Asynchronous System Channel Access Interference Mitigation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Asynchronous and synchronous wireless communication systems face interference challenges when sharing the same frequency spectrum, leading to inefficiencies in channel access and increased message collisions, particularly in contexts like Intelligent Transport Systems (ITS) where V2X technologies are involved.
Innovation Solution
A method where an asynchronously-based system assesses the channel occupancy duration and spreads out its message transmissions relative to the end of a cycled transmission time allocated for a synchronous-based system, using processing circuitry to delay or shift message times to avoid interference and prevent channel bottlenecks.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If asynchronous and synchronous systems share the same frequency spectrum, then spectrum utilization is improved, but interference and message collisions increase
Solution Approach 1:
The system performs preliminary actions by having the asynchronous system assess channel occupancy duration and spread out message transmissions before they occur. The method evaluates whether the channel is too busy relative to thresholds corresponding to synchronous frames or subframes, and preemptively adjusts transmission timing to avoid collisions with synchronous system transmissions.
Solution Approach 2:
The system dynamically adjusts transmission parameters based on real-time channel conditions. The asynchronous system modifies its transmission schedule by spreading out messages over time, dynamically determining optimal transmission moments based on ongoing channel occupancy assessment, rather than using fixed transmission patterns.
2Productivity
If the asynchronous system transmits messages continuously, then productivity is improved, but channel access efficiency deteriorates due to contention and queueing
Solution Approach 1:
The system implements periodic action by assessing channel occupancy in periodic cycles and spreading out transmissions accordingly. The method evaluates channel conditions periodically (assessing whether channel is too busy relative to thresholds) and adjusts transmission timing based on these periodic assessments, creating a rhythm that prevents continuous contention while maintaining throughput.
Solution Approach 2:
The system performs preliminary assessment of channel occupancy duration before transmissions occur. By evaluating whether the channel is too busy relative to thresholds corresponding to synchronous frames or subframes in advance, the asynchronous system preemptively schedules transmissions to avoid contention, improving both productivity and channel access efficiency.
Data Source
Figure 1A
Figure 1B
Figure 2
AI summary
In connection with an RF communication system, exemplary aspects involve a method for use in a communication system in which a first system (e.g., 802.11) that is asynchronously based and which is susceptible to interference from a second system (e.g., synchronous-based LTE-CV2X). Such interference is due to the frequency spectrum used by the first and second systems overlapping. To mitigate interference issues, example methods spreads out the times for messages in the first system, based on information concerning occupancy of the channel, and transmitting them relative to the end of a cycled transmission allocated for use by the second system.