专利快速检索-快速检索全球专利，免费商用专利数据库-IPRDB

1. 发明专利

GB2416968A Clock circuit for RFID tag which forces a change in oscillator state in response to transition in received signal to achieve immediate synchronisation 未知
公开(公告)号：GB2416968A
公开(公告)日：2006-02-08
申请号：GB0417140
申请日：2004-07-30
申请人： HEWLETT PACKARD DEVELOPMENT CO
发明人： CASTLE ROBERT JOHN
IPC分类号： H04L7/033 , G06K19/07 , H03L3/00 , H03L7/24
摘要： The circuit comprises a basic RC oscillator with switches 600. Synchronisation switches 601,603 are added to this. Upon detection of a change of state in the incoming data stream a control circuit (not shown) determines the current state of the clock (high/low) and then closes either of switches 601,603 as appropriate. This has the effect of short circuiting the resistance in the oscillator and forcing a near instantaneous change of state by rapidly (dis)charging the capacitor. The clock oscillator is thereby brought rapidly into synchronisation with the data stream. An alternative embodiment using a pair of capacitors and current mirrors is shown in Fig. 9. The synchronisation circuit is simple and low power and therefore suitable for application in inductively powered RFID tags.

2. 发明专利

GB2413195A A memory tag and reader with password protection of tag memory 未知
公开(公告)号：GB2413195A
公开(公告)日：2005-10-19
申请号：GB0408597
申请日：2004-04-17
申请人： HEWLETT PACKARD DEVELOPMENT CO
发明人： CASTLE ROBERT JOHN , DICKIN FRASER JOHN
IPC分类号： G06F12/14 , G06K19/07 , G06K19/073 , H04Q5/22
摘要： A memory tag in the form of a radio frequency identification tag (RFID) includes a memory storing data, an operating program and a current password. The memory tag is operable, in response to a read signal 64 from a tag reader requesting data 67, to run the operating program to check the read signal for inclusion of a token 66 dependent upon the current password. If the token is identified within the reader signal, the memory tag is operable to read the requested data and transmit it to the reader 72, 73. The token may be the password itself, or a derivative of the password. The tag password may be set at the time of manufacture, or updated after each communication from the tag to the reader. Alternatively the tag receives a new password from the reader after transmitting the requested data. The current token and new passwords may be sent in encrypted form.

3. 发明专利

DE60213929T2 未知
公开(公告)号：DE60213929T2
公开(公告)日：2007-03-01
申请号：DE60213929
申请日：2002-06-27
申请人： HEWLETT PACKARD DEVELOPMENT CO
发明人： CASTLE ROBERT JOHN , WATERS JOHN DERYK
IPC分类号： H04B5/02 , H04L12/28 , H04B7/26 , H04L12/56 , H04L29/06 , H04W8/26 , H04W84/10
摘要： A method is disclosed of controlling a proximity transaction between first and second communications devices (P1 and M1), each of which is provided with a short-range transceiver (3, 1). The first communications device (P1) has an RF/ID reader (5), and the second communications device (M1) has an RF/ID tag (6), the RF/ID tag containing the same identifier information as the second communications device. The second communications device (M1) is positioned within the range of the reader (5) of the first communications device (P1). Then, the transceiver (1) of the second communications device (M1) transmits a transaction request and the identifier information of that device to the first communications device (P1). The reader (5) of the first communications device (P1) then interrogates the tag (6) of the second communications device (M1), and the transaction is completed upon the reader (5) of the first communications device (P1) receiving identifier information from the tag (6) of the second communications device (M1) that is identical to the identifier information already received.

4. 发明专利

GB2413197A A memory tag and reader with password protection of tag memory 未知
公开(公告)号：GB2413197A
公开(公告)日：2005-10-19
申请号：GB0505188
申请日：2005-03-15
申请人： HEWLETT PACKARD DEVELOPMENT CO
发明人： DICKIN FRASER JOHN , CASTLE ROBERT JOHN
IPC分类号： G06F12/14 , G06K19/07 , G06K19/073 , H04Q5/22
摘要： A memory tag in the form of a radio frequency identification tag (RFID) includes a memory storing data, an operating program and a current password. The memory tag is operable, in response to a read signal 64 from a tag reader requesting data 67, to run the operating program to check the read signal for inclusion of a token 66 dependent upon the current password. If the token is identified within the reader signal, the memory tag is operable to read the requested data and transmit it to the reader 72, 73. If the current token is not identified within the reader signal 71, the memory tag does nothing so as to avoid announcing its presence in any way. The token may be the password itself or a derivative of the password. The tag password may be set at the time of manufacture, or updated after each communication from the tag to the reader. Alternatively the tag receives a new password from the reader after transmitting the requested data. The current token and new passwords may be sent in encrypted form.

