A Comparison of Opportunistic Signals for Wireless Syntonization Using the Modified Cramér–Rao Lower Bound. Issue 3 (11th September 2017) - Tröger, Hans‐Martin
Abstract: The exact adjustment of the oscillators within a wireless sensor network is one basic requirement for precise time difference of arrival localization methods. Typically, GPS is used for the required syntonization of the oscillators, but its performance is not sufficient for high‐precision network timing. In contrast, a wired clock distribution is very cumbersome and expensive. In this article, we describe a new method of adjusting the oscillators of distributed receiver nodes with the help of so‐called Signals of Opportunity (SoO). We derive the required signal properties of optimal SoO, and we show that Orthogonal Frequency Division Multiplexing (OFDM)‐based waveforms offer ideal properties. After a discussion of the OFDM signal structure, we compare different OFDM signals with the help of the Modified Cramér–Rao Lower Bound (MCRLB) regarding their syntonization performance. We also show how signal decision can be used to further improve the accuracy. Finally, we prove our theoretical bounds by means of simulation results. Copyright © 2017 Institute of Navigation