Fallback DCI Scrambling Initialization for RRC Reconfiguration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In wireless communication systems, existing technologies face challenges in efficiently handling periods of ambiguity or uncertainty during Radio Resource Control (RRC) reconfiguration, particularly in scheduling data and reference signals using fallback Downlink Control Information (DCI) formats, which lack configurability and flexibility.
Innovation Solution
The method involves initializing a sequence for scrambling data and reference signals using a configurable parameter, either specific to a User Equipment (UE) or a cell ID, depending on the DCI format and search space, allowing for flexible scrambling in UE-specific and common search spaces, thus enhancing handling of RRC reconfiguration periods.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If fallback DCI formats are used for scheduling during RRC reconfiguration, then reliability of communication is maintained, but flexibility and configurability are reduced
Solution Approach 1:
The patent introduces dynamic selection between different DCI formats (fallback and non-fallback) based on the search space type and RRC state. The UE and network can adaptively choose appropriate DCI formats during RRC reconfiguration, transitioning from static fallback usage to dynamic format selection, thereby maintaining reliability while improving flexibility.
Solution Approach 2:
The patent changes the parameter of DCI format configurability by introducing different initialization behaviors for scrambling sequences based on DCI format type. For fallback DCI, a default cell ID is used; for non-fallback DCI, a configurable parameter can be used. This parameter change enables flexible adaptation during RRC reconfiguration while maintaining communication reliability.
2Adaptability or versatility
If configurable parameters are used for sequence initialization in UE-specific search space, then flexibility is improved, but device complexity increases
Solution Approach 1:
The patent applies different scrambling initialization methods to different search spaces: UE-specific search space uses configurable parameters for flexibility, while common search space uses default cell ID for simplicity. This local differentiation optimizes the balance between flexibility and complexity for each search space type independently.
Solution Approach 2:
The patent segments the DCI processing into different paths based on search space type and DCI format. The UE separately handles fallback DCI (using default cell ID) and non-fallback DCI (using configurable parameter), reducing overall processing complexity by dividing the problem into manageable segments with different complexity levels.
3Device complexity
If default cell ID is used for all DCI formats, then device complexity is reduced, but adaptability for different search spaces is limited
Solution Approach 1:
The patent introduces dynamic selection of scrambling initialization parameters based on the DCI format type and search space. Instead of always using the default cell ID, the system dynamically switches between default cell ID (for fallback DCI) and configurable parameters (for non-fallback DCI in UE-specific search space), achieving adaptability without excessive complexity.
Solution Approach 2:
The patent changes the scrambling initialization parameter from a fixed default cell ID to a configurable parameter when appropriate conditions are met (non-fallback DCI in UE-specific search space). This parameter change enables search space-specific configurability while maintaining simplicity through conditional application.
Data Source
AI summary
A base station may transmit downlink control information (DCI) scheduling communications between the base station and a UE. The DCI is in a fallback DCI format. Based on whether or not the DCI is in a UE specific search space with cyclic redundancy check (CRC) scrambled by a UE ID of the UE, data transmitted by the base station or by the UE according to the DCI may be scrambled by a sequence that is initialized with a configurable parameter, or initialized with a cell ID.