IEEE Trans Ultrason Ferroelectr Freq Control. 2022 Apr;69(4):1556-1562. doi: 10.1109/TUFFC.2022.3156650. Epub 2022 Mar 30.
Solving the phase ambiguity problem is crucial to achieving a wide-range and high-precision measurement for the frequency-domain sampling (FDS)-based surface acoustic wave (SAW) delay-line sensor systems. This study proposes an improved phase estimation algorithm called dual-band phase estimation (DBPE) to solve the problem. By using DBPE, the SAW sensor system can obtain an extensive and alterable measuring range without further requirements for sensor design or transmitted signals. Thus, it can be widely used in various FDS-based SAW delay-line sensor systems. Monte Carlo simulations and temperature measuring experiments, based on a YZ-cut LiNbO SAW delay-line sensor and a switched frequency-stepped continuous wave (S-FSCW) reader, are performed to demonstrate the algorithm's validity. The Monte Carlo simulations show that DBPE can effectively solve the phase ambiguity problem and has better performance than frequency estimation in measuring precision at a low signal-to-noise ratio (SNR). The temperature-sensing experiments show that DBPE has a good performance in measuring range and precision, serving as a phase ambiguity solver in the temperature sensor system.
解决相位模糊问题对于实现基于频域采样（FDS）的声表面波（SAW）延迟线传感器系统的宽范围和高精度测量至关重要。本研究提出了一种名为双频带相位估计（DBPE）的改进相位估计算法来解决该问题。通过使用 DBPE，SAW 传感器系统可以在不进一步要求传感器设计或传输信号的情况下获得广泛且可改变的测量范围。因此，它可以广泛应用于各种基于 FDS 的 SAW 延迟线传感器系统中。基于 YZ 切型 LiNbO3 SAW 延迟线传感器和切换频率步进连续波（S-FSCW）阅读器进行了蒙特卡罗模拟和温度测量实验，以验证该算法的有效性。蒙特卡罗模拟表明，DBPE 可以有效地解决相位模糊问题，并且在低信噪比（SNR）下的测量精度方面比频率估计具有更好的性能。温度传感实验表明，DBPE 在测量范围和精度方面具有良好的性能，可用作温度传感器系统中的相位模糊解算器。
