中文摘要：

论述了基于智能天线的RFID接收机中IQ解调的基本原理和实现方法.运用ADI公司PLL ADF4350输出本振信号与固定IF调制信号在IQ解调器ADL5380混频得到IQ基带信号,然后进行滤波和调理,并送入模数转换器AD7352中进行数字化.经测试表明：本设计在中心频率837.5 MHz的10 M带宽内可以很好地实现RFID接收机中IQ解调的功能.

英文摘要：

The theory and implementation of the IQ demodulator in the RFID receivers based on the smart antenna is described. The IQ baseband signal is obtained from ADL 5380 by mixing the local oscillator signal generated by the PLL with the modulated signal. After a series of processes, such as filtering, the baseband signal is digitized in the ADC AD7352. The test resuh shows that the designed circuit can accomplish the IQ demodulation in the RFID receivers in 10M bandwidth at the center frequency 837.5 MHz.