Patents Issued in March 20, 2003
  • Publication number: 20030053386
    Abstract: An optical disk device in which the laser light power for writing data onto an optical disk is optimized. Test data is written onto an optical disk while laser light power is varied and the laser light power is optimized based on the quality of replayed signals of the test data. The space value of the replayed signal of the test data is detected and, when the space value is a value which should not exist, it is judged that 3T mark period is missing or excessively written and the laser light power in which such a space value is obtained is removed from the candidates for the optimum laser light power. Also, jitter and error rate of the replayed signal are detected. Even when the jitter is at a desirable value, if the error rate is greater than or equal to a predetermined value, the laser light power in which such an error rate is obtained is removed from consideration as a possible optimum laser light power.
    Type: Application
    Filed: September 10, 2002
    Publication date: March 20, 2003
    Applicant: TEAC CORPORATION
    Inventor: Naoto Takeda
  • Publication number: 20030053387
    Abstract: A vibration quantity measuring apparatus and method, and a loop design method in which a vibration quantity generated in a focus and tracking loop is accurately measured to optimally design a focus and tracking loop of an optical disc drive. The vibration quantity measuring apparatus includes an error gain adjusting unit which adjusts an amplitude of a focus and tracking error which occurs where a disc rotates, so as to maintain the amplitude of the focus and tracking error constant, a loop gain adjusting unit which compares a closed loop phase of a focus and tracking loop and a predetermined reference closed loop phase, and maintains a constant gain of the focus and tracking loop to compensate for a gain difference of an actuator, and a measuring unit which calculates and outputs a vibration quantity using an error adjusted by the error gain adjusting unit and the loop gain adjusting unit, and an output of a controller which controls a focus and tracking of the disc.
    Type: Application
    Filed: August 29, 2002
    Publication date: March 20, 2003
    Applicant: SAMSUNG ELECTRONICS CO., LTD.
    Inventors: Moon-noh Lee, Won Kim, Sung-ro Go, Dong-jin Lee, Hyun-seok Yang, Hong-gul Jun
  • Publication number: 20030053388
    Abstract: A method of adjusting a condition for at least one of a recording operation and a reproducing operation includes the following steps. At least first and second asymmetry values is found. The first asymmetry value is defined based on a first signal combination selected from at least three signals different in cycle from each other. The second asymmetry value is defined based on a second signal combination selected from the at least three signals. The second signal combination is different from the first signal combination. The condition is set with reference to the at least first and second asymmetry values.
    Type: Application
    Filed: September 4, 2002
    Publication date: March 20, 2003
    Applicant: NEC CORPORATION
    Inventor: Masatsugu Ogawa
  • Publication number: 20030053389
    Abstract: An optical disc apparatus for recording synchronous information and data on an optical disc. The synchronous information recorded at the beginning of a frame is established to a mark in one frame in a plurality of frames. For example, the synchronous information of the mark and the synchronous information of a space are alternately established. In a frame, the synchronous information of the mark may be established, and in the subsequent frame, either the synchronous information of the mark or the synchronous information of the space may be selected so as to allow a DSV to be minimized. On the synchronous information of the mark, ROPC is executed for adjusting power of laser light.
    Type: Application
    Filed: September 10, 2002
    Publication date: March 20, 2003
    Applicant: TEAC CORPORATION
    Inventor: Akira Mashimo
  • Publication number: 20030053390
    Abstract: An optical disk physical has a recording region divided into zones, each zone including physical tracks adjacent to each other. An integer number of sectors, are provided in each physical track. The angular recording density is higher in the more outward zones such that the linear recording density is substantially constant throughout the recording region, and logical tracks are formed of a predetermined number of sectors, independent of the physical tracks. The conversion between the logical track and sector addresses read from the disk and the linear logical addresses supplied from a host device is easy. The addresses written in headers of the sectors in the logical track in which data are actually recorded, including substitute sectors used in place of defect sectors, are preferably consecutive to further facilitate the conversion between the logical track and sector addresses read from the disk and the linear logical addresses supplied from the host device.
    Type: Application
    Filed: October 4, 2002
    Publication date: March 20, 2003
    Applicant: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Kyosuke Yoshimoto, M. C. Rao, Hiroyuki Ohata, Kazuhiko Nakane, Teruo Furukawa, Junichi Kondo, Masafumi Ototake
  • Publication number: 20030053391
    Abstract: A recording/reproducing device for recording/reproducing information on/from an information disc, which is rotatable about an axis of rotation, by means of a pick-up device movable over the rotating information disc comprises:
    Type: Application
    Filed: September 6, 2002
    Publication date: March 20, 2003
    Inventors: Augustinus Laurentius Braun, Leonardus Petrus Maria Tielemans
  • Publication number: 20030053392
    Abstract: An optical pick-up device uses a holographic optical element that includes a holographic optical element, formed by combining a birefringence medium and an isotropy medium, for adjusting an optical route of a transmitted beam according to a polarizing direction and wavelength of an incident beam. The optical pick-up device has an objective lens for focusing the beam pass through the holographic optical element on an optical disk according to the wavelength of such beam.
