Multi-Physical OFDM Structure for Mixed Subcarrier Spacing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing wireless communication systems face challenges in improving communication flexibility and efficiency, particularly in accommodating low complexity and bandwidth-reduced user equipment (UEs) such as Machine-Type Communications (MTC) devices, which require enhanced coverage and low power consumption, and in managing radio resource utilization in carrier aggregation and dual connectivity scenarios.
Innovation Solution
The system employs a method for aligning the starting or ending positions of OFDM symbols with different cyclic prefix lengths across subcarriers to optimize resource element mapping, using integer multiples or sub-multiples of subcarrier spacing, and aligning these positions at slot or resource block boundaries to enhance communication efficiency and accommodate diverse UE categories, including low complexity and bandwidth-reduced devices.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If multiple connections are used for wireless communication, then communication capacity and speed are improved, but system complexity and resource overhead increase
Solution Approach 1:
The patent segments the uplink transmission by dividing it into multiple independent SCS configurations (first SCS and second SCS). Each SCS operates as a separate transmission path with its own resource allocation, allowing the system to achieve high communication capacity through parallel transmissions while managing complexity by treating each segment independently rather than as a monolithic system.
2Adaptability or versatility
If different cyclic prefix lengths are used for different subcarriers, then communication flexibility is improved, but resource element mapping complexity increases
Solution Approach 1:
The patent applies local quality by assigning different cyclic prefix lengths (first CP length for first SCS, second CP length for second SCS) to different subcarrier sets based on their specific requirements. This allows each local region (SCS configuration) to have optimized properties for its specific use case while maintaining overall system flexibility, without requiring a completely complex unified mapping solution.
Solution Approach 2:
The patent resolves the mapping complexity by introducing a new dimension - the SCS configuration dimension. Instead of trying to map different CP lengths directly onto the traditional time-frequency grid in a complex manner, the system creates separate resource element mappings for each SCS configuration, effectively adding a configuration layer that simplifies the overall mapping problem.
3Use of energy by moving object
If bandwidth-reduced UEs are supported, then power consumption is reduced, but communication coverage and reliability deteriorate
Solution Approach 1:
The patent employs parameter changes by introducing multiple SCS configurations (first SCS with first subcarrier spacing, second SCS with second subcarrier spacing) that can be selectively applied to different UE types. Bandwidth-reduced UEs can utilize the configuration optimized for their capabilities, achieving reliable communication coverage through appropriate parameter selection rather than through increased power consumption or bandwidth usage.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A method by a user equipment (UE) is described. The method includes receiving a first physical signal, determining a first physical structure based on information in the first physical signal, and determining resource elements based on the first physical structure. A first set of subcarriers with first subcarrier spacing which is integer multiple or integer submultiple of second subcarrier spacing are mapped such that in addition to a slot boundary one or more of starting positions or ending positions of first subcarriers with the first subcarrier spacing in a first set of OFDM symbols are aligned with one or more of starting positions or ending positions of second subcarriers with the second subcarrier spacing in a second set of OFDM symbols.