Abstract: An optical storage reconditioning module extends the life of re-writable optical medium, such as DVD+RW optical storage disks, by writing random information to recondition commonly used portions of the optical medium before re-writing information to those portions of the optical medium. For instance, a stored file system structure of an optical medium, such as a UDF random writable file system, is updated by reading to a buffer the structure from the optical medium, over writing the structure with random information recondition transitions between data points of the structure, updating the file system structure in the buffer and writing the updated file system structure over the random information.

Abstract: A method of recording digital information signals on a removable rewritable disc like recording medium, the method comprising recording user data on a logical area of the disc and, prior to removal of the disc out of a recording/reproducing apparatus, finalizing the disc with a lead-in and lead-out area comprising predefined medium format data. A general purpose area within the logical area for other use than recording of user data, is being reserved. Such as use may be for example defect management. Further the method involves interrupting recording a lead-in area or a lead-out area at predefined splice points whenever a request for user data is made.

Abstract: A control information generating circuit uses linear velocity information at a recording/reproduction position on an optical disc, which is obtained from an information recording medium by a synchronous signal cycle counter, and revolution number information, which is obtained from a rotation mechanism by a cycle counter of a frequency generator, to generate a piece of rotation control information, and the resultant information is supplied to a motor driving circuit. A variation detecting circuit generates a linear velocity abnormality detecting signal based on an abnormality detection result obtained by a division circuit, thereby preventing an abnormal operation of a spindle motor. With such a structure, switching of the control mode between CAV control mode and CLV control mode in a continuous recording/reproduction operation on an optical disc, or the like, is smoothly performed using one pierce of rotation control information.

Abstract: An information recording medium includes a data area for recording data; and a drive information area for recording at least one piece of drive information. The data area is divided into a plurality of segmented areas in a radial direction of the information recording medium. Each at least one piece of drive information includes a recording and reproduction condition corresponding to at least one of the plurality of segmented areas.

Abstract: A method for recording data comprising: forming recording data by adding a pattern of connection bits selected from among a plurality of patterns of connection bits to the end of an m-bit data symbol, the selected pattern of connection bits causing an increase in an accumulated value of direct-current components per unit time when the n-bit data symbol is a special data symbol and is added to a data symbol other than the special data symbol, when m-bit data is converted into the n-bit data symbol (m<n) and when the pattern of connection bits is selected from among the plurality of patterns of connection bits to decrease the accumulated value of direct-current components per unit time to be added to the end of the m-bit data symbol; and recording the recording data formed and data indicating a recorded location of the special data symbol on a recording medium.

Abstract: An information recording medium includes a data area for recording data; and a drive information area for recording at least one piece of drive information. The data area is divided into a plurality of segmented areas in a radial direction of the information recording medium. Each at least one piece of drive information includes a recording and reproduction condition corresponding to at least one of the plurality of segmented areas.

Abstract: In an optical disk recording method, a plurality of strategies are stored, which are selectable according to a model of an optical disk, a recording rate and a linear velocity for adjusting a pulse width of a laser drive signal and a power of a laser beam to shape pits. A first strategy and a second strategy are provided for the same model of the optical disk, the same recording rate and the same linear velocity, the first strategy being designed to shorten the pulse width of the laser drive signal and increase the power of the laser beam, thereby decreasing jitters of the recorded information, the second strategy being designed to lengthen the pulse width of the laser drive signal and decrease the power of the laser beam, thereby decreasing crosstalk of the recorded information. The first strategy and the second strategy are alternatively used dependently on conditions of the recording of information.

Abstract: An input signal is quantized into a quantization-resultant signal. The quantization-resultant signal is compressed into a compression-resultant signal. The compression-resultant signal is formatted into a formatting-resultant signal corresponding to a predetermined format for a digital recording disc. The formatting-resultant signal includes segments corresponding to user data areas prescribed in the predetermined format. The compression-resultant signal is placed in the segments of the formatting-resultant signal. The formatting-resultant signal is encoded into an encoding-resultant signal of a CD format. The encoding-resultant signal is recorded on a recording medium.

Abstract: An equalizer for a high density optical disc reproducing apparatus and an equalizing method therefore are provided. The equalizer includes: a non-linear transformer, which transforms an input signal according to predetermined threshold levels; a cosine transform filter, which inverts phases of high frequency spectrum components of an output signal of the non-linear transformer; a high boost filter, which increases amplitudes of high frequency spectrum components of the input signal; and an adder, which adds an output signal of the cosine transform filter with an output signal of the high boost filter. Therefore, the equalizer can increase recording density of the optical disc in the high density optical disc reproducing apparatus and accordingly increase recording amount of information, by reducing inter-signal interference (ISI) and increasing a signal-to-noise ratio in the output signal of the equalizer. Also, the equalizer has a simple configuration.