    Type: Application
    Filed: November 1, 2001
    Publication date: March 20, 2003
    Applicant: LG Electronics Inc.
    Inventor: Seong Yun Jeong
  • Publication number: 20030053393
    Abstract: In the past there has been a problem that on a detection surface the influence of interference causes a defocusing signal to degrade, narrowing the range in which spherical aberration can be stably detected. Accordingly, a diffraction grating is used to focus the inner and outer sides of luminous flux on separate optical detectors before the optical flux is focused on an optical detector and defocusing signals are independently calculated to find the difference therebetween, thereby providing a spherical aberration signal. This makes it possible to detect spherical aberation signals more stably.
    Type: Application
    Filed: August 29, 2002
    Publication date: March 20, 2003
    Inventors: Takeshi Shimano, Takeshi Maeda, Hirofumi Sukeda
  • Publication number: 20030053394
    Abstract: An optical pickup includes a light source which emits first and second lights having different wavelengths for a first recording medium and a second recording medium having a relatively large thickness, respectively, an optical path changer which alters a traveling path of incident light, and an objective lens which focuses the first and second lights on the recording medium. While the light source emits the first light, a photodetector is adjusted to be aligned with the optical axis for the first recording medium. The light source and/or a sensing lens are adjusted in the direction of the optical axis, and the tilt of the objective lens is adjusted. Next, while the light source is operated to emit the second light, the light source is adjusted in a rotating direction. As such, an optical axis alignment is completed for the first and second recording media.
    Type: Application
    Filed: September 17, 2002
    Publication date: March 20, 2003
    Applicant: SAMSUNG ELECTRONICS CO., LTD.
    Inventors: Soo-han Park, Young-sun Park, Moon-whan Lee, Do-hoan Nam, Chun-seong Park
  • Publication number: 20030053395
    Abstract: An optical pickup head device includes a diffraction grating for generating zero-order diffracted light and at least first-order diffracted light and provides a tracking error signal with a DPP method. The diffraction grating includes grating patterns with a nonuniform period or phase. The size of the first-order diffracted light converged on an optical recording medium is larger in the direction parallel to a tangent to the track than in the direction perpendicular to the tangent. P1/P0>PW2/PW1 is established, where PW1 represents the power that is required to record information on the optical recording medium, PW2 represents the maximum power that allows information recorded on the optical recording medium to be reproduced without being erased, P0 represents the light amount of the zero-order diffracted light converged on the optical recording medium, and P1 represents the light amount of the at least first-order diffracted light converged on the optical recording medium.
    Type: Application
    Filed: September 4, 2002
    Publication date: March 20, 2003
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Shin-Ichi Kadowaki, Yoshiaki Komma, Kousei Sano
  • Publication number: 20030053396
    Abstract: An optical pickup apparatus for reading and recording information on recording media includes a semiconductor laser, a collimating lens, a half mirror, a reflecting mirror, and an objective lens. Further included therein are a super-resolution cutoff filter and an aperture control filter, one of which is appropriately selected and set right before the objective lens by a filter switching-over device. When reading the DVD, the super-resolution cutoff filter is set at the optical path, whereas when reading the CD, the aperture control filter is set thereat. The filter switching device is arranged separately from an actuator driving system having the objective lens integrally structured therewith.
    Type: Application
    Filed: September 16, 2002
    Publication date: March 20, 2003
    Applicant: Minebea Co., Ltd.
    Inventors: Mizuki Nakamura, Atsushi Kitamura, Kozo Matsumoto, Motoji Egawa
  • Publication number: 20030053397
    Abstract: In an optical head apparatus including a first light source for emitting a first light beam having a first wavelength, a second light source for emitting a second light beam having a second wavelength different from the first wavelength, an objective lens, a photodetector, and first and second optical combining/splitting elements, the first optical combining/splitting element receives the first light beam from the first light source to outgo most of the first light beam therefrom to the second optical combining/splitting element and receives the first and second light beams from the second optical combining/splitting element to outgo most of the first and second light beams therefrom to the photodetector.
