Clock Offset and Skew Estimation Based on Correlation Detection with One-way Dissemination in Wireless Sensor Networks

Clock synchronization based on pulse with propagation delay eliminated in wireless sensor networks

“…Assume that at the v th clock tick, the i th node broadcasts a time‐shifted synchronization signal $$s(t-t_{i}(v))$$ at time $$t_{i}(v)$$, and $$s(t)$$ is defined as: $$$$\begin{equation} s(t)=\sum _{n=0}^{2 N_{z}-1} z[n] x{\left(t-n T_{z}\right)} \end{equation}$$$$where $$T_{z}$$ is the pulse spacing with $$2 N_{z} T_{z} \ll T_{0}$$; $$x(t)\in R$$ is a normalized baseband pulse. In (), $$z [n]$$ is a synchronization sequence of length $$2N_{z}$$ constructed by two Zadof–Chu (ZC) sequences of length $$N_{z}$$ with roots u and $$-u$$, respectively, which is recorded as [10]: …”

“…is a synchronization sequence of length 2N z constructed by two Zadof-Chu (ZC) sequences of length N z with roots u and −u, respectively, which is recorded as [10]:…”

“…[9] estimates clock skew and offset of UE regarding gNB clock as the reference, where the fixed propagation delay is directly obtained from time advance (TA) included in 5G frames. As reported in [10], an universal pulse-based joint estimation algorithm of clock skew and offset in WSNs is introduced with the propagation delay estimated under a reference clock. In addition, typical pulse-based synchronization methods without reference clock are presented in [11][12][13].…”

A Regular Pattern of Timestamps Between Machines with Built-in System Time

“…T IMESTAMPS or the reported time of a current event, is the essence of time-based applications. Regarding time synchronization, for instance, all devices must report the same time at the same instant, regardless of their connection through network [1][2][3]. Meanwhile, timestamps of sending and receiving packets are collected to measure communication delay over network [3,4].…”

“…Regarding time synchronization, for instance, all devices must report the same time at the same instant, regardless of their connection through network [1][2][3]. Meanwhile, timestamps of sending and receiving packets are collected to measure communication delay over network [3,4]. Another application, namely clock skew estimation [5,6], intends to measure the difference in the frequency rate between the time sources, or the clocks, of two devices.…”