Abstract: For encoding a current data word to be encoded, a most suitable redundant signal for the current data word to be encoded is generated by referring to a next data word to be encoded, that is, using a look-ahead decision method. The current data word to be encoded is encoded by using this redundant signal. A low-frequency component of the encoded data is effectively suppressed without decreasing encoding efficiency, by using both a regular substitution code and a stochastic substitution code, and a look-ahead determination algorithm for changing the length of words of a data segment, based on stochastic occurrence of a substitution word.

Abstract: An optical scanning device (1) includes: a radiation source (4) for supplying a radiation beam (8); a lens system (5) for transforming the radiation beam to a scanning spot (14); and a detection system (6) that includes a quadrant detector (20), an astigmatism generating element (18) for generating a first amount of coma (W31a) so as to transform the radiation beam to a first astigmatic radiation beam (21), and a coma correcting element (19) for generating a second amount of coma (W31b) so as to compensate the first amount of coma. The coma correcting element includes a correction surface (19A) having a shape defined by a function “H(r, &thgr;)” that includes the term “A.r3.cos(&thgr;)” wherein: “H” is the position of the correction surface along the optical axis of the lens system, “r” and “&thgr;” designate polar coordinates, and “A” designates a first constant dependent on the second amount of coma.

Abstract: It is an object of the present invention to record to and reproduce different types of optical disks using light beams with different wavelengths. In an optical head device for recording to and reproducing high-density optical disks using an objective lens with a large NA, a sawtooth-shaped hologram is used for recording to and reproducing conventional optical disks such as DVDs. For blue light, a sawtooth height is the light path length 2&lgr;, and second-order diffraction light is used. Red light generates first-order diffraction. The hologram is blazed and has convex lens function, and corrects chromatic aberration of the refractive lens.

Abstract: An aberration correcting unit is provided for correcting an aberration of a light beam radiated onto an object to be detected and then reflected from the object. This unit comprises an aberration correcting device comprising a first corrector configured to correct the aberration of the light beam radiated onto the object; and a second corrector configured to correct the aberration of the light beam reflected from the object and to divide the reflected light beam into a plurality of light beams. The aberration correcting unit further comprises a first driver configured to drive the first corrector and a second driver configured to drive the second corrector.

Abstract: An optical pickup apparatus in which an arrangement and adjustment of optical elements is easy. The optical pickup apparatus includes a light source to emit laser light; a beam splitter to change the travel path of incident light; an objective lens to condense light passed through the beam splitter to form a light spot on an optical recording medium; and a photodetector to receive light reflected from the optical recording medium and then passed through the beam splitter to detect an information signal and an error signal. The optical pickup apparatus further includes a grating for diffraction-transmitting incident light; a wavelength plate to change polarization characteristic of incident light; and an optical output compensating lens to compensate output of light incident from the light source. The grating, the wavelength plate, and the optical output compensating lens are disposed on an optical path between the light source and the beam splitter.

Abstract: An optical pickup with a simple configuration can be provided, by which an amount of astigmatism generated by a temperature change can be suppressed, recording and reproducing qualities can be maintained stably and its light efficiency can be enhanced. The optical pickup includes a mirror that is secured to a supporter so as to generate astigmatism due to deformation caused by a temperature change. This deformation caused by the temperature change is generated due to a difference in linear expansion coefficient between the mirror that generates the astigmatism and the supporter. This astigmatism is equal in size and is opposite in polarity to astigmatism that occurs when the parallel light passes through the beam shaping element.

Abstract: Disclosed are a light emitting module, an optical detecting module, an optical pickup apparatus formed by coupling the ultra-minimized light emitting module and the optical detecting module, and manufacturing methods thereof. To this end, ultra-minimization, a micro machining technique fit to a mass production, and a semiconductor device assembly manufacturing process are applied, thereby reducing a component cost and increasing uniformity of components.

Abstract: The invention relates to a drive system for a scanning device of an information recording or reproduction device, with a carriage coupled to a toothed rack, a gear wheel mechanism driving the toothed rack and a gear housing. It achieves the object of designing a drive system of this type alternatively and in such a way that it ensures a high speed and positioning accuracy of the carriage. For this purpose, the gear wheel mechanism is secured on a supporting element and the gear housing, the gear housing consisting of a dimensionally stable material and being pivotable with the gear wheel mechanism about a spindle which is arranged perpendicularly with respect to the toothed rack.

Abstract: A multi-layered optical disk comprising a plurality of recording layers accumulated in the thickness direction wherein a light bean is focused on one of tracks of one of the layers thereby to record and reproduce data, the optical disk being characterized in that recording layers each have an identification section storing an address of the recording layer which the identification section belongs to.