    Type: Application
    Filed: September 16, 2002
    Publication date: March 20, 2003
    Applicant: NEC Corporation
    Inventors: Ryuichi Katayama, Eiichi Ueda, Taku Tsuboi
  • Publication number: 20030053398
    Abstract: A laser beam emitted from a laser diode and having a wavelength of 780 nm is S-polarized. A polarization plane rotating means (&lgr;/4 phase plate) is disposed between a super-resolution cut-off filter comprising a polarizing filter film and an objective lens. When reading on DVD, the objective lens, the polarization plane rotating means and the super-resolution cut-off filter in combination are set to the optical path. The S-polarized laser beam is focused to a micro spot diameter by super-resolution effects by the super-resolution cut-off filter together with the objective lens. Also, the S-polarized laser beam reflected at a disk and traveling backward along the incoming optical path is converted into a P-polarized laser beam while passing backward through the polarization plane rotating means. The P-polarized laser beam passes through the super-resolution cut-off filter without loss is received by a photo-detector.
    Type: Application
    Filed: September 12, 2002
    Publication date: March 20, 2003
    Applicant: MINEBEA CO., LTD.
    Inventors: Mizuki Nakamura, Atsushi Kitamura, Kozo Matsumoto, Motoji Egawa
  • Publication number: 20030053399
    Abstract: A high-density information storage apparatus using electron emission and methods of writing, reading and erasing information using the same are provided. The high-density information storage apparatus includes a lower electrode, a photoconductive layer and a recording medium sequentially provided on the lower electrode, a conductive layer converting unit for making the photoconductive layer conductive, a data write and read unit for writing data to the recording medium or reading data from the recording medium, a data loss preventing unit for preventing loss of data during data write and read operations, and a power supply connected to the lower electrode and the data write and read unit, for supplying voltage necessary for reading and writing data.
    Type: Application
    Filed: March 6, 2002
    Publication date: March 20, 2003
    Applicant: Samsung Electronics Co., Ltd.
    Inventors: In-kyeong Yoo, Won-bong Choi, Byong-man Kim
  • Publication number: 20030053400
    Abstract: A dielectric information apparatus is provided with a plurality of electrodes (14) for recording information in a small area of a dielectric substance (12) and an earthed electrode (13). The electrodes (14, 13) are placed such that the dielectric substance (12) is sandwiched between the electrodes (14) and the electrode (13). The dielectric information apparatus reads out the information recorded in the small area of a dielectric thin film (12) by applying alternating current signals to the first electrodes (14). The polarization direction of the small area and the direction of an applied electric field decide the dielectric constant of the small area, and the oscillation frequency of an oscillator 20 is determined by a capacitance Cs corresponding to the dielectric constant. An oscillation signal of the oscillator 20 is demodulated at a FM demodulator 21, and the information is detected from the demodulated signal at a signal detector 22.
    Type: Application
    Filed: September 10, 2002
    Publication date: March 20, 2003
    Inventors: Yasuo Cho, Atsushi Onoe
  • Publication number: 20030053401
    Abstract: An optical disk clamper holding mechanism that holds an optical disk clamper includes a surrounding unit, a flange unit, a rib that touches, when the optical disk clamper moves in the direction of the flange opening, a rim portion of an upper flange unit of the optical disk clamper, the rib protruding inwardly at a position opposite to the flange opening. Since the range of clearance in which the optical disk clamper can move in the optical disk clamper holding mechanism is restricted, the optical disk clamper always fits in the turntable normally and consequently, always clamps the optical disk normally.
    Type: Application
    Filed: September 13, 2002
    Publication date: March 20, 2003
    Inventors: Manabu Ogasawara, Yoshihiro Okano, Yoshihiro Shimazu, Masahiko Sakaguchi, Hisataka Usui
  • Publication number: 20030053402
    Abstract: Disclosed is a disk clamper for cooperating with a disk table to chuck a disk-type recording medium, comprising: a support section disposed in an opposing relationship to the disk table; and a stabilizer supported on the support section for movement toward and away from the disk table; wherein, when the disk-type recording medium is chucked, the stabilizer is attracted to the disk table with the disk-type recording medium interposed therebetween, but when the disk-type recording medium is not chucked, the stabilizer is attracted to the support section. Accordingly, chucking operation in an assured manner can be realized.
    Type: Application
    Filed: November 1, 2002
    Publication date: March 20, 2003
    Applicant: Sony Corporation
    Inventors: Akihisa Inatani, Kumi Koyama, Takayuki Kaneko, Harutoshi Yoshimura, Kenji Kawakami, Akiomi Suzuki, Masako Sudo, Yutaka Sato, Shigeru Saegusa, Sakae Washikawa
  • Publication number: 20030053403
    Abstract: In the recordable type multilayer optical disk, interlayer crosstalk is large in an ID or address data region, a boundary region between a recorded part and an unrecorded part, etc. Locations of an information recording unit region and of ID or address data of adjacent plural tracks on a recording medium are configured so as to be shifted in the circumferential direction by 5 &mgr;m or more. Since an effect from a layer that is not selected can be remarkably reduced in the multilayer optical disk, multilayer recording/reproducing can be realized in the recordable type optical disk. Moreover, since pieces of the ID or address data do not center at the same position in reference to the circumferential direction, the effect of distortion that is generated on the disk substrate and the recording layer at the time of optical disk formation or multiple overwriting can be minimized, and design and fabrication tolerances of the optical disk are extended, and as a result the media can be provided with a low cost.
