Abstract: A method and apparatus for managing a session key for allowing a mobile terminal to access a wireless local area network (WLAN). The invention provides for establishing a first secure channel between an access point and a virtual operator, and suggesting a session key to the virtual operator from the access point. A second secure channel is established between the virtual operator and a user, and the session key is sent to the user via the second secure channel upon successful user authentication. The mobile terminal accesses the WLAN using the session key.

Abstract: Playback durability of a writable optical disk is ensured. A method of controlling a playback condition includes continuously irradiating an optical disk with a laser beam having a power level lower than a mark formation level and detecting a change of a state of a signal caused by a return light from the optical disk, and setting a playback condition for the optical disk according to the change of the state of the signal. The playback durability of the optical disk can be ensured by adaptively controlling the playback condition as stated above.

Abstract: This invention concerns a process and a system for providing location information for a wireless unit in a wireless network to a location-based service provider, using a data network. In particular, the location information is provided to the location-based service provider without necessarily providing the identity of wireless unit, e.g., a subscriber's wireless identification number, to the service provider. In this regard, a subscriber's identification number may be hidden from the positioning service provider via a process in which an alias is used instead of the subscriber's normal identity. The subscriber's number may further be concealed from the service provider via a process wherein encrypted information is used instead of the subscriber's normal identity.

Abstract: An information recording and/or reproducing apparatus includes an optical head, an analog signal processor, an analog/digital converter, a controller and a digital/analog converter. The optical head is used for emitting a light beam on a medium and receiving a reflected light beam from the medium. The analog signal processor is used for processing the reflected light beam to obtain a first analog signal. The analog/digital converter is used for converting the first analog signal into a digital signal. The controller is used for applying a low-pass filtering operation on the digital signal to obtain a digital controlling signal. The digital/analog converter is used for converting the digital controlling signal into a second analog signal. The second analog signal is transmitted to the optical head for correcting a tilt between the light beam and the medium.

Abstract: A method for evaluating a read signal obtained by irradiating a medium with a laser beam through an objective lens and reading data from the reflected laser beam by a PRML detection method is provided. The method includes: a sampling step of sampling the data obtained from the reflected laser beam at clock timings to obtain sampled values; and a step of, when a constraint length of a PR class in the PRML detection method is an even number, computing an intermediate sampled value for evaluation using at least adjacent two of the sampled values arranged in the order sampled at the clock timings. The provided method is an objective evaluation method when the PRML detection method is used, whereby the selection of a recording medium and a reading apparatus is facilitated.

Abstract: A nomadic server and a related system provides seamless roaming for a mobile communication device between different types of wireless networks, such as WiFi and cellular networks for voice, data and video communication. Use of the nomadic server enables a combination of WiFi and cellular networks for providing access to the cellular phones and make use of the VOIP networks for switching the calls wherever possible. The nomadic server is a telephone communication processing and switching server that will “hold” the present, in-progress telephone communications without dropping, while roaming without losing the present, in-progress communication. For example, a telephone communication can be seamlessly switching between VOIP and cellular telephone networks using the nomadic server. Nomadic server resources interface with the VOIP and cellular network switches to provide the hand-off between networks.

Abstract: One general embodiment of the present invention is a magnetic read head including a magnetoresistive sensor where sense current flows in a stacking direction of the magnetoresistive sensor, i.e., perpendicular to the plane of the layers of the head. The magnetoresistive sensor comprises a free layer having a magnetization direction that is affected by external magnetic fields and includes a Heusler alloy layer and a Co-based amorphous metal layer, a fixed layer which is stacked with the free layer and has a fixed magnetization direction, and a non-magnetic intermediate layer between the free layer and the fixed layer.

Abstract: There is provided, according to the present invention, a reproducing device capable of preventing illegal duplication and reproduction, as well as of reproducing content without degrading the quality of the audio and visual contents. The reproducing device (100) comprises a first storage area (110), in which data is stored, using file system which is not supported by operating system of the reproducing device, an interface part (120) supporting the file system which the first storage area uses, accepting only reproducing request, reading out and supplying the data stored in the first storage area, wherein the reading out and supplying operations are hidden, and a reproducing part (132) reproducing the data supplied by the interface part.

Abstract: To provide an optical disc device 1, and similar, equipped with a new mechanism to reduce laser light noise due to optical feedback. In an optical disc device 1 in which a laser diode is driven by a high frequency modulation method, optical feedback is returned to the laser diode at a timing at which the phase of the injected carrier density is within one of the following ranges: (1) equal to or greater than the peak phase of the injected carrier density of the laser diode, and equal to or less than the peak phase of the injected carrier density of the laser diode plus 3?/8 (radians); or (2) equal to or greater than the peak phase of the injected carrier density of the laser diode plus 9?/8 (radians), and equal to or less than the peak phase of the injected carrier density of the laser diode plus 2? (radians).

