公开(公告)号：EP1865600A2

公开(公告)日：2007-12-12

申请号：EP07116854.6

申请日：2002-01-23

申请人： NEC CORPORATION

发明人： Matsumoto, Mariko ,  Ono, Shigeru

IPC分类号： H03J7/02 ,  H03J1/00

CPC分类号： H03J1/0066 ,  H03J7/02 ,  H03J7/026 ,  H03J2200/02 ,  H03L7/085 ,  H03L7/16 ,  H03L7/235

摘要： A portable radio terminal for realizing automatic frequency control (AFC) for automatically controlling the oscillation frequency of an oscillator includes a unit for intermittently performing AFC operation, and a unit for shortening an AFC operation stop period when the frequency shift of the oscillation frequency is large. An AFC control method is also disclosed.

摘要翻译： 用于实现用于自动控制振荡器的振荡频率的自动频率控制（AFC）的便携式无线电终端包括用于间歇地执行AFC操作的单元和用于当振荡频率的频移大时缩短AFC操作停止时段的单元 。 还公开了AFC控制方法。

公开(公告)号：EP1865599A2

公开(公告)日：2007-12-12

申请号：EP07116852.0

申请日：2002-01-23

申请人： NEC CORPORATION

发明人： Matsumoto, Mariko ,  Ono, Shigeru

IPC分类号： H03J7/02 ,  H03J1/00

CPC分类号： H03J1/0066 ,  H03J7/02 ,  H03J7/026 ,  H03J2200/02 ,  H03L7/085 ,  H03L7/16 ,  H03L7/235

摘要： A portable radio terminal for realizing automatic frequency control (AFC) for automatically controlling the oscillation frequency of an oscillator includes a unit for intermittently performing AFC operation, and a unit for shortening an AFC operation stop period when the frequency shift of the oscillation frequency is large. An AFC control method is also disclosed.

摘要翻译： 用于实现用于自动控制振荡器的振荡频率的自动频率控制（AFC）的便携式无线电终端包括用于间歇地执行AFC操作的单元和用于缩短振荡频率的频移较大时的AFC操作停止时段的单元 。 还公开了AFC控制方法。

公开(公告)号：EP0956644B1

公开(公告)日：2006-05-10

申请号：EP98901032.7

申请日：1998-01-29

申请人： Kabushiki Kaisha Kenwood

发明人： HORII, Akihiro ,  SHIRAISHI, Kenichi

IPC分类号： H03J7/26 ,  H03L7/12 ,  H04L27/227

CPC分类号： H03J7/02 ,  H04L27/2273

摘要： An auto frequency control circuit which can receive a desired signal in a shortest scanning time corresponding to a current reception C/N ratio. A reception C/N ratio is judged by a C/N ratio calculating unit (20) and a comparator (26) in accordance with signal point positions of a received and detected phase shift keying signal. A Vt counter step converting circuit (30) converts the judged reception C/N ratio into a predetermined scanning step frequency width preset for the judged reception C/N ratio in such a manner that a narrower scanning step frequency width is obtained for a lower reception C/N ratio. A frequency control voltage is generated in accordance with the converted scanning step frequency and applied to a VCO (2) to thereby sequentially scan an oscillation output of VCO (2) as a demodulation carrier.

公开(公告)号：EP1653616A2

公开(公告)日：2006-05-03

申请号：EP05017631.2

申请日：2005-08-12

申请人： Broadcom Corporation

发明人： Ibrahim, Brima B. ,  Jensen, Henrik T.

IPC分类号： H03J7/02 ,  H04L27/00

CPC分类号： H03J7/02 ,  H03J2200/02 ,  H04L25/063 ,  H04L27/142 ,  H04L2027/0057 ,  H04L2027/0065

摘要： In RF transceivers, a method and a system for a frequency feedback adjustment in digital receivers are provided. A DC offset may result from the difference in frequencies between an RF transmitter and an RF receiver. An adjustment of the receiver's frequency may be implemented after synchronization occurs and may be performed by utilizing the Forward Error Correction (FEC) repetition rate in a header of a Bluetooth packet. The adjustment may be performed when the frequency difference exceeds a threshold value. In another aspect, adjusting the frequency of the RF receiver may be performed by modifying and/or changing a phase locked loop (PLL) trimmer register. This approach may allow an RF receiver to operate, in some instances, without the need for an equalizer. In this regard, the power consumed by the RF receiver may be minimized and/or the overall cost of the RF receiver may be reduced.

摘要翻译： 在RF收发器中，提供了用于数字接收机中的频率反馈调整的方法和系统。 DC偏移可能由RF发射机和RF接收机之间的频率差引起。 可以在同步发生之后实现接收机频率的调整，并且可以通过利用蓝牙分组的报头中的前向纠错（FEC）重复率来执行。 当频率差超过阈值时，可以进行调整。 在另一方面，可以通过修改和/或改变锁相环（PLL）微调寄存器来调整RF接收机的频率。 这种方法可以允许RF接收机在一些情况下操作，而不需要均衡器。 在这方面，RF接收机消耗的功率可以被最小化，和/或可以降低RF接收机的总体成本。

公开(公告)号：EP1570578A2

公开(公告)日：2005-09-07

申请号：EP03796894.8

申请日：2003-12-10

申请人： Microtune (Texas), L.P.

