C-ITS Transmission Restriction Control Message for Congestion Handling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current congestion mitigation methods in Cooperative Intelligent Transport Systems (C-ITS) are unreliable due to decentralized control, where each station independently determines when to reduce transmission rates, leading to inconsistent and slow responses to congestion, and the 'hidden station problem' where some units fail to transmit in congested conditions.
Innovation Solution
A method involving the creation and broadcast of a transmission restriction control message with restriction instructions and validity information, which on-board units must adhere to, to manage message transmission and reduce congestion effectively.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Extent of automation
If decentralized congestion control is implemented where each station independently determines when to reduce transmission rates, then device complexity and autonomy are improved, but reliability and response consistency deteriorate due to implementation differences and slow reaction times
Solution Approach 1:
A centralized congestion control entity acts as an intermediary between congested stations and other network participants. This mediator receives congestion notifications, determines appropriate mitigation measures, and sends control messages to relevant stations, ensuring consistent and reliable congestion handling while maintaining automated response
Solution Approach 2:
The system implements a feedback mechanism where congestion is detected and notified to a centralized entity, which then responds with control messages to adjust transmission rates. This closed-loop feedback ensures reliable congestion mitigation by continuously monitoring and adjusting based on actual network conditions
2Stability of the object's composition
If broadcast technologies use 'listen before talk' mechanism, then collision avoidance is improved, but productivity deteriorates due to the hidden station problem where some stations fail to transmit in congested conditions
Solution Approach 1:
The centralized congestion control entity serves as a mediator that has global visibility of network congestion status. It can identify hidden station problems and coordinate transmissions to ensure all stations, including those that would otherwise remain silent, can transmit necessary messages during congestion events
Solution Approach 2:
The system applies different transmission strategies to different stations based on their local situation and the centralized entity's assessment. Stations that would normally be restricted by listen-before-talk can be granted local transmission permissions when the centralized controller determines it is appropriate, improving overall transmission efficiency
Data Source
Figure 1~2
Figure 3~4
Figure 5~6
AI summary
A method for message control in a cooperative intelligent transport system comprises creating (S3) of a transmission restriction control message. The transmission restriction control message comprises restriction instructions, defining how a transmission restriction demand is to be applied by an on board unit, and validity information. The transmission restriction control message is broadcasted (S4). A method for message control in a cooperative intelligent transport system comprises receiving, in an on board unit, a transmission restriction control message. The transmission restriction control message comprises restriction instructions, defining how a transmission restriction demand is to be applied by the on board unit, and validity information. It is determined whether or not the on board unit fulfils the validity information. If the on board unit fulfils the validity information, the transmissions of messages from the on board unit are adapted according to the restriction instructions. Corresponding apparatuses are also disclosed.