A low-noise active leakage canceller (ALC) for radio frequency identification (RFID) transceiver is reported. The proposed ALC suppresses the strong transmitter (TX) leakage at the receiver (RX) input through continuous leakage tracking by employing an I/Q harmonic rejection switched-capacitor digital power amplifier (I/Q HR SC DPA). Compared to the analog feedback loop-based ALC, the proposed ALC minimizes the noise figure (NF) degradation in the RX and eliminates the large-size passive components in the analog low pass filter, which leads to high RX sensitivity and small chip area. Implemented in a 55-nm CMOS, the proposed ALC suppresses -10 dBm TX leakage down to -47.2 dBm while degrading the RX NF by 0.4 dB at the offset frequency of 640 kHz.

中文翻译：

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UHF-RFID收发器采用开关电容数字功率放大器的有源漏电消除器


报道了一种用于射频识别（RFID）收发器的低噪声有源泄漏消除器（ALC）。所提出的 ALC 通过采用 I/Q 谐波抑制开关电容器数字功率放大器 (I/Q HR SC DPA) 进行连续泄漏跟踪，抑制接收器 (RX) 输入处的强发射器 (TX) 泄漏。与基于模拟反馈环路的 ALC 相比，所提出的 ALC 最大限度地减少了 RX 中的噪声系数 (NF) 衰减，并消除了模拟低通滤波器中的大尺寸无源元件，从而实现了高 RX 灵敏度和小芯片面积。所提出的 ALC 在 55 nm CMOS 中实现，可将 -10 dBm TX 泄漏抑制至 -47.2 dBm，同时在 640 kHz 偏移频率下使 RX NF 降低 0.4 dB。