中文摘要：

为降低声表面波（SAW）射频标签（RFID）系统对硬件模数转换器和天线开关速度及隔离度的要求，提出了频率步进原理声表面波射频标签的辨识。采用基于自回归模型的功率谱估计方法对回波信号进行了时频变换，通过对加入了噪声的系统回波信号进行仿真实验，验证了发射频率步进脉冲信号取代传统窄脉冲的可行性以及算法的高精度。同时也讨论了阅读器与标签之间不同距离、温度影响和相位噪声对标签解码的影响，提出了解决思路。

英文摘要：

In order to reduce the requirements of the speed of analog-to-digital conversion, the antenna switch isolation and speed in surface acoustic waves （SAW） based radio frequency identification （RFID） system, an approach based on frequency stepped continuous wave （FSCW） is proposed. By using the power spectral estimation based on auto-regressive model, the time-frequency transformation of the reflection signal is implemented. The simulation validates the feasibility of emitting FSCW signal instead of traditional narrowband impulse and the higher precision of the algorithm. In addition, some factors such as Doppler Effect, temperature and reflection phase from each reflector, which can influence the precision of spectral estimation are discussed.