Periodic Signal Monitoring With Internal Clock Drift Correction

The monitoring device uses its own internal clock to establish time reference and detect drift, making the system self-sufficient without external GNSS or network synchronization. The device monitors its internal time drift and automatically adjusts the monitoring window to maintain alignment with the TDD signal frame structure.

The patent replaces expensive and complex external time synchronization systems (GNSS receivers, network decoding infrastructure) with a simple internal clock that can be easily implemented in cost-effective hardware. The internal clock serves as a sufficient substitute for high-precision external time sources in this specific monitoring application.

The internal clock acts as an intermediary between the monitoring device and the TDD signal. Instead of directly relying on external GNSS signals that are blocked in indoor environments, the device uses its internal time reference to track the TDD frame structure, effectively mediating the synchronization requirement.

The system becomes self-sufficient by using its own internal clock rather than depending on external time sources. This self-service approach allows the monitoring device to operate independently in environments where GNSS signals are unavailable, such as indoor factories.

The patent extracts only the essential time reference information from the TDD signal without performing full physical layer decoding. By taking out just the frame structure timing information needed for monitoring and comparing it with the internal clock, the system achieves compatibility with TDD networks while avoiding the complexity of complete signal decoding.

The complex mechanical/electronic process of physical layer decoding is replaced with a simpler time comparison mechanism. Instead of decoding the entire signal structure, the system simply compares the internal clock time with the expected frame timing to detect drift and adjust the monitoring window accordingly.