    Type: Application
    Filed: August 10, 2001
    Publication date: March 20, 2003
    Inventors: Harukazu Miyamoto, Takeshi Maeda, Toshimichi Shintani, Takahiro Kurokawa, Tetsuo Ariyoshi, Hirofumi Sukeda
  • Publication number: 20030053404
    Abstract: An information recording medium including a substrate having a tiny pattern of serial groove portion and land portion alternately formed in parallel, a recording layer composed of recording material formed on the tiny pattern of the substrate, and a transparent layer formed on the recording layer, having the thickness of 0.05 to 0.4 mm, wherein the tiny pattern is formed under condition of P≦&lgr;/NA that P is a pitch of the groove portion and the land portion, &lgr; is a wavelength of a laser light for reproducing information from the information recording medium, NA is a numerical aperture of an objective lens for outputting the laser light for reproducing information from the information recording medium, and a reference clock is recorded windingly in the land portion as a sine waveform.
    Type: Application
    Filed: March 21, 2002
    Publication date: March 20, 2003
    Inventor: Tetsuya Kondo
  • Publication number: 20030053405
    Abstract: Plural grooves or lands formed in an information recording carrier include at least a wobbling region and data is recorded wobblingly in this wobbling region by frequency shift modulation while recorded digitally with a single or multiple waves as a channel bit.
    Type: Application
    Filed: September 18, 2002
    Publication date: March 20, 2003
    Inventor: Tetsuya Kondo
  • Publication number: 20030053406
    Abstract: A recording/reproducing medium having grooves, a land formed between the grooves, and land prepits formed on the land in which each of said land prepits has a most optimum design condition where a ratio (LLP Level/offset) between a voltage amplitude (LLP Level) of a land prepit detection signal and an offset level (offset) of an RF signal becomes more than about or where an amplitude change of an RF signal through the land prepit becomes minimum. The recording/reproducing medium can be one of a DVD-R and a DVD-RW.
    Type: Application
    Filed: October 21, 2002
    Publication date: March 20, 2003
    Applicant: PIONEER CORPORATION
    Inventors: Eiji Muramatsu, Masahiro Kato, Makoto Sato
  • Publication number: 20030053407
    Abstract: An optical recording medium includes a substrate having groove and land areas, in which address pits having substantially the same depth and which are formed deeper than the groove area are provided. By thus forming the address pits deeper than the groove area, address information can be reproduced accurately, and the optical recording medium can readily be manufactured by making the address pits which are respectively formed in the groove and land areas to have substantially the same depth.
    Type: Application
    Filed: October 25, 2002
    Publication date: March 20, 2003
    Inventors: Junji Hirokane, Noboru Iwata
  • Publication number: 20030053408
    Abstract: A disk cartridge is provided. The disk cartridge includes a case for containing a disk and a transparent window installed to seal the case. An external light accesses the disk through the transparent window of the disk cartridge. However, foreign matter such as dust is prevented from entering the disk cartridge.
    Type: Application
    Filed: December 31, 2001
    Publication date: March 20, 2003
    Applicant: Samsung Electronics Co., Ltd.
    Inventors: Gyu-chan Jun, Soon-kyo Hong, Dong-seob Jang, Young-min Cheong, Du-il Kim
  • Publication number: 20030053409
    Abstract: A disc cartridge includes: a cartridge body including a disc storage portion storing a disc, having first and second sides, therein so that the disc is rotatable there and that the first side is exposed and chucking and head opening formed on the bottom of the storage portion so as to get the disc chucked externally and allow a read/write head to access the second side, respectively; a shutter supported, and movable with respect to the cartridge body, between the second side of the disc and the bottom of the disc storage portion so as to expose or cover the chucking and head openings and defining a hole under a center hole of the disc while the shutter is closed; and a disc holder provided for the shutter and pressing the disc against the shutter and holding it thereon while the chucking and head openings are covered with the shutter.
