Full-Duplex Relay Interference Cancellation via Channel Estimation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional relay station technologies face limitations in full-duplex operation due to interference between transmit and receive signals, leading to resource wastage and reduced system capacity, especially in MIMO systems where inter-antenna interference complicates interference channel estimation and synchronization.
Innovation Solution
An apparatus and method for interference cancellation and synchronization maintenance in a full-duplex relay system, employing an interference channel estimator, interference signal controller, and synchronization unit to estimate and cancel interference signals, allowing stable synchronization tracking and data storage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If full-duplex relay method is used to enable transmission and reception using same resources, then system capacity and resource allocation flexibility are improved, but interference between transmitted and received signals deteriorates reception quality
Solution Approach 1:
The patent converts the harmful self-interference signal into a useful component for channel estimation. By treating the transmitted signal as a pilot signal, the system estimates the interference channel and subtracts it from the received signal, transforming the interference from a detrimental factor into a resource for system operation.
Solution Approach 2:
The patent extracts the interference component from the received signal through channel estimation and signal subtraction. The interference channel is estimated separately, and the corresponding interference signal is extracted and removed from the composite received signal, leaving the desired signal for processing.
2Adaptability or versatility
If interference cancellation is performed to enable full-duplex operation, then resource utilization is improved, but synchronization performance deteriorates due to interference
Solution Approach 1:
The patent performs preliminary synchronization before interference cancellation. The synchronization process is executed on the received signal before the interference subtraction step, ensuring that synchronization algorithms can operate on the full-strength signal including interference, rather than on the processed signal where interference has already been removed.
Solution Approach 2:
The patent segments the processing into distinct stages: first synchronization is performed on the raw received signal, then interference cancellation is applied to the synchronized signal. This segmentation allows each process to operate optimally without interfering with the other.
3Productivity
If MIMO system uses multiple antennas for transmission and reception, then data rate is improved, but inter-antenna interference complicates channel estimation
Solution Approach 1:
The patent introduces an interference channel estimator as an intermediary component that specifically estimates the self-interference channel in MIMO full-duplex systems. This estimator acts as a mediator between the transmitted and received signals, characterizing the interference path so that it can be compensated for in the data detection process.
Data Source
AI summary
An apparatus and method for interference cancellation and synchronization maintenance over interference channel estimation in a communication system are provided. An interference channel estimator fixes synchronization and estimates an interference signal. An interference signal controller eliminates the estimated interference signal from a received RF signal. A synchronization unit unfixes fixed synchronization and tracks synchronization when the interference signal cancellation is stable. A data buffer stores data from which the interference signal is canceled.