发明人： DESSERT, David ,  SCHNEIDER, John

IPC分类号： H04B1/00

CPC分类号： H03J7/02 ,  H03D7/161 ,  H04B1/12 ,  H04B15/06

摘要： The present invention is directed to a system and method of reducing frequency interference in a circuit when the harmonics of at least two frequencies could cause interference when such harmonics interact with each other. In one embodiment, a determination is made as to which harmonic could possibly support such interference, and based upon the determined harmonic, determining which combination within said determined harmonic is likely to cause the interference.

公开(公告)号：EP1436909A1

公开(公告)日：2004-07-14

申请号：EP02773674.3

申请日：2002-10-01

申请人： MOTOROLA, INC.

发明人： KING, Thomas, M.

IPC分类号： H04B7/00

CPC分类号： G01S19/235 ,  H03J7/02

摘要： A method in a location enabled mobile wireless receiver having an oscillator, including determining a change in cellular network based frequency error of the oscillator (250), based on a difference (230) between a cellular network based frequency error of the oscillator and a reference cellular network based frequency error (210) of the oscillator, determining a first frequency error of the oscillator by summing (250) a reference satellite positioning system receiver based oscillator frequency error (220) with the change in cellular network based frequency error of the oscillator.

公开(公告)号：EP1217738A3

公开(公告)日：2004-06-16

申请号：EP01129278.6

申请日：2001-12-12

申请人： NEC CORPORATION

发明人： Hokao, Tomoaki

IPC分类号： H03J7/02

CPC分类号： H03J7/02

摘要： A mobile station is disclosed for performing an automatic frequency control based on a correspondence of a frequency error and TCXO control voltage to a base station. A plurality of frequency error measuring units each measure a frequency error between an internal clock signal and a clock signal in a specified base station. A plurality of control voltage calculators, each associated with a corresponding one of the plurality of frequency error measuring units, integrate a frequency error measured by the corresponding frequency error measuring unit to produce a control voltage. A control voltage selector selects a control voltage corresponding to a base station currently in communication with the mobile station from among control voltages calculated by the plurality of control voltage calculators. A clock signal generator generates an internal clock signal at a frequency in accordance with the selected control voltage. A memory has stored therein a set of a scramble code of each base station corresponding to a frequency error measured by a frequency error measuring unit corresponding to the base station, and a control voltage selected by the control voltage selector. Later, when the mobile station switches a base station unitized for the frequency control (hand-over), a frequency error and TCXO control voltage corresponding to a scramble code (or identification ID) of a base station, to which the mobile station is newly connected for communication, are read from the memory, when the scramble code is stored in the memory, for utilizing in the frequency control.

公开(公告)号：EP0899897B1

公开(公告)日：2003-12-17

申请号：EP98104567.7

申请日：1998-03-13

申请人： Marconi Communications GmbH

发明人： Rümmer, Wolfgang ,  Bollmann, Andreas

IPC分类号： H04B7/24 ,  H04J1/06 ,  H04B7/26

CPC分类号： H03J7/02

公开(公告)号：EP1344325A1

公开(公告)日：2003-09-17

申请号：EP01271699.9

申请日：2001-12-17

申请人： Nokia Corporation

发明人： BURGESS, Paul

IPC分类号： H04B1/40 ,  H04L27/16 ,  H04B17/00

CPC分类号： H04L27/1525 ,  H03J7/02 ,  H04B1/40 ,  H04B17/104 ,  H04B17/15 ,  H04L2027/0028 ,  H04L2027/0055 ,  H04L2027/0089

摘要： The application discloses a radio transmission device for receiving/transmitting of radio packets, comprising: a reception means (34) connected to a mixing means (4) via a transmit/receive switch (32) and an amplifying means (30), said mixing means (4) being connected via a demodulation means (12) to a base band processing means (20), wherein said base band processing means (20) is connected via a modulation means (28) to a power amplifying means (42), wherein said modulation means (28) is releasably connected via a phase locked loop circuit (15) to said mixing means (4).

公开(公告)号：EP0962046B1

公开(公告)日：2003-04-02

申请号：EP98903523.3

申请日：1998-01-15

申请人： Scientific-Atlanta, Inc.

发明人： COMAN, Ion ,  HANNA, Kenneth, M.

IPC分类号： H03D7/16 ,  H03J7/02

CPC分类号： H03D7/16 ,  H03D7/165 ,  H03J1/0008 ,  H03J7/02 ,  H03J2200/31

摘要： The present invention relates to an improved demodulator for locking onto and tracking a carrier. Harmonic frequencies are occasionally generated by demodulation circuitry. When this occurs, the harmonic frequencies can interfere with the demodulator's locking and tracking functions, especially if the harmonic frequencies are near a down converted carrier's frequency. A system and method are disclosed which provides an offset to a frequency synthesizer (107) whose output frequency (F1, F2) is used to down convert (104) the carrier. The offset alters the frequency of the down converted carrier so as to shift it away from the interfering harmonics. In this regard, the demodulator is enabled to lock onto and track a carrier when previously not possible.