Abstract: The continuously increasing number of applications for RFID systems also leads to an increase of the performance estimation for RFID systems. The RFID technology is considered to be able to enhance the efficiency of supply chain greatly. Although companies, such as Wal-Mart, have already issued to apply the RFID, this technology has not achieved the expected performance. To study the performance of RFID technology under fading channels, this paper has analyzed its modulation and coding technique, and derived the Bit Error Rate（BER） of backscatter modulation. The Tag Error Rate（TER） under the Nakagami-m fading channel is derived, and some simulation results for different fading and coding parameters are showed and analyzed. The results show that the larger the parameter of fading and repetition coding, the lower the TER.

Key words: Radio Frequency Identification（RFID）, Nakagami-m fading channel, repetition coding, Tag Error Rate（TER）

摘要： 随着RFID技术应用领域的增加，RFID系统性能的评估也日趋重要。为了评估RFID技术在衰落信道下的性能，分析了RFID系统中的调制与编码技术，通过分析反向散射调制的误码率，导出了Nakagami-m衰落信道下标签的错误率，给出了不同信道衰落参数和编码参数下的数值仿真结果。结果表明，衰落参数越大，重复编码次数越多，标签错误率越低。

关键词: 射频识别, Nakagami-m衰落信道, 重复编码, 标签错误率