Terminal Radio-Resource Switching for Collision Avoidance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing radio communication systems in vehicular networks face challenges with message collisions, particularly in applications where consecutive message losses are problematic, such as platooning, due to the lack of centralized scheduling units.
Innovation Solution
A decentralized collision avoidance strategy is implemented using terminals that send messages on a first radio resource, receive responses, and based on these responses, decide to change to a second radio resource to minimize collisions, utilizing techniques like scaling factors, movement and position information, and negative receipt acknowledgments to optimize spectral efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a decentralized collision avoidance strategy is implemented without a central scheduling unit, then device complexity is reduced and autonomy is improved, but message collisions increase and reliability deteriorates
Solution Approach 1:
The patent implements feedback mechanisms where terminals monitor collision indicators (such as receipt acknowledgments from other terminals) and use this information to dynamically adjust their resource selection. Terminals send messages and receive feedback about successful deliveries, then modify their resource choices based on this feedback to avoid future collisions, enabling decentralized collision avoidance without central scheduling.
Solution Approach 2:
The patent changes the parameters of radio resource selection by introducing collision indicators and adjusting resource selection probabilities based on observed collision patterns. Terminals modify their transmission parameters (resource selection, timing, frequency) dynamically based on collision experience, allowing adaptive collision avoidance in a decentralized manner.
2Difficulty of detecting and measuring
If terminals send responses to confirm message receipt, then collision detection capability is improved, but spectral efficiency decreases due to increased message traffic
Solution Approach 1:
The patent applies partial action by having only some terminals send response messages rather than all terminals. Terminals use scaling factors to determine the probability or number of responses sent, sending fewer responses than would be needed for complete acknowledgment from all terminals, thus maintaining collision detection capability while reducing spectral efficiency degradation.
Solution Approach 2:
The patent makes response messages multi-functional by having them serve both as collision detection indicators and as acknowledgments of message receipt. The same response mechanism provides multiple benefits (collision detection, delivery confirmation, resource selection feedback) without requiring separate message types, improving spectral efficiency.
3Reliability
If the first terminal changes radio resources rapidly based on collision responses, then message delivery reliability is improved, but loss of time increases due to frequent resource switching
Solution Approach 1:
The patent applies preliminary action by having terminals pre-select multiple candidate radio resources in advance and pre-evaluate their suitability based on current collision indicators. When a collision is detected, terminals can quickly switch to a pre-selected alternative resource without extensive processing or search time, reducing the time penalty associated with resource switching while maintaining high delivery reliability.
Data Source
AI summary
A first terminal of a radio communications network. The first terminal includes at least one processor, at least one memory with computer program code, and at least one communication module and at least one antenna. The computer program code is configured in such a way that, using the processor, the communication module, and the antenna, it causes the first terminal to send first messages on a first radio resource to a group of further terminals, to receive at least one response, after sending the particular first message, from at least one of the further terminals of the group, to ascertain a resource change decision as a function of the at least one response, and to send second messages as a function of the resource change decision on a second radio resource to the group of further terminals, the second radio resource being different from the first radio resource.