Multi-Antenna Interference Cancellation for Co-Channel Reception
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional wireless networking techniques, such as spatial reuse, often result in directional or geographical overlap between wireless networks, leading to co-channel interference where devices cannot receive feedback to reduce transmission power, causing impaired reception performance and reduced throughput due to unmitigated interference from adjacent networks.
Innovation Solution
Implementing an interference canceller in multi-antenna receivers that determines an interference cancellation matrix to remove interference from received signals, improving receive performance by estimating and canceling both portions of interference using frequency domain processing and channel estimation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If spatial reuse is implemented to increase spectrum efficiency, then network throughput is improved, but co-channel interference increases causing degraded reception performance
Solution Approach 1:
The patent converts the harmful interference into a useful signal by having the interfering transmitter send null data packets (NDPs) that can be processed to extract interference channel state information. This transforms the previously harmful interfering transmissions into a resource for interference characterization and cancellation, allowing the receiver to improve throughput while maintaining reception performance despite spatial reuse operations.
Solution Approach 2:
The patent implements a feedback mechanism where the receiver measures interference channel state information from NDPs and feeds back interference cancellation matrices to the interfering transmitter. This enables the interfering transmitter to adjust its precoding matrices to steer nulls toward the victim receiver, dynamically reducing interference while maintaining spatial reuse benefits.
2Reliability
If interference cancellation processing is applied to remove interfering signals, then reception performance is improved, but device complexity increases
Solution Approach 1:
The patent performs interference cancellation in the frequency domain before OFDM demodulation and decoding operations. By removing interference early in the processing chain from the received frequency-domain signals, subsequent processing stages work with cleaner signals, reducing the overall computational burden and improving reliability without proportionally increasing complexity.
Solution Approach 2:
The patent divides the interference cancellation process into separate stages: first extracting interference channel state information from NDPs, then computing interference cancellation matrices, and finally applying these matrices to data packets. This segmentation allows each stage to be optimized independently and enables efficient implementation using existing OFDM processing infrastructure.
Data Source
AI summary
The present disclosure describes apparatuses and methods for interference cancellation in multi-antenna receivers. In some aspects, a packet transmitted through a wireless environment is received via multiple antennas of a receiver, the packet being affected by interference of the wireless environment. The receiver multiplies signals of the packet with an interference cancellation matrix to provide reduced-interference signals of the packet from which a first portion of the interference is removed. Based on a first set of the reduced-interference signals of the packet, the receiver provides a reduced-interference channel estimate. A second portion of the interference is then removed from a second set of the reduced-interference signals using the reduced interference channel estimate. By so doing, the receiver may reduce effects of interference of the wireless environment (e.g., interfering packets or signals) to improve receive performance (e.g., bit-error rate) for packets that are intended for reception by the receiver.