    Type: Application
    Filed: July 2, 2002
    Publication date: March 20, 2003
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Hironori Okazawa, Teruyuki Takizawa, Yoshito Saji, Kuniko Nakata
  • Publication number: 20030053410
    Abstract: A multi-carrier communications system with a programmable interleaver and de-interleaver that can change the interleaving rate for data transmitted and received in the communications system is presented. The programmable interleaver and de-interleaver permits a level of flexibility in determining the immunity of the communications system to errors and sources of interference. The multi-carrier communications system is able to vary the interleaving rate based on input from a user or from data that it maintains from actual network performance. The multi-carrier communications system can change the interleaving rate during the initial installation of the multi-carrier communications system or whenever the system is reset or restarted or on any individual transmission unit.
    Type: Application
    Filed: September 14, 2001
    Publication date: March 20, 2003
    Inventors: Richard Williams, Srikanth Gummadi
  • Publication number: 20030053411
    Abstract: A technique includes receiving a signal that indicates a modulated symbol during a given time slice of the signal. Sliding window frequency transformations of the signal are performed, and each sliding window transformation is associated with a different time interval of the signal. One of the time intervals is selected to correspond to the time slice. The result of the frequency transformation associated with the selected time interval is used to obtain an indication of the demodulated symbol.
    Type: Application
    Filed: August 30, 2001
    Publication date: March 20, 2003
    Inventor: Eric A. Jacobsen
  • Publication number: 20030053412
    Abstract: In order to improve upon a degradation in performances due to inter-carrier interference without loss of transmission efficiency, antennas provided on a mobile body are made directional antennas. An antenna selection unit selects a directional antenna in such a manner that Doppler shift that is caused by movement of the mobile body will keep a constant sign that is positive or negative, a fading-variation calculation unit calculates the average value of fading variation on each path of a multipath environment, and a fading-variation compensation unit compensates the multipath fading variation based upon the average value.
    Type: Application
    Filed: April 9, 2002
    Publication date: March 20, 2003
    Inventors: Makoto Yoshida, Yoshinori Tanaka
  • Publication number: 20030053413
    Abstract: A radio transmission system is configured to, on the occasion of radio transmission of information between a transmitter and a receiver, perform the radio transmission of information using an orthogonal frequency and code division multiplexing transmission scheme of parallelly transmitting identical information by a plurality of sub-carriers. The radio transmission system has a spreading factor variable control transmitting device for parallelly converting information channel-coded at the transmitter, according to symbols transmitted simultaneously, and for spreading a sequence of parallelized symbols in at least one of a frequency direction and a time direction by a spreading code sequence of a designated spreading factor.
    Type: Application
    Filed: August 30, 2002
    Publication date: March 20, 2003
    Applicant: NTT DoCoMo, Inc.
    Inventors: Mamoru Sawahashi, Hiroyuki Atarashi, Sadayuki Abeta, Noriyuki Maeda
  • Publication number: 20030053414
    Abstract: With respect to a router in a backup path in an MPLS network adopting a label stack method, it is an object of the present invention to achieve the same quality-guarantee control as the one performed in a current path. In a packet transfer device accommodating first and second output lines, when the first line has a fault, upon a first packet being received, communication quality information in a header of the first packet is copied. Further, a first header containing the copied priority information and a new label is added to the first packet, and a packet to which the first packet is added is outputted to a second output line. When a second packet is received, communication quality information in a header of the second packet is copied, a second header containing the copied priority information and the new label is added to the second packet, and a packet to which the second packet is added is outputted to the second output line.
    Type: Application
    Filed: June 19, 2002
    Publication date: March 20, 2003
    Applicant: Hitachi, Ltd.
    Inventors: Shinichi Akahane, Kazuo Sugai
  • Publication number: 20030053415
    Abstract: In source routed or hop-by-hop routed protocol communication networks, when congestion is detected at a certain network element, a notification message is sent to nodes. The nodes keep track of congestion condition and generally have knowledge of the congestion, thereby allowing them to make more intelligent routing decisions, i.e., rate controlling messages, routing traffic around congestion, regulating admission at the edge of the network. The intelligent routing decision is based on the congestion condition indicated by a restriction level which is periodically and dynamically updated.
    Type: Application
    Filed: July 31, 2002
    Publication date: March 20, 2003
    Applicant: Alcatel Canada Inc.
    Inventors: Ram Balakrishnan, Mustapha Aissaoui, Mudashiru Busari, John Coffell, Shawn McAllister, Peter Roberts
  • Publication number: 20030053416
    Abstract: A method and system including an improved generalized reference decoder that operates according to any number of sets of rate and buffer parameters for a given bit stream. Each set characterizes a leaky bucket model and contains three parameters representing the transmission bit rate, buffer size, and initial decoder buffer fullness. An encoder provides at least two sets of these parameters, whereby the decoder selects one or interpolates between them to operate at any desired peak bit rate, buffer size or delay. The generalized reference decoder may select the smallest buffer size and corresponding delay that decodes the bit stream without buffer underflow or overflow, or alternatively may select and operate at the minimum required peak transmission rate, or something between both. In practice, the buffer size, delay and/or the peak transmission rate can be reduced by significant factors, and/or the signal-to-noise ratio (SNR) can be increased.
