Patent ID: 9520902
Filing Date: 2016-12-13
CPC Classification: G06K,H04B

Claim Text:
1. A reader, comprising: a power amplifier, configured to output a first Radio Frequency (RF) transmission signal; a low-noise amplifier, configured to transmit a first RF response signal according to the first RF transmission signal; a circulator, coupled between the power amplifier and the low-noise amplifier, configured to transmit the first RF transmission signal to an RF connection node or receive the first RF response signal from the RF connection node; an automatic-matching-and-tuning circuit, coupled to the circulator, configured to perform impedance matching between the RF connection node and the circulator; a control circuit, coupled to the automatic-matching-and-tuning circuit, configured to adjust the automatic-matching-and-tuning circuit to perform impedance matching between the RF connection node and the circulator, the first RF response signal carrying an upper-tag signal and a lower-tag signal; a mixer, coupled to the low-noise amplifier, configured to down-convert the first RF response signal; and a selectable filter, coupled to the mixer, configured to filter the down-convert upper-tag and lower-tag signals, and select a clearer one from the filtered upper-tag and lower-tag signals to output.