Downlink Control Signal Candidate Sets for Carrier Aggregation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current wireless communication systems face challenges in supporting carrier aggregation and coordinated multiple transmission and reception schemes while indicating quasi co-located assumptions between antenna ports, particularly in scenarios involving carrier aggregated scheduled elements and PDSCH RE mapping.
Innovation Solution
A method is proposed where a user equipment receives candidate sets of control information for carrier aggregation and coordinated multiple-point transmission and reception from a downlink serving base station, including indicators for quasi co-located antenna ports, channel state information-reference signal antenna ports, and PDSCH RE mapping information, allowing for efficient demodulation and decoding of downlink signals.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If carrier aggregation and coordinated multiple transmission and reception schemes are supported simultaneously, then system throughput and data capacity are improved, but control signal processing complexity and device complexity increase
Solution Approach 1:
The control information is segmented into multiple candidate sets, each corresponding to different transmission scenarios (carrier aggregation, coordinated multiple transmission and reception, or both). The user equipment only processes the relevant candidate set based on the indicated scenario, rather than processing all possible control information formats simultaneously. This segmentation reduces the overall processing complexity while maintaining support for multiple advanced transmission schemes.
Solution Approach 2:
The system dynamically indicates which candidate set of control information is applicable through a specific indicator field in the downlink control signal. This dynamic indication allows the user equipment to adapt its processing behavior in real-time based on the current transmission mode, optimizing the balance between supporting multiple transmission schemes and managing processing complexity.
2Measurement precision
If quasi co-located assumptions are indicated between antenna ports for carrier aggregated scheduled elements, then signal demodulation accuracy is improved, but control information overhead and device complexity increase
Solution Approach 1:
The quasi co-located assumption indication is extracted as a separate, dedicated field within the control information structure. Rather than embedding this information implicitly within existing control fields, the patent explicitly extracts and indicates the quasi co-located relationship between antenna ports through a specific indicator. This allows the user equipment to accurately determine demodulation references without requiring complex implicit derivations, improving demodulation accuracy while managing overhead efficiently.
3Adaptability or versatility
If multiple candidate sets of control information are provided for different transmission schemes, then adaptability and versatility are improved, but control signal complexity and processing time increase
Solution Approach 1:
Multiple candidate sets of control information are prepared in advance, each optimized for specific transmission scenarios (carrier aggregation only, coordinated multiple transmission and reception only, or both). By pre-configuring these candidate sets with appropriate formats and parameters for each scenario, the system enables the user equipment to quickly select and process the relevant candidate set based on the transmitted indicator, rather than needing to interpret and adapt control information in real-time for each possible scenario. This preliminary preparation reduces processing time while maintaining full adaptability.
Data Source
AI summary
A method by which a user equipment receives a downlink control signal in a wireless communication system supporting carrier aggregation (CA) and coordinated multiple-point transmission and reception (CoMP), according to one embodiment of the present invention, comprises the steps of: receiving candidate sets of control information for the CA and the CoMP from a downlink serving base stations; and receiving an indicator for indicating one of the candidate sets from the downlink serving base station, wherein the candidate sets of the control information comprise a usable set of control information with respect to each carrier wave, and the control information can include information on carrier waves scheduled by the downlink serving base station, information on channel state information-reference signal antenna port(s) that is (are) quasi co-located (QCL) assumable with demodulation-reference signal antenna port(s) of the downlink serving base station, information on PDCH resource element (RE) mapping and/or information indicating whether or not QCL assumption between the channel state information-reference signal antenna port(s) and antenna port(s) indicated by the information on PDSCH RE mapping is possible.