Preamble-Based Collision Detection for Full-Duplex WLANs
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Full-duplex (FD) wireless local area networks (WLANs) face challenges with self-interference (SI) and inefficient collision detection methods, particularly in prioritizing traffic and resolving collisions without complete Self-Interference Cancellation (SIC).
Innovation Solution
A preamble-based collision detection apparatus and method that uses orthogonal preambles to rapidly detect collisions without SI estimation, embedding priority information in preambles, and implementing a collision resolution estimation and scheduling mechanism for prioritized traffic.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If Full Duplex technology is used to increase spectral efficiency, then communication throughput is improved, but self-interference issues worsen
Solution Approach 1:
The patent extracts and removes the self-interference component from the received signal through self-interference cancellation techniques. The FD transceiver identifies and subtracts the transmitted signal's self-interference portion from the received signal, effectively taking out the harmful self-interference to enable clear full-duplex communication
Solution Approach 2:
The patent introduces an intermediary self-interference cancellation mechanism between the transmitted and received signals. This intermediary process processes the received signal by removing self-interference components, allowing the FD transceiver to simultaneously transmit and receive without the transmitted signal interfering with the received signal
2Reliability
If traditional collision detection methods are used in FD WLANs, then collision detection capability is maintained, but detection speed worsens due to SI estimation requirements
Solution Approach 1:
The patent applies preliminary action by performing self-interference cancellation before collision detection. By pre-processing the received signal to remove self-interference components, the system prepares the signal in advance, enabling faster and more accurate collision detection without having to perform SI estimation during the detection process itself
3Adaptability or versatility
If prioritized traffic handling is implemented, then traffic prioritization is improved, but collision resolution complexity worsens
Solution Approach 1:
The patent applies local quality by assigning different priority levels to different traffic types and applying collision resolution rules specific to each priority level. High priority traffic receives preferential treatment in collision resolution, while low priority traffic follows standard protocols, allowing differentiated quality of service without requiring completely different resolution mechanisms for each traffic type
Data Source
AI summary
A preamble-based collision detection mechanism for use in wireless local area networks (WLANS), having one or more full-duplex (FD) stations. In addition, a new collision resolution estimation and scheduling mechanism is described for prioritized communication. These techniques can allow for more rapid collision detection and resolution, without the need of performing self-interference (SI) estimation. The techniques includes use of orthogonal preambles, in the time domain and/or frequency domain, into which FD stations embed priority information.