公开(公告)号：US20180040953A1

公开(公告)日：2018-02-08

申请号：US15227614

申请日：2016-08-03

Applicant: NXP B.V.

Inventor： Michael Gebhart ,  Fred George Nunziata ,  Hubert Watzinger

IPC: H01Q3/30 ,  H01Q1/22

CPC classification number: H01Q3/30 ,  H01Q1/2291 ,  H04B5/0031 ,  H04B5/0056

Abstract: A Near Field Communication (NFC) enabled device is disclosed. The NFC device includes an antenna. The NFC device also includes an impedance matching network, a carrier frequency generator to generate a carrier wave, a receiver for receiving a magnetic induction wave, a transmitter, a driver circuit configured to alter an impedance of an antenna network associated with the antenna between a first impedance and a second impedance and a control unit. The control unit is configured to derive a first phase difference between the received magnetic induction wave and an internal clock at the first impedance and a second phase difference between the received magnetic induction wave and the internal clock at the second impedance. The control unit is further configured to change a phase of the carrier wave based on a difference between the first phase difference and a second phase difference.

公开(公告)号：US20160112028A1

公开(公告)日：2016-04-21

申请号：US14885208

申请日：2015-10-16

Applicant: NXP B.V.

Inventor： Thomas Baier ,  Michael Gebhart

IPC: H03H7/40 ,  H01Q7/00 ,  H01L23/495 ,  H01Q1/50

CPC classification number: H03H7/40 ,  H01L23/495 ,  H01L2924/0002 ,  H01Q1/50 ,  H01Q7/00 ,  H01L2924/00

Abstract: An apparatus and method are described for automatically matching the impedance of an antenna. An impedance matching network includes at least one variable impedance element and has an input for receiving a drive signal and an output connectable to an antenna. The impedance matching network includes a shunt capacitor in series between the input and output. A phase measuring measures the phase difference between the voltage and the current of the drive signal using the voltage drop across the shunt capacitor and outputs a measured phase signal. A voltage measuring circuit measures the magnitude of the voltage of the drive signal and the voltage drop across the shunt capacitor and outputs a measured drive voltage signal and shunt capacitor voltage signal. An automatic impedance matching circuit can output a control signal to adjust the impedance of the variable impedance element and determines the impedance of the impedance matching network from the measured phase, drive voltage and shunt capacitor voltages automatically to reduce the difference between the determined impedance of the impedance matching network and the impedance of the antenna.

Abstract translation: 描述了一种用于自动匹配天线的阻抗的装置和方法。 阻抗匹配网络包括至少一个可变阻抗元件，并且具有用于接收驱动信号的输入和可连接到天线的输出。 阻抗匹配网络包括输入和输出之间串联的并联电容器。 相位测量使用分流电容器两端的电压降来测量驱动信号的电压和电流之间的相位差，并输出测得的相位信号。 电压测量电路测量驱动信号的电压幅度和分流电容器两端的电压降，并输出测量的驱动电压信号和分流电容器电压信号。 自动阻抗匹配电路可以输出控制信号来调节可变阻抗元件的阻抗，并自动测量阻抗匹配网络的阻抗，从测量的相位，驱动电压和并联电容器电压自动减小所确定的阻抗之间的差异 阻抗匹配网络和天线的阻抗。

公开(公告)号：US09997829B2

公开(公告)日：2018-06-12

申请号：US15227614

申请日：2016-08-03

Applicant: NXP B.V.

Inventor： Michael Gebhart ,  Fred George Nunziata ,  Hubert Watzinger

IPC: H01Q3/30 ,  H01Q1/22

CPC classification number: H01Q3/30 ,  H01Q1/2291 ,  H04B5/0031 ,  H04B5/0056

Abstract: A Near Field Communication (NFC) enabled device is disclosed. The NFC device includes an antenna. The NFC device also includes an impedance matching network, a carrier frequency generator to generate a carrier wave, a receiver for receiving a magnetic induction wave, a transmitter, a driver circuit configured to alter an impedance of an antenna network associated with the antenna between a first impedance and a second impedance and a control unit. The control unit is configured to derive a first phase difference between the received magnetic induction wave and an internal clock at the first impedance and a second phase difference between the received magnetic induction wave and the internal clock at the second impedance. The control unit is further configured to change a phase of the carrier wave based on a difference between the first phase difference and a second phase difference.