Abstract: Frequency response is characterized for mechanical components of a multirate system operating in a closed-loop environment. A disturbance is injected at the frequency of interest and at each of the alias frequencies thereof as an input into the multirate system, and a matrix equation composed of resulting measurements of the response of the multirate system is solved to compute the frequency response at the frequency of interest and at each of the alias frequencies. The resulting frequency response can be used to synthesize the transfer function of the entire system, which allows simulation and evaluation of the relative performance of multiple controller designs without the need for further frequency response measurements.

Abstract: This optical disk device includes an examination means which examines a first physical characteristic of an optical disk, and a servo means which starts servo control based upon that first physical characteristic. This optical disk device includes a read means which incorporates the examination means, and which reads type information from the optical disk under that servo control based upon the first physical characteristic. This optical disk device includes a control means which decides whether or not a second physical characteristic of the optical disk, which is determined as a standard for the type of type information read, and the first physical characteristic, agree with one another. And, if the control means has decided that these two physical characteristics do not agree with one another, it commands the read means to read replay data from the optical disk, under that servo control based upon the first physical characteristic.

Abstract: A read/write head for use with bit-patterned media detects write synchronization errors between a write clock and the bit-patterned media. In particular, the read/write head writes data to the bit-patterned media using a write clock. The data is then read from the bit-patterned media and used to detect write synchronization errors between the write clock and the location of bit-islands on the bit-patterned media. Based on detected write synchronization errors, the phase associated with the write clock is modified to align the write clock with the location of bit-islands on the bit-patterned media.

Abstract: A method of self servo-writing servo information to a plurality of disk surfaces in a disk drive that includes writing servo information to a plurality of disk surfaces in a first direction, writing servo information to a plurality of disk surfaces in a second direction, and determining an amount of overlap to be written on a reference surface with the reference head that will produce an overlap of servo information on each of the surfaces in the disk drive to which servo information is to be written. The method also includes switching to different tables when seeking across the overlap or border areas.

Abstract: A data recording and reproducing device includes: a light emitting element that generates light and emits the light toward an optical recording medium; a light emission control section that feedback-controls an emitted light quantity from the light emitting element; a light attenuating drive section that includes a light attenuating section, and inserts the light attenuating section into an emission path of the light when reproducing data from the optical recording medium and retracts the light attenuating section from the emission path when recording data onto the optical recording medium; and a shock detecting section that detects a shock of a magnitude causing the light attenuating drive section to switch between the insertion and retraction. When the shock detecting section detects the shock during data recording, the light emission control section lowers a control target value of the emitted light quantity from a value set at the time of shock detection.

Abstract: Trial writing is made by recording waveform different from that used to record information in a disc. In the trial writing, particularly, the strategy having short cooling time or large cooling power is used to make recording, so that the jitter characteristic having clear difference between jitters in magnitude can be obtained to get stable calculated power. Thus, the recording quality can be ensured and user's convenience is increased.

Abstract: Methods for writing servo fields on a rotatable data storage disk using reference patterns on the data storage disk include generating a clock signal, reading a reference pattern signal from a surface of the disk, generating a phase error signal in response to a phase offset between the clock signal and the reference pattern signal, subtracting a timing control value from the phase error to provide an adjusted phase error, generating a frequency control signal in response to the adjusted phase error, and adjusting the frequency of the clock signal. The timing control value is generated in response to the phase error signal and the frequency control signal.

Abstract: An optical disc reproducing device that composes a composite reproducing apparatus in accordance with the present invention includes an optical disc detecting portion which detects inserting and ejecting of an optical disc. The optical disc reproducing device also includes an identification information obtaining portion which obtains identification information to uniquely identify the optical disc from a management information recorded area of the optical disc. The identification information obtaining portion reads out the identification information and outputs it to a display device when inserting of the optical disc is detected by the optical disc detecting portion. An identification information recording portion which is included in the display device stores the identification information in a memory portion when the identification information is output from the optical disc reproducing device.

Abstract: A video replay apparatus including a content storage device, a replay controller configured to control a replay of video material from the content storage device, the replay controller being configured to control the replay in accordance with metadata associated with the video material, the metadata defining an information content of the video material and defining an information event within the video material as a threshold change in the information content, and the replay controller is further configured to replay the video material with a pre-defined number of information events in a unit of time in a replayed sequence.

Abstract: With this invention, at least one of a video file containing video information, a still picture file containing still picture information, and an audio file containing audio information and a management file having management information on a control method of reproducing the information in the file are recorded on an information storage medium. This realizes a data structure that causes the recording and deleting places on the information storage medium to correspond spuriously to places on a single tape, such as a VTR tape. Use of the data structure provides users with an easy-to-use interface.

Abstract: With this invention, at least one of a video file containing video information, a still picture file containing still picture information, and an audio file containing audio information and a management file having management information on a control method of reproducing the information in the file are recorded on an information storage medium. This realizes a data structure that causes the recording and deleting places on the information storage medium to correspond spuriously to places on a single tape, such as a VTR tape. Use of the data structure provides users with an easy-to-use interface.