Subband Full-Duplex Interference Mitigation via Non-Contiguous CSI-RS
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In wireless networking, full-duplex communications face interference issues due to downlink transmissions from one gNB interfering with uplink transmissions of another gNB, and reference signals or channels overlapping with uplink transmissions, leading to suboptimal data rates.
Innovation Solution
The method involves characterizing and mitigating interference by using non-overlapping portions of Channel State Information reference signals (CSI-RS) for channel estimation and beam measurement, and generating differential CSI reports based on instructions from the network node to improve operation in full-duplex subband transmissions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If full-duplex communications are employed to improve data rates, then productivity is improved, but interference between downlink and uplink transmissions increases
Solution Approach 1:
The patent segments the frequency spectrum into subbands, allowing simultaneous downlink and uplink transmissions in different frequency portions. This segmentation enables full-duplex operation by spatially separating interfering signals in the frequency domain, thus improving data rates while managing interference between concurrent transmissions.
Solution Approach 2:
The patent applies local quality by assigning different transmission characteristics to different frequency subbands. Specifically, certain subbands are designated for downlink while others are for uplink, allowing each subband to have optimized quality characteristics for its specific direction, thereby enabling full-duplex operation with controlled interference.
2Measurement precision
If reference signals are transmitted to improve channel estimation accuracy, then measurement precision is improved, but overlap with uplink transmissions causes interference
Solution Approach 1:
The patent segments the frequency resources allocated to reference signals (CSI-RS) to avoid overlapping with uplink subbands. By configuring CSI-RS resources in specific frequency locations that do not coincide with uplink transmissions, the system maintains channel estimation accuracy while preventing interference with concurrent uplink data transmissions.
Solution Approach 2:
The patent introduces frequency domain coordination as an intermediary mechanism between downlink reference signal transmission and uplink data transmission. Through gNB configuration of CSI-RS resource locations, the system mediates potential conflicts by selecting frequency resources for reference signals that serve as intermediaries between the needs for accurate channel estimation and the need to avoid uplink interference.
Data Source
AI summary
A system and a method are disclosed for subband full-duplex. In some embodiments, a method includes: conducting a measurement, by a User Equipment (UE), using a CSI resource, the CSI resource being a Channel State Information reference signal (CSI-RS) or a Channel State Information Interference Measurement (CSI-IM); and performing channel estimation or beam measurement, by the UE, the channel estimation or beam measurement being based on a set of resources of the CSI resource, the resources of the set of resources being non-contiguous in a symbol of the CSI resource.