目的 设计一种声表面波（SAW）温度传感器抗干扰技术，以提高温度测量的稳定性。方法 分析SAW谐振器（SAWR）回波特性，建立SAWR回波信号熵能量模型，发现SAWR回波信号的衰减过程与熵能量的上升过程对应。当回波信号达到噪声水平时，熵能量的单调上升过程消失。为了抑制正弦干扰设计一种改进型自相关算法，利用该算法对信号进行去噪的同时使谐振器回波信号的衰减特性和正弦干扰的等幅特性得到保持。结果 根据模拟仿真结果设置了SAWR回波信号的检测阈值（Vthre=1），并对该阈值进行了蒙特卡罗仿真实验。仿真结果表明，当信号信噪比大于4 dB时，SAWR回波信号的检测率达到86%，而正弦干扰误检率小于0.5%。最后应用该算法对实际的正弦信号和SAWR回波信号进行了检测，得到的误检率接近于0。结论 实验结果显示，所设计的算法可以用作声表面波温度传感器的抗干扰技术。

The work aims to develop an anti-interference technology for surface acoustic wave (SAW) temperature sensor so as to improve the stability of temperature measurement. The characteristics of surface acoustic wave resonator (SAWR) response were analyzed, and the entropy energy model of SAWR response was established. The attenuation process of SAWR response corresponded to the rising process of entropy energy. The monotonous rising process of entropy energy disappeared when the response signal reached the noise level. An improved auto-correlation algorithm was designed to reduce the influence of the sinusoidal interference. The designed algorithm can remove the noise when maintaining the decay characteristics of the resonator response and the equal-amplitude characteristics of the interference signal. The detection threshold (Vthre=1) of the SAWR response signal was set up based on the simulation results and the Monte Carlo simulation experiments were performed on the threshold value. Simulation results showed that when the signal to noise ratio (SNR) was greater than 4dB, the SAWR response detection rate reached 86%, and false detection rate of the sinusoidal interference was less than 0.5%. Finally, the proposed algorithm was used to detect the actual sinusoidal signal and SAWR response. The false detection rate was close to 0. The experimental results show that the designed algorithm can be used as the anti-interference technology of SAW temperature sensor.