公开(公告)号：JP2002237854A

公开(公告)日：2002-08-23

申请号：JP2001207789

申请日：2001-07-09

Applicant: IBM

Inventor： HIRT WALTER ,  GFELLER FRITZ

IPC: H04B10/00 ,  H04B10/08 ,  H04L1/20 ,  H04L25/02 ,  H04L25/49

Abstract: PROBLEM TO BE SOLVED: To provide a method and device for achieving a reliable communication link by deciding the quality of a digital signal, preferably of an infrared signal. SOLUTION: In this device and method for deciding the quality of a digital signal s, n(n>=1) pieces of incoming digital signals S are sampled based on defined pulse width by using a clock cycle CLK. Then, an edge detector 20 detects the edge position of the pulse of the sampled digital signal, and a counter 30 counts clock cycles between at least the first edge and second edge detected by the edge detector. Then, a deviation detector 40 compares a counted clock cycle EEC with a stored reference value EEC0, and provides a deviation value RJ as the index of the instantaneous quality of the digital signal S. This deviation value RJ is supplied to a rework unit, and the rework unit supplies a value J as the index of the quality of the digital signal.

公开(公告)号：JP2002141873A

公开(公告)日：2002-05-17

申请号：JP2001207719

申请日：2001-07-09

Applicant: IBM

Inventor： GFELLER FRITZ ,  HIRT WALTER

IPC: H04B14/02 ,  H04B14/04 ,  H04L25/49

Abstract: PROBLEM TO BE SOLVED: To provide a device and a method for determining the pulse position of a signal encoded by pulse modulation. SOLUTION: In the device and the method for determining pulse position of signal encoded by pulse modulation, a signal can be received as a first component PCS and a second component DCS at least. A first storage unit 102 stores one symbol of the first component PCS at least and a second storage unit 104 stores one symbol of the second component DCS at least. A determination unit 118 is provided with a probability table 110 and when receiving the first and second components PCS and DCS, the address of this table is designated by at least one symbol of the first component PCS and at least one symbol of the second component DCS. Thus, the probability table 110 provides a value to be defined as a pulse position DDS.

公开(公告)号：WO2004017569A3

公开(公告)日：2004-07-15

申请号：PCT/IB0303703

申请日：2003-08-06

Applicant: IBM ,  GFELLER FRITZ ,  HIRT WALTER

Inventor： GFELLER FRITZ ,  HIRT WALTER

IPC: G01S19/48 ,  H04L12/28 ,  H04W64/00

CPC classification number: H04W64/00 ,  G01C21/206 ,  G01S5/0252

Abstract: The present invention is related to an apparatus and method for determining the location of a communication device within a wireless network in order to provide a geolocation functionality to the communication device participating under an access protocol of a wireless local-area network (WLAN) infrastructure such as IEEE 802.11 or Hiperlan. The apparatus comprises at least two transponder units for communicating with the communication device when the communication device is situated in a coverage area of the wireless network and a processing unit for deriving the location of the communication device within the coverage area in dependence on information received from the transponder units.

Abstract translation: 本发明涉及用于确定无线网络内的通信设备的位置的设备和方法，以便为参与无线局域网（WLAN）基础设施的接入协议的通信设备提供地理定位功能性， 作为IEEE 802.11或Hiperlan。 该装置包括至少两个转发器单元，用于当通信设备位于无线网络的覆盖区域中时与通信设备进行通信，以及处理单元，用于根据从接收到的信息获得覆盖区域内的通信设备的位置 应答器单元。

公开(公告)号：HU0101092A2

公开(公告)日：2001-07-30

申请号：HU0101092

申请日：1999-04-21

Applicant: IBM

Inventor： GFELLER FRITZ ,  HIRT WALTER ,  INGHAM BRIAN R

IPC: H04B10/11 ,  H04L25/02 ,  H04B10/10

Abstract: The present invention provides an apparatus and a method for improved connectivity in wireless optical networks. Therefore at least two or more receiving units are used which receive an infrared signal and convert it to a digital signal. The digital signals represent data in the form of frames whereby each frame comprises at least a data field and a header field containing a preamble. A selector determines a measure related to the signal-to-noise ratio of the preamble and compares the measures in order to select the best suited signal for further processing.