5. 发明申请

WO2007118906A3 METHOD FOR THE MODULATION OF A CARRIER IN PHASE AND IN AMPLITUDE 审中-公开
标题翻译：在相位和幅度中调制载波的方法
公开(公告)号：WO2007118906A3
公开(公告)日：2008-01-17
申请号：PCT/EP2007053864
申请日：2007-04-19
申请人： HEWLETT PACKARD DEVELOPMENT CO , CASTLE ROBERT JOHN , WATERS JOHN
发明人： CASTLE ROBERT JOHN , WATERS JOHN
IPC分类号： H04L27/32 , G06K7/00 , H04L27/34
CPC分类号： H04L27/32 , H04L27/34
摘要： A method for modulating a signal transmitted by a first device to a second device which is energised by the signal, wherein the first device is further arranged to amplitude modulate the signal so as to transmit data thereon, the method further comprising phase modulating the signal. In a further aspect, changes in amplitude due to the presence of the phase modulation, are corrected in the first device when receiving a signal from the second device.
摘要翻译：一种用于将由第一设备发送的信号调制到由信号激励的第二设备的方法，其中所述第一设备还被布置为对所述信号进行幅度调制以在其上传输数据，所述方法还包括对所述信号进行相位调制。在另一方面，当从第二设备接收到信号时，在第一设备中校正由于存在相位调制引起的幅度变化。

6. 发明专利

GB2437350A Data and Power Transmission via an Amplitude and Phase/Frequency Modulated Signal 未知
公开(公告)号：GB2437350A
公开(公告)日：2007-10-24
申请号：GB0607671
申请日：2006-04-19
申请人： HEWLETT PACKARD DEVELOPMENT CO
发明人： CASTLE ROBERT JOHN , WATERS JOHN DERYK
IPC分类号： H04B5/02 , G06F1/26 , G06K7/00 , H04Q7/32 , H04Q7/38
摘要： A passive near field communication device (12, fig. 8) receives a radio frequency (RF) signal from a transceiver (10) which both powers up the device and supplies data via amplitude modulation (AM), further modulated by a phase shift or frequency spread. The phase variation is such that the transitions (eg. 32 to 32a) can occur at small modulation index without causing ripple in the power supply by changing the magnitude of the signal, and a pseudo-random binary sequence prevents unwanted spectral components. Interference with other 2.4 GHz devices using low index AM (eg. RFID, memory spot, WiFi) is minimised by spreading the signal frequency over a larger bandwidth, ie. reducing the Power Spectral Density (PSD), and amplitude variations from such frequency spreading modulation can be monitored and corrected.

7. 发明专利

GB2423674A Writing to transponder devices 未知
公开(公告)号：GB2423674A
公开(公告)日：2006-08-30
申请号：GB0503845
申请日：2005-02-25
申请人： HEWLETT PACKARD DEVELOPMENT CO
发明人： CASTLE ROBERT JOHN , WATERS JOHN DERYK
IPC分类号： H04B1/59 , G01S13/75
摘要： A read-write device, a controller for a read-write device, a transponder, a method of operating a transponder device, and a method of transmitting data for reading and transmitting data to a transponder device, the read-write device being operable to receive a training bit sequence from a transponder device, calculate an operating frequency for the transponder device from the training bit sequence, and transmit data to the transponder device substantially at the operating frequency. The read-write device can have a reader clock. The bit length correspond to the number of clock-cycles. The read-write device can vary the bit-length of the training sequence. The transponder can have a memory tag clock.

你已经成功收藏专利！

检索式保存成功!

IPRDB

热门服务

关于我们

友情链接

联系方式