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Reflected power imposes severe linearity problems to the receiver in radio frequency identification (RFID) readers. In this letter, the design and realization of a ultra high frequency RFID reader with a reflected power canceller circuit based on quadrature feedback are presented. Theory and measurements of the signal and noise in the receiver are presented as a function of incident carrier power. The receiver sensitivity is even better than without the canceller with high incident carrier power: A noise spectral density at the data band is -140 dBm/Hz at +12 dBm incident carrier power. At the same time, input compression point of +15 dBm is achieved. The dynamic range of the receiver is improved by 10 dB.