Wireless Sensor Network Scheduling via Child Node Status Verification
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In wireless sensor networks, the simultaneous transmission of RTS packets by multiple sensor nodes can lead to interference and hidden node issues, causing power wastage due to re-transmissions and delays in communication scheduling, especially when RTS packets are lost during the transmission or reception of control packets.
Innovation Solution
A communication scheduling apparatus and method that determines whether a reference node and its child nodes have completed scheduling, allowing the reference node to select a communication time with its parent node only after all child nodes have finished scheduling, using a bit string to prioritize control packets and allocate time slots, thereby minimizing transmission delays and power consumption.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If multiple sensor nodes transmit RTS packets simultaneously, then communication scheduling can be established, but interference and hidden node issues occur causing power wastage due to re-transmissions
Solution Approach 1:
The patent applies preliminary action by having sensor nodes sense the channel status before transmitting RTS packets. Nodes perform channel sensing to detect whether the channel is busy or free, and only transmit RTS packets when the channel is determined to be free. This preliminary channel status check prevents simultaneous transmissions that cause interference and hidden node problems, thereby reducing power wastage from re-transmissions while maintaining communication scheduling efficiency.
2Reliability
If RTS packets are re-transmitted due to loss during control packet transmission, then communication scheduling can be completed, but transmission delays increase
Solution Approach 1:
The patent implements feedback mechanisms through acknowledgment packets sent from destination nodes to source nodes after successful receipt of RTS packets. This feedback allows source nodes to confirm whether their RTS packets were successfully received without requiring re-transmission. The feedback system ensures communication scheduling completion while minimizing transmission delays by providing immediate status information.
Solution Approach 2:
The patent uses preliminary channel sensing before RTS packet transmission to predict potential transmission failures. By checking channel status in advance, nodes can avoid transmitting RTS packets during periods of high interference or channel congestion, thereby preventing packet loss and the subsequent delays associated with re-transmission while ensuring scheduling completion.
3Speed
If communication scheduling is performed without considering child node completion status, then scheduling speed increases, but interference and scheduling conflicts occur
Solution Approach 1:
The patent applies preliminary action by requiring reference nodes to check the completion status of communication scheduling with all child nodes before proceeding to schedule transmissions with parent nodes. This preliminary verification ensures that no scheduling conflicts or interference issues exist in the lower levels of the network hierarchy, thereby maintaining scheduling correctness while enabling efficient progression through the scheduling process.
Data Source
AI summary
An apparatus and method are provided for communication scheduling. The apparatus includes a control unit for determining whether a reference node and a plurality of child nodes of the reference node have completed communication scheduling, which is required for performing communication between the reference node and the child nodes during a time period, based on the reference node; and a scheduling unit for performing the communication scheduling between the reference node and a parent node of the reference node by selecting a communication time, when the communication scheduling between the reference node and the child nodes have been completed.