公开(公告)号：US20220416824A1

公开(公告)日：2022-12-29

申请号：US17702003

申请日：2022-03-23

申请人： REALTEK SEMICONDUCTOR CORPORATION

发明人： KUAN-YU SHIH ,  HSIAO-TSUNG YEN

IPC分类号： H04B1/04

摘要： The present invention discloses a communication apparatus having feedback calibration mechanism. A signal transmission circuit generates a RF analog signal according to a digital signal. A signal amplifying circuit amplifies the RF analog signal to generate an amplified analog signal. A LC impedance matching circuit transmits the amplified analog signal to the antenna to perform transmission. A feedback calibration circuit includes a feedback inductive circuit and a calibration circuit. A feedback inductive circuit is inductively coupled to the LC impedance matching circuit to receive the amplified analog signal to generate a feedback signal. A calibration circuit determines a distorted amount of the feedback signal relative to the RF analog signal to modify an operation parameter of at least one of the signal transmission circuit and the signal amplifying circuit to decrease the distorted amount.

公开(公告)号：US20220286343A1

公开(公告)日：2022-09-08

申请号：US17678052

申请日：2022-02-23

申请人： REALTEK SEMICONDUCTOR CORPORATION

发明人： KUAN-YU SHIH ,  CHIA-JUN CHANG

IPC分类号： H04L27/36 ,  H04L27/38

摘要： A wireless transceiver having an in-phase quadrature-phase (IQ) calibration function includes a transmitter, a receiver, a signal generator, and a switch circuit. The switch circuit includes a first and a second switch circuits. The first switch circuit is turned on in a receiver-end calibration process, and outputs a predetermined signal from the signal generator to the transmitter. The second switch circuit is turned on in the receiver calibration process and outputs a derivative signal of the predetermined signal from the transmitter to the receiver to let the receiver performs a receiver-end IQ calibration accordingly. The first switch circuit is turned off and the second switch circuit is turned on in a transmitter-end calibration process; the second switch circuit outputs a radio-frequency signal from the transmitter to the receiver to let the receiver generates a calibration reference accordingly; and the transmitter performs a transmitter-end IQ calibration according to the calibration reference.

公开(公告)号：US20180152156A1

公开(公告)日：2018-05-31

申请号：US15818547

申请日：2017-11-20

申请人： REALTEK SEMICONDUCTOR CORPORATION

发明人： KUAN-YU SHIH

IPC分类号： H03F3/45 ,  H03F1/02

CPC分类号： H03F3/45224 ,  H03F1/0211 ,  H03F3/45475 ,  H03F3/45636 ,  H03F3/4565 ,  H03F3/45654 ,  H03F2200/144 ,  H03F2200/267 ,  H03F2200/48 ,  H03F2203/45031 ,  H03F2203/45032 ,  H03F2203/45151 ,  H03F2203/45156 ,  H03F2203/45276 ,  H03F2203/45404 ,  H03F2203/45418 ,  H03F2203/45424 ,  H03F2203/45692

摘要： An operational amplifier and a differential amplifying circuit thereof. The differential amplifying circuit receives a differential input signal and outputs a differential output signal. The differential amplifying circuit includes an output port that has a first terminal and a second terminal, the differential output signal being outputted via the first and second terminals; a first transistor pair receiving the differential input signal via two first ends and coupling to the first and second terminals respectively via two second ends; a second transistor pair receiving the differential input signal via two first ends and coupling to the first and second terminals respectively via two second ends; and a third transistor pair receiving a control signal via two first ends and coupling to the first and second terminals respectively via two second ends. The control signal controls the third transistor pair to switch on or off and/or controls the current flowing therethrough.