公开(公告)号：DE69411954D1

公开(公告)日：1998-08-27

申请号：DE69411954

申请日：1994-04-18

Applicant: IBM

Inventor： GFELLER FRITZ

IPC: G06F3/00 ,  C09K3/00 ,  G06F13/00 ,  H04B10/114 ,  H04B10/10

Abstract: PCT No. PCT/EP94/01196 Sec. 371 Date Sep. 3, 1996 Sec. 102(e) Date Sep. 3, 1996 PCT Filed Apr. 18, 1994 PCT Pub. No. WO95/28777 PCT Pub. Date Oct. 26, 1995The wireless optical (in particular infrared) communication system with at least one transmitter (75) and one receiver (76) comprises control means (77, 78), which dynamically adapt the data rate and/or the optical power of the transmitter in dependence of signal-to-noise ratio of the receiver. Due to this adjustment, optimized system performance is maintained even under the influence of ambient light which statistically changes the signal-to-noise ratio of the receiver. The best compromise between data rate, bit error rate and transmission range is dynamically determined. The control function is distributed between transmitting and receiving system unit. The control information is communicated via wireless optical communication.

公开(公告)号：AT168843T

公开(公告)日：1998-08-15

申请号：AT94914398

申请日：1994-04-18

Applicant: IBM

Inventor： GFELLER FRITZ

IPC: H04B10/10

公开(公告)号：DE2967024D1

公开(公告)日：1984-07-05

申请号：DE2967024

申请日：1979-11-06

Applicant: IBM

Inventor： BAPST URS HEINRICH ,  GFELLER FRITZ ,  VETTIGER PETER

IPC: G01J1/42 ,  G01J1/44 ,  G02F2/00 ,  G02F2/02 ,  G06K7/10 ,  H04B10/114 ,  G06K7/14 ,  G06F3/033 ,  H04B9/00

Abstract: An arrangement for separating disturbing ambient light from an optical data signal, comprising an interference filter (1), the passband of which matches the wavelength of the optical data signal, and further comprising two photodiodes which are so arranged that one photodiode receives the light (IS, IAT) transmitted through the interference filter, and that the other receives the reflected light (IAR). Adjusting means, e.g., in the form of a settable aperture (4) or an additional simple filter (5) are provided for adjusting the transmitted and reflected portions of the ambient light to each other. Output signal (S1, S2) of both photodiodes are subtracted from each other in compensation circuitry (6). This results in compensation of the ambient light components so that at the output a signal (SR) is available which depends only on the actual data signal (IS).

公开(公告)号：DE60143782D1

公开(公告)日：2011-02-17

申请号：DE60143782

申请日：2001-05-14

Applicant: IBM

Inventor： GFELLER FRITZ ,  HIRT WALTER

IPC: H04B14/02 ,  H04L25/49 ,  H04B7/08 ,  H04B10/10 ,  H04B14/04

公开(公告)号：CA2322685C

公开(公告)日：2004-10-26

申请号：CA2322685

申请日：1999-04-21

Applicant: IBM

Inventor： GFELLER FRITZ ,  HIRT WALTER ,  INGHAM BRIAN RICHARD

IPC: H04B10/11 ,  H04L25/02 ,  H04B10/10

Abstract: The present invention provides an apparatus and a method for improved connectivity in wireless optical networks. Therefore at least two or more receiving units are used which receive an infrared signal and convert it to a digital signal. The digital signals represent data in the form of frames whereby each frame comprises at least a data field and a header field containing a preamble. A selector determines a measure related to the signal-to-noise ratio of the preamble and compares the measures in order to select the best suited signal for further processing.

公开(公告)号：DE19717926B4

公开(公告)日：2004-02-05

申请号：DE19717926

申请日：1997-04-28

Applicant: VISHAY SEMICONDUCTOR GMBH ,  IBM

Inventor： SCHAIRER WERNER ,  ANGERSTEIN JOERG ,  GFELLER FRITZ ,  HIRT WALTER

IPC: G08C17/00 ,  H04B10/11 ,  H04B10/10 ,  G08C23/04 ,  H04B10/02 ,  H04B10/24