    Type: Application
    Filed: September 19, 2001
    Publication date: March 20, 2003
    Applicant: Microsoft Corporation
    Inventors: Jordi Ribas-Corbera, Philip A. Chou
  • Publication number: 20030053417
    Abstract: A rotator switch includes active and redundant tandem buffers used to switch information units through the switch. The tandem buffers are interconnected to inputs and outputs by way of commutators. Information provided to one or more of the active buffers is provided to a redundant buffer. If an active tandem buffer fails, the switch may use the redundant buffer in place of the failed active buffer. A further rotator switch is formed using a plurality of switching blocks. Each switching block includes its own set of tandem buffers, and ingress and egress commutators to interconnect the tandem buffers to inputs and outputs. The plurality of switching blocks is interconnected using additional commutators. At least one of these switching blocks is redundant and is provided with information provided to an active switching block. In the event of failure of an active block, the switch may use a redundant switching block in place of the failed or replaced active block.
    Type: Application
    Filed: September 18, 2001
    Publication date: March 20, 2003
    Applicant: NORTEL NETWORKS LIMITED
    Inventors: Ernst A. Munter, Delfin Y. Montuno, James Aweya
  • Publication number: 20030053418
    Abstract: A wireless communication network with improved performance and a method and controller for controlling data rate in the network are provided. The invention provides a feedforward approach to data rate control in wireless networks. The invention is based on designing an optimal, but non-causal, controller and its subsequent “causification,” which results in a practical, implementable controller, driven by an estimate of the bit error probability. This controller leads to a minimum 5%-85% increase in average throughput without additional power utilization, as compared with fixed data rate operation.
    Type: Application
    Filed: June 19, 2002
    Publication date: March 20, 2003
    Inventors: Pierre T. Kabamba, Semyon M. Meerkov, Wayne E. Stark, Choon Yik Tang
  • Publication number: 20030053419
    Abstract: In a packet communication quality measurement method in which two quality measurement devices connected via a packet communication network exchange a probe packet via the packet communication network and the packet communication quality is calculated based on the transmission/reception status of the probe packet, probe packets are intermittently transmitted from one quality measurement device to the other quality measurement device via the packet communication network at a predetermined interval, and received by the other quality measurement device. The communication quality of each probe packet is calculated based on the transmission/reception status of the probe packet. The communication quality is weighted in accordance with the number of packets flowing in a desired measurement direction along the path which connects the quality measurement devices at an interval between transmission of a previous probe packet and transmission of the probe packet.
    Type: Application
    Filed: August 21, 2002
    Publication date: March 20, 2003
    Inventors: Toshiyuki Kanazawa, Keisuke Ishibashi, Masaki Aida
  • Publication number: 20030053420
    Abstract: Methods and apparatus for monitoring the performance of services provided over a network (2). The methods and apparatus make use of the computing power provided at the communications units (1) used by users to access the services. Activity instigated by users both directly and indirectly are monitored and/or reproduced at each communications unit (1). Information gathered in the monitoring processes is sent to a central unit (4) for further processing. Typically the services are accessed via the World Wide Web and part of the apparatus is controlled by a Java/Javascript applet running on a communications unit (1).
    Type: Application
    Filed: September 16, 2002
    Publication date: March 20, 2003
    Inventors: Malcolm J. Duckett, Jeremy A. C. Barker, Ruys A. Newman
  • Publication number: 20030053421
    Abstract: There is provided a packet transfer apparatus with a function of performing packet request for a server on a network in the state where stealth characteristics are secured. The apparatus performs packet request using address information of the server on the network. Further, the apparatus identifies and acquires a packet requested by the apparatus itself among packets received from the server on the network.
    Type: Application
    Filed: August 28, 2002
    Publication date: March 20, 2003
    Applicant: Kabushiki Kaisha Toshiba.
    Inventor: Masahiko Yoshimura
  • Publication number: 20030053422
    Abstract: In a switch supporting a multiple spanning tree protocol and a bridged network formed of such a switch, the switch includes a default spanning tree in a multiple spanning tree, transmits, upon receipt of a frame having an individual destination address from a terminal side, an inquiry frame to a destination terminal of the individual destination address through the default spanning tree, transmits inquiry response frames to all of the spanning trees in the multiple spanning tree if the destination terminal is connected to the switch, and selects an optimum spanning tree based on information in the inquiry response frames from all of the spanning trees.
