters by modifying DCI format structures according to cell type. The eNodeB transmits configuration information that includes different parameter sets for FDD SCell versus TDD SCell, with specific parameter changes such as different HARQ-ACK timing parameters, different PDCCH configurations, and cell-type-specific fields in the DCI formats.
Data Source
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AI summary
Methods and apparatus of a base station or a User Equipment (UE) in communication with each other are provided. The UE is configured by the base station for simultaneous communication with at least a cell using Frequency Division Duplexing (FDD) and at least a cell using Time Division Duplexing (TDD). Processes enabling transmission of control information associated with scheduling data reception or data transmission from the UE are provided.