公开(公告)号：US07937044B2

公开(公告)日：2011-05-03

申请号：US11965492

申请日：2007-12-27

申请人： Hee-Chan Choi ,  Seung-Bum Kim ,  Dong-Woo Lee

发明人： Hee-Chan Choi ,  Seung-Bum Kim ,  Dong-Woo Lee

IPC分类号： H04B1/38

CPC分类号： H04B1/525 ,  G06K7/0008 ,  G06K19/0701 ,  G06K19/0715

摘要： Disclosed is an apparatus and a method for improving the receive (Rx) sensitivity of a portable Radio Frequency IDentification (RFID). The portable RFID reader/writer is equipped with a variable phase shifter which is connected between an antenna and a directional coupler and then changes an impedance in the direction of the antenna in response to controlling a phase shift, a level of a reflection signal if a transmit (Tx) signal of the portable RFID reader/writer reflected by the antenna flows into an Rx path is measured, and then the phase shift of the variable phase shifter is controlled in such a manner as to minimize the measured level of the reflection signal. Therefore, calibration is implemented so that an antenna impedance changing in response to a position in which contact is made by a user's hand may have an adaptively optimal antenna reflection coefficient, thereby improving the Rx sensitivity.

摘要翻译： 公开了一种用于提高便携式射频识别（RFID）的接收（Rx）灵敏度的装置和方法。 便携式RFID阅读器/写入器配备有可变移相器，其连接在天线和定向耦合器之间，然后响应于控制相移而改变天线方向上的阻抗，反射信号的电平如果 测量由天线反射的便携式RFID读写器的发送（Tx）信号流入Rx路径，然后控制可变移相器的相移，使得反射信号的测量电平最小化 。 因此，实现校准，使得响应于由用户的手进行接触的位置而改变的天线阻抗可以具有自适应地最佳的天线反射系数，从而提高Rx灵敏度。

公开(公告)号：US08249194B2

公开(公告)日：2012-08-21

申请号：US12275308

申请日：2008-11-21

申请人： Dong-Woo Lee ,  Yong-Won Shin ,  Hee-Chan Choi

发明人： Dong-Woo Lee ,  Yong-Won Shin ,  Hee-Chan Choi

IPC分类号： H03K9/00

CPC分类号： H04L25/061 ,  H04L27/2647 ,  H04L27/2656

摘要： An apparatus and method for canceling a Direct Current (DC) offset in a Broadband Wireless Access (BWA) communication system are provided. The method includes canceling a DC offset by performing self-calibration in a modulator/demodulator (modem), attempting initial synchronization acquisition in the modem, and if the initial synchronization acquisition succeeds, canceling a DC offset by performing DC offset trace and cancellation.

摘要翻译： 提供一种用于在宽带无线接入（BWA）通信系统中取消直流（DC）偏移的装置和方法。 该方法包括通过在调制解调器（调制解调器）中进行自校准，在调制解调器中尝试初始同步捕获，以及初始同步捕获成功，通过执行DC偏移跟踪和消除来消除DC偏移来消除DC偏移。

公开(公告)号：US20090129494A1

公开(公告)日：2009-05-21

申请号：US12275308

申请日：2008-11-21

申请人： Dong-Woo LEE ,  Yong-Won Shin ,  Hee-Chan Choi

发明人： Dong-Woo LEE ,  Yong-Won Shin ,  Hee-Chan Choi

IPC分类号： H04K1/10

CPC分类号： H04L25/061 ,  H04L27/2647 ,  H04L27/2656

摘要： An apparatus and method for canceling a Direct Current (DC) offset in a Broadband Wireless Access (BWA) communication system are provided. The method includes canceling a DC offset by performing self-calibration in a modulator/demodulator (modem), attempting initial synchronization acquisition in the modem, and if the initial synchronization acquisition succeeds, canceling a DC offset by performing DC offset trace and cancellation.

