Full Duplex Self-Interference Cancellation via Signal Segmentation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional wireless full duplex technologies face inefficiencies in eliminating self-interference signals in multi-antenna systems, particularly in wireless communication systems like LTE or UMTS, where the power difference between transmit and receive signals can be up to 80 dB to 140 dB, leading to interference that cannot be effectively canceled.
Innovation Solution
The method involves dividing self-interference signals based on power and delay characteristics into distinct components, such as main-path, near-zone reflection, and far-zone reflection signals, and performing sequential interference cancellation processing using reference signals to eliminate each component, improving suppression efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If conventional wireless full duplex technology is used to cancel self-interference signals, then transmission and reception can be performed simultaneously on the same wireless channel, but interference suppression efficiency is not high and the transmit signal cannot be effectively eliminated from the received signal
Solution Approach 1:
The patent segments the self-interference signal into multiple components based on power and delay characteristics: strong self-interference signals (with power above threshold and delay below threshold) and weak self-interference signals (with power below threshold or delay above threshold). This segmentation allows different cancellation strategies to be applied to different signal components, improving overall cancellation efficiency while enabling simultaneous transmission and reception.
2Productivity
If a base station uses multiple transmit and receive antennas in a MIMO system, then communication capacity is increased, but the power difference between transmit and receive signals becomes up to 80 dB to 140 dB making interference cancellation difficult
Solution Approach 1:
The patent applies local quality by treating different self-interference signal components with different characteristics. Strong self-interference signals undergo one type of cancellation processing while weak self-interference signals undergo another type, allowing the system to handle the extreme power differences (80-140 dB) in MIMO systems effectively while maintaining high communication capacity.
3Object-affected harmful factors
If single transmit antenna or part of transmit antennas self-interference cancellation is performed, then some interference can be reduced, but interference suppression efficiency remains low and cannot handle full duplex multi-antenna systems
Solution Approach 1:
The patent creates a universal interference cancellation method that works for both single-antenna and multi-antenna full duplex systems. By classifying self-interference signals into strong and weak components based on power and delay thresholds, the system can handle various antenna configurations and propagation environments, making the solution adaptable to different MIMO system scenarios.
Data Source
Figure 1~2
Figure 3
Figure 4
AI summary
Embodiments of the present invention provide a method, an apparatus, and a system for processing an interference signal, so as to eliminate an interference signal in a full duplex multi-antenna system. The method includes: receiving a radio signal, where the signal includes a self-interference signal of a transmit antenna, and the self-interference signal includes a first self-interference signal, and a second self-interference signal; performing primary interference cancellation processing, by using a first reference signal, on the received signal to eliminate the first self-interference signal; and performing secondary interference cancellation processing, by using a second reference signal, on the signal after the primary interference cancellation processing to eliminate the second self-interference signal.