CQF Input Synchronization Using Timing Marker Frames
Solution Overview
Problem
Current CQF systems face misalignment issues due to long link delays, requiring time synchronization among all network devices, which reduces flexibility and efficiency.
Innovation Solution
A method involving the transmission of a timing marker frame (TMF) and phase offset message (POM) allows devices to synchronize their cycle times without needing complete time synchronization, adjusting the receiver's cycle phase to match the transmitter's cycle phase offset by link delay.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If time synchronization protocols are used among all network devices, then cycle alignment is achieved, but system complexity and overhead increase
Solution Approach 1:
The patent extracts the synchronization function from a global time synchronization protocol and implements it locally through the TMF mechanism. Each device independently determines its cycle phase offset based on received TMFs from its specific peer devices, eliminating the need for comprehensive network-wide time synchronization protocols while achieving the necessary cycle alignment for CQF operation
Solution Approach 2:
The timing marker frame serves as an intermediary that carries synchronization information between transmitting and receiving devices. The TMF enables devices to exchange phase reference information without requiring direct time synchronization protocols, acting as a mediator that facilitates cycle alignment through simple frame-based communication
2Measurement precision
If complete time synchronization is implemented, then packet assignment accuracy is improved, but communication flexibility is reduced
Solution Approach 1:
The patent implements local quality by determining cycle phase offsets independently for each transmitting-receiving device pair rather than enforcing uniform global time synchronization. Each device adjusts its cycle phase based on local observations of TMFs from its specific peers, allowing different parts of the network to operate with different phase relationships while maintaining packet assignment accuracy for each connection
Solution Approach 2:
The system dynamically determines cycle phase offsets based on actual observed timing relationships between devices. Rather than using static pre-configured synchronization parameters, devices continuously adjust their cycle phases based on received TMFs, enabling adaptive packet assignment that maintains accuracy while accommodating varying network conditions and link delays
3Reliability
If cycle phase alignment is achieved through synchronization protocols, then packet transmission reliability is improved, but processing time is increased
Solution Approach 1:
The transmitting device preliminarily determines the cycle phase offset and embeds it in the TMF before transmission. The receiving device uses this pre-provided offset information to immediately adjust its cycle phase without requiring iterative synchronization exchanges, achieving packet transmission reliability while minimizing synchronization processing time through advance preparation of phase information
Data Source
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Figure 2B
AI summary
According to embodiments, a first device transmits a timing marker frame (TMF) in a first transmission cycle. The first device determines a transmission time of the TMF. The first device determines a time difference between the transmission time of the TMF and a start time of a second transmission cycle. The first device transmits to a second device a phase offset message (POM) indicating the time difference. The first device transmits frames in a transmission cycle subsequent to the first transmission cycle.