Downlink Control Information Format for DMRS Interference Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In wireless communication systems, particularly in 3D MIMO, Massive MIMO, and virtual MIMO scenarios, the interference between Demodulation Reference Signals (DMRS) increases with the number of users and layers, affecting channel estimation and data demodulation accuracy.
Innovation Solution
The proposed solution involves an apparatus and method for processing downlink control information, which includes a downlink control information generation module that generates a format indicating the port and scrambling identity number for DMRS transmission, allowing for efficient allocation and reduction of interference by dispersing users across different ports and using distinct scrambling identity numbers.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If multiple users are multiplexed in 3D MIMO, Massive MIMO, or virtual MIMO scenarios, then the number of users and layers increases, but interference between DMRS accumulates and affects channel estimation accuracy
Solution Approach 1:
The patent segments the DMRS resources by assigning different port numbers and scrambling identity numbers to different users. This segmentation allows multiple users to share the same time-frequency resources while maintaining orthogonal or near-orthogonal pilot sequences, thereby reducing mutual interference and preserving channel estimation accuracy even as the number of multiplexed users increases
Solution Approach 2:
The patent introduces additional dimensions for DMRS differentiation beyond traditional single-user scenarios. By utilizing combinations of port numbers (vertical dimension) and scrambling identity numbers (horizontal dimension), the system creates a multi-dimensional DMRS resource space that can accommodate more users without increasing interference, thus resolving the contradiction between user multiplexing capacity and estimation precision
2Device complexity
If the same scrambling sequence is used by multiple users, then implementation is simplified, but significant interference occurs between users using the same scrambling code
Solution Approach 1:
The patent changes the parameters of the scrambling sequences by introducing scrambling identity numbers that differentiate users. Instead of using identical scrambling sequences, each user is assigned a unique combination of port number and scrambling identity number, which modifies the scrambling sequence parameters. This approach maintains relatively simple implementation while effectively reducing user-to-user interference through parameter differentiation
Data Source
AI summary
Disclosed are an apparatus and method for processing downlink control information, applicable to a base station and comprising a downlink control information generation module and a downlink control information transmission module, wherein, the downlink control information generation module is configured to generate a downlink control information format when data transmission is performed, wherein a field of the downlink control information format carries indication information for indicating to a terminal a port used for transmitting a data DMRS and a scrambling identity number corresponding to a pilot generation sequence; and the downlink control information transmission module is configured to transmit the downlink control information format to the terminal. By indicating to a terminal a port used for transmitting a data DMRS and a scrambling identity number corresponding to a pilot generation sequence, the embodiments of the present invention solve the problem of interference between DMRSs used during multi-user data transmission.