摘要翻译： 提供一种用于在宽带无线接入（BWA）通信系统中取消直流（DC）偏移的装置和方法。 该方法包括通过在调制解调器（调制解调器）中进行自校准，在调制解调器中尝试初始同步捕获，以及初始同步捕获成功，通过执行DC偏移跟踪和消除来消除DC偏移来消除DC偏移。

公开(公告)号：US20060178111A1

公开(公告)日：2006-08-10

申请号：US11330752

申请日：2006-01-12

申请人： Hee-Chan Choi ,  Hyung-Weon Park

发明人： Hee-Chan Choi ,  Hyung-Weon Park

IPC分类号： H04B1/00 ,  H04B1/10

CPC分类号： H04B1/525 ,  H04B1/109

摘要： A method of canceling noise of a reception module in a wireless transceiver including the steps of determining a filtering band using channel information; generating a switching control signal, selecting a filter to perform filtering according to the determined filtering band; and switching a receive signal received through an antenna of the reception module to the selected filter to perform the filtering using the switches controlled by the switching control signal; and filtering the receive signal using the selected filter. Accordingly, cross modulation (CM) noise of the reception module is canceled.

摘要翻译： 一种在无线收发机中消除接收模块的噪声的方法，包括以下步骤：使用信道信息确定滤波频带; 产生切换控制信号，选择滤波器以根据所确定的滤波频带进行滤波; 以及将通过所述接收模块的天线接收的接收信号切换到所述选择的滤波器，以使用由所述切换控制信号控制的开关来执行所述滤波; 并使用所选择的滤波器对接收信号进行滤波。 因此，接收模块的交叉调制（CM）噪声被消除。

公开(公告)号：US07450906B2

公开(公告)日：2008-11-11

申请号：US11286171

申请日：2005-11-23

申请人： Hee-Chan Choi ,  Hyung-Weon Park

发明人： Hee-Chan Choi ,  Hyung-Weon Park

IPC分类号： H04B1/00

CPC分类号： H04B1/109 ,  H04B1/525

摘要： A method and apparatus are provided for removing cross modulation (CM) noise in a wireless transceiver. A determination is made as to whether a transmission signal to be supplied to a transmitter of the wireless transceiver is present. If the transmission signal is present, a level of the transmission signal is determined. When a value of the transmission signal level is equal to or greater than a predetermined value, a first number of filtering operations are performed on a received signal to be input into a receiver of the wireless transceiver. However, when no transmission signal is present or the value of the transmission signal level is less than the predetermined value, a second number of filtering operations are performed on the received signal to be input into the receiver of the wireless transceiver. The first number of filtering operations being greater than the second number of filtering operations.

摘要翻译： 提供了一种用于去除无线收发器中的交叉调制（CM）噪声的方法和装置。 确定是否存在要提供给无线收发器的发射机的发送信号。 如果发送信号存在，则确定发送信号的电平。 当传输信号电平的值等于或大于预定值时，对要被输入无线收发器的接收机的接收信号执行第一数量的滤波操作。 然而，当不存在传输信号或者传输信号电平的值小于预定值时，对要被输入到无线收发器的接收机的接收信号执行第二数量的滤波操作。 第一数量的过滤操作大于第二数量的过滤操作。

公开(公告)号：US20060111132A1

公开(公告)日：2006-05-25

申请号：US11286171

申请日：2005-11-23

申请人： Hee-Chan Choi ,  Hyung-Weon Park

发明人： Hee-Chan Choi ,  Hyung-Weon Park

IPC分类号： H04B15/00

CPC分类号： H04B1/109 ,  H04B1/525

摘要： A method and apparatus are provided for removing cross modulation (CM) noise in a wireless transceiver. A determination is made as to whether a transmission signal to be supplied to a transmitter of the wireless transceiver is present. If the transmission signal is present, a level of the transmission signal is determined. When a value of the transmission signal level is equal to or greater than a predetermined value, a first number of filtering operations are performed on a received signal to be input into a receiver of the wireless transceiver. However, when no transmission signal is present or the value of the transmission signal level is less than the predetermined value, a second number of filtering operations are performed on the received signal to be input into the receiver of the wireless transceiver. The first number of filtering operations being greater than the second number of filtering operations.

摘要翻译： 提供了一种用于去除无线收发器中的交叉调制（CM）噪声的方法和装置。 确定是否存在要提供给无线收发器的发射机的发送信号。 如果发送信号存在，则确定发送信号的电平。 当传输信号电平的值等于或大于预定值时，对要被输入无线收发器的接收机的接收信号执行第一数量的滤波操作。 然而，当不存在传输信号或者传输信号电平的值小于预定值时，对要被输入到无线收发器的接收机的接收信号执行第二数量的滤波操作。 第一数量的过滤操作大于第二数量的过滤操作。