    Type: Application
    Filed: January 29, 2002
    Publication date: March 20, 2003
    Inventor: Michiko Ambe
  • Publication number: 20030053423
    Abstract: A method and a telecommunications system for interchanging messages and information during a telephone conference, with the telephone conference taking place via a telephone network and the telephone conference being assigned a code which can be predetermined, and from which a password is derived which allows the subscribers to the telephone conference access to a communication platform which is based on a data network, for the purpose of interchanging data during the telephone conference.
    Type: Application
    Filed: April 9, 2002
    Publication date: March 20, 2003
    Inventor: Jordi Mateu
  • Publication number: 20030053424
    Abstract: A wireless hybrid network consisting at least one satellite 118 and a plurality mobile ad hoc nodes 104. The nodes 104 are assumed to be clustered into mobile groups 102 within the footprint of the satellite 118, and the objective is to enable reliable communications between the various nodes 104. At least one relatively powerful gateway 110, also mobile, is deployed for each cluster 102 of nodes to facilitate communication with a LEO or GEO satellite 118. The environment is characterized by the presence of terrestrial barriers 100 or other severe channel impairments. One of the goals of the invention is to provide a mechanism by which a mobile gateway 112 can change its position or define its trajectory based on the position and loading of the nodes 104 in an ad hoc network, so as to optimize certain pre-defined performance criterion, such as power, overhead, throughput.
    Type: Application
    Filed: August 7, 2001
    Publication date: March 20, 2003
    Inventors: Srikanth Krishnamurthy, Mohin Ahmed, George D. Kondylis
  • Publication number: 20030053425
    Abstract: A computer device, according to the present invention, includes: a power source judging means for judging whether power is supplied from an AC power source to the computer device capable of connecting with a wireless communications module which transmits and receives data to/from an access point; and a control means for controlling the timing of measuring the strength of connection with the above described access point based on judgment by the above described power source judging means. Therefore, by setting the timing of measuring the strength of connection with the access point based on whether or not the computer device is used at an almost fixed location, which in turn is judged by distinguishing the type of power source, it is possible to change the amounts of data transmitted and received by the wireless communications module.
    Type: Application
    Filed: August 23, 2002
    Publication date: March 20, 2003
    Applicant: International Business Machines Corporation
    Inventors: Kozo Matsunaga, Masaharu Itoh, Kazuo Fujii
  • Publication number: 20030053426
    Abstract: An uplink channel transmission power control method is provided for a CDMA mobile communication system performing one way communication. A base station measures the received level of data transmitted from each mobile terminal at each channel, and generates a transmission power control signal of each uplink traffic channel. The generated transmission power control signals are multiplexed, and the multiplexed common transmission power control signal is transmitted to all mobile terminals by using the common channel shared by the mobile terminals. Each mobile terminal derives the transmission power control signal of the uplink traffic channel used by the terminal, from the received common transmission power control signal, and controls the transmission power of a data packet.
    Type: Application
    Filed: October 3, 2002
    Publication date: March 20, 2003
    Applicant: Hitachi, Ltd.
    Inventors: Katsuhiko Tsunehara, Takashi Yano, Nobukazu Doi, Takaki Uta, Keiji Hasegawa
  • Publication number: 20030053427
    Abstract: A mobile terminal transmits an extended packet including address-range information and a no-operation designator. After a router receives the extended packet including the no-operation designator, it transfers the received packet by performing normal routing. After a server receives the transferred packet, it transmits a response packet in the form of an extended packet including a destination address which is the transmitter's address of the received packet, the address-range information, and an operation designator. After the router receives the extended packet including the operation designator in an intranet to which the mobile terminal belongs, it transfers the received packet through at least one network interface corresponding to the address range designated by the address-range information. The mobile terminal processes the received packet when its destination address indicates the mobile terminal.
    Type: Application
    Filed: September 17, 2002
    Publication date: March 20, 2003
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Mitsuru Kanda, Naoki Esaka, Satoshi Ozaki
  • Publication number: 20030053428
    Abstract: A verification system and method for packet call processing of a mobile telephone. Each IP address is assigned to a terminal, a packet service simulator and the mobile telephone. The packet service simulator simulates a control signal of UTRAN necessary for the mobile telephone and connects data traffic to an Internet after a packet call establishment. The packet service simulator transmits an IP packet generated from the terminal to its Ethernet address, receives a packet for the terminal and transmits it to the mobile telephone. For this, the packet service simulator responds to the terminal's ARP request.
