UE MCS Table Selection for Flexible DCI and TB Size Determination
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current wireless communication systems lack flexibility and efficiency in supporting multiple service types, particularly in fifth-generation cellular systems, such as eMBB, URLLC, and mMTC, limiting communication reliability and efficiency.
Innovation Solution
Implementing a method and apparatus that utilize RRC parameters to determine modulation order and target code rate based on DCI fields other than the MCS field, enhancing the determination of transport block size for initial and retransmission scenarios, and aligning DCI sizes for efficient resource utilization.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a fixed MCS field size is used in DCI formats, then the DCI structure is simple and easy to decode, but the system lacks flexibility in supporting multiple service types with different reliability requirements
Solution Approach 1:
The patent applies dynamics by making the MCS field size variable rather than fixed. The MCS field can be 4, 5, 6, or 8 bits depending on the service type and reliability requirements. This dynamic adjustment allows the DCI structure to adapt to different service scenarios (eMBB, URLLC, mMTC) while maintaining a relatively simple base structure, thus improving versatility without excessive complexity increase
Solution Approach 2:
The patent changes the parameter of MCS field size from a fixed value to a variable parameter that can take different values (4-8 bits). This parameter change enables the system to flexibly support multiple service types with different reliability requirements. The base station can select appropriate MCS field sizes based on service type, thereby achieving adaptability while controlling overall system complexity
2Productivity
If variable bit MCS field is implemented to support multiple services, then communication flexibility improves, but the complexity of determining transport block size and aligning DCI sizes increases
Solution Approach 1:
The patent applies preliminary action by pre-defining multiple MCS index tables (first MCS index table, second MCS index table, third MCS index table) with different modulation orders and code rate ranges. These tables are prepared in advance and selected based on service type and reliability requirements. This preliminary preparation simplifies the real-time determination process, as the terminal only needs to select from pre-defined tables rather than calculate from scratch, thereby improving communication efficiency while managing complexity
Solution Approach 2:
The patent segments the MCS parameter space by dividing it into multiple discrete MCS index tables, each serving specific service scenarios. The first table serves general cases, the second table serves high-reliability cases, and the third table serves low-latency cases. This segmentation allows independent optimization for different service types and simplifies the determination process by limiting the search space to relevant segments only
3Reliability
If different MCS index tables are used for different service types, then communication reliability improves, but the complexity of MCS field interpretation and DCI processing increases
Solution Approach 1:
The patent introduces an intermediary mechanism - the New Data Indicator (NDI) field - to select between different MCS index tables. Instead of directly interpreting the MCS field differently for each service type, the NDI field acts as a mediator that indicates which MCS table to use. This intermediary approach simplifies the interpretation process by providing a clear selection mechanism, thereby improving reliability while managing the complexity of handling multiple MCS tables
Data Source
AI summary
A method by a user equipment (UE) is described. The method includes receiving, from a base station, a first radio resource control (RRC) parameter, monitoring a physical downlink control channel (PDCCH) with a first DCI format, receiving a transport block (TB) in a physical downlink shared channel (PDSCH) scheduled by the PDCCH with the first DCI format, wherein the first RRC parameter contains one or more MCS entries, each entry provides a modulation order and a target code rate, determining a modulation order and a target code rate used for the TB in the PDSCH at least based on a modulation code scheme (MCS) field and one, a part, or all of a plurality of specified DCI fields other than the MCS field.