    Type: Application
    Filed: December 20, 2001
    Publication date: March 20, 2003
    Inventors: Ae-Soon Park, Nak-Woon Sung
  • Publication number: 20030053429
    Abstract: There is provided a method for performing an inter-packet data service node (PDSN) soft handoff. The method is implemented by setting up a channel passing through a target base station controller (T-BSC), a source base station controller (S-BSC) and a source-PDSN (S-PDSN) by establishing a direct channel link between the S-BSC and the T-BSC in an active packet session mode, performing a handoff between the S-BSC, the T-BSC and a mobile station (MS), transmitting or receiving user packet data exchanged between the MS, and the S-BSC and the T-BSC to or from the S-PDSN through the established channel link and sending or receiving user packet data exchanged between the MS and the T-BSC to or from the S-PDSN through the established channel link when the handoff is completed.
    Type: Application
    Filed: December 27, 2001
    Publication date: March 20, 2003
    Inventors: Sang-Ho Choi, Kyung-Sik Kim, Dong-Jin Shin
  • Publication number: 20030053430
    Abstract: There is provided a method for performing an inter-packet data service node (PDSN) hard handoff. The method is implemented by setting up a channel link passing through a target base station controller (T-BSC), a source base station controller (S-BSC), a source packet control function (S-PCF) and a source-PDSN (S-PDSN) by establishing a channel link between the S-BSC and the T-BSC via a mobile station center (MSC) in an active packet session mode, performing the hard handoff between the S-BSC, the T-BSC and a mobile station (MS) and transmitting or receiving user packet data exchanged between the MS and the T-BSC through the established channel link to or from the S-PDSN in case the hard handoff is completed.
    Type: Application
    Filed: December 27, 2001
    Publication date: March 20, 2003
    Inventors: Sang-Ho Choi, Kyung-Sik Kim, Sun-Bae Lim
  • Publication number: 20030053431
    Abstract: The present invention relates to a method for performing a handoff process in a packet data network. For doing so, the method provides a Mobile Switching Center (MSC) for receiving a handoff required message from a source Base Station (BS). The MSC further generates and sends to a target BS a handoff request message based on the received handoff required message. The target BS receives the handoff request message; and sends a handoff request acknowledge message including a Packet Zone identification (PZID) parameter for identifying a target Packet Core Function (PCF).
    Type: Application
    Filed: September 10, 2002
    Publication date: March 20, 2003
    Inventor: Lila Madour
  • Publication number: 20030053432
    Abstract: A method and apparatus for transmitting digital data in a cellular environment. Adjacent cells of the cellular system are prevented from simultaneously transmitting data. Because the noise from transmissions of adjacent cells is a primary source of interference, the transmission rate of power limited base stations can be dramatically increased when the noise from adjacent cells is eliminated. The transmissions to each subscriber station are made at a fixed transmission power level. However, the data rate of transmitted signals differs from one subscriber station to another depending the path loss differences. In a first exemplary embodiment, the data rate of transmissions to a subscriber station is determined by selecting an encoding rate for the transmitted signal while holding the symbol rate constant.
    Type: Application
    Filed: October 11, 2002
    Publication date: March 20, 2003
    Applicant: QUALCOMM Incorporated
    Inventor: Ephraim Zehavi
  • Publication number: 20030053433
    Abstract: A system and method for communicating between a vehicle data unit, such as a car computer, and a remote data unit, such as a home personal computer, commercial server, or another vehicle data unit, via a short range, high bandwidth communication link, such as via a wireless local area network (WLAN).
    Type: Application
    Filed: September 19, 2001
    Publication date: March 20, 2003
    Inventor: Anthony L. Chun
  • Publication number: 20030053434
    Abstract: A wireless subscriber terminal (ST) for use with IP push-to-talk (IPP2T) service using a wireless local area network (WLAN) operating in a plurality of modes, including a mobile terminal having an ability to communicate over the air to a wireless Access Point (AP), the mobile terminal further programmable to use conventional WLAN protocols, and a method for operating the wireless terminal are described.
    Type: Application
    Filed: July 26, 2002
    Publication date: March 20, 2003
    Applicant: AT&T Corp.
    Inventors: Albert T. Chow, Robert Raymond Miller, John F. Murray, Christopher W. Rice
  • Publication number: 20030053435
    Abstract: In a transmission scheme wherein multi-slot packet transmissions to a remote station can be terminated by an acknowledgment signal from the remote station, code symbols can be efficiently packed over the multi-slot packet so that the remote station can easily decode the data payload of the multi-slot packet by decoding only a portion of the multi-slot packet. Hence, the remote station can signal for the early termination of the multi-slot packet transmission, which thereby increases the data throughput of the system.
    Type: Application
    Filed: May 22, 2001
    Publication date: March 20, 2003
    Inventors: Nagabhushana Sindhushayana, Peter J. Black