Abstract: A multi-layered optical disk comprising a plurality of recording layers accumulated in the thickness direction wherein a light beam is focused on one of tracks of one of the layers thereby to record and reproduce data, the optical disk being characterized in that recording layers each have an identification section storing an address of the recording layer which the identification section belongs to.

Abstract: An optical recording medium wherein characters can be easily recognized on an optical disk irradiated with a light through a light transmitting layer and a method of producing the same are provided. In an optical disk of a type that an optical recording layer is irradiated with a light through a light transmitting protective layer, dealing with a larger capacity, wherein one main surface of a medium substrate 15 is divided to a signal portion SG and a character portion CA, a signal portion uneven shape (15p) is formed on the signal portion SG and a character portion uneven shape (15p) is formed on the character portion CA, and depths of the signal portion uneven shape and the character portion uneven shape are 25 nm or less. Here, it is configured that characters are recorded to be able to be read as normal characters when looking from the medium substrate 15 side (Y-direction) by outlines of a region formed with the character portion uneven shape on the character portion CA.

Abstract: An optical recording medium is provided, which has reduced degradation in jitter caused by manufacturing variations of a semiconductor laser emitting laser beams or variations in output power of laser beams, and which dissipates heat in the recording layer during recording by laser beams to increase the power margin of the laser beam providing playback jitter values at a certain level or less.

Abstract: The present invention provides an optical disc for storing information, wherein the optical disc comprises a microscopic relief pattern on one side thereof, providing a structure for storing information in a digital format. The opposite side of the optical disc comprises a macroscopic relief pattern that can provide a means of protection for the optical disc.

Abstract: A data storage master disk and method of making a data storage master disk. The data storage disk master is for use in a data storage disk replication process. The data storage disk molding processes produces replica disks having a surface relief pattern with replica lands and replica grooves. The method includes providing a master substrate. The master substrate is at least partially covered with a layer of photosensitive material. A surface relief pattern having master lands and master grooves is recorded in the data storage disk master, including the steps of exposing and developing the photosensitive material. The exposing and developing of a specified thickness of photosensitive material is controlled to form master grooves extending down to a substrate interface between the master substrate and the layer of photosensitive material, such that the width of the master grooves at the substrate interface corresponds to a desired width of the replica lands.

Abstract: A data storage master disk and method of making a data storage master disk. The data storage disk master is for use in a data storage disk replication process. The data storage disk molding processes produces replica disks having a surface relief pattern with replica lands and replica grooves. The method includes providing a master substrate. The master substrate is at least partially covered with a layer of photosensitive material. A surface relief pattern having master lands and master grooves is recorded in the data storage disk master, including the steps of exposing and developing the photosensitive material. The exposing and developing of a specified thickness of photosensitive material is controlled to form master grooves extending down to a substrate interface between the master substrate and the layer of photosensitive material, such that the width of the master grooves at the substrate interface corresponds to a desired width of the replica lands.

Abstract: There are provided an optical disc that can be made highly-reliable by suppressing the occurrence of drawback such as warp and an optical disc manufacturing method that can make it possible to manufacture a highly-reliable optical disc with excellent work efficiency.

Abstract: The present invention relates to a method for modulating a signal in a system providing short-range wireless communication. In the signal, the signal is transmitted in packet format, in which each packet comprises at least a first part and a second part. In the method, the first part and the second part are modulated by using the first modulation method and the second modulation method, respectively. The second modulation method is initialized by using the first part. The invention also relates to a transceiver device and a wireless communication system, in which the method is applied.

Abstract: An apparatus and method for transmitting header information in an ultra wide band (UWB) communication system. To protect physical layer header information from errors that may occur during transmission in the UWB communication system, a transmitter transmits the header information after encoding it with an error-correcting code, whereas a receiver decodes the encoded header information with the error-correcting code. This improves the throughput in a wireless network and also decreases the bit error rate.

Abstract: A system and method for improved vertical handoff between different types of wireless network. Network allocation vector occupation and packet collision probability are used as quality of service measures, enabling vertical handoffs to be delayed until actually beneficial to quality of service. Improved wireless network cell boundary detection in vertical handoff scenarios is achieved with a Fourier-based technique in conjunction with an adaptively determined minimum operating signal strength threshold. Improved wireless network cell boundary detection enables vertical handoffs from high quality of service networks to be delayed as long as possible. Together, practical wireless network quality of service measures and improved detection of wireless network cell boundaries in vertical handoff scenarios reduce the rate of unnecessary vertical handoff resulting in higher overall quality of service experienced by a mobile computing device roaming between wireless network types.

Abstract: A method and system for managing attacks in a computer system is disclosed. The computer system is used in sending, receiving, or sending and receiving a plurality of packets, which include a plurality of administrative packets. The method and system include determining whether a congestion of the administrative packets exists. Congestion of the administrative packets indicates that a potential attack exists. The method and system also include discarding a portion of the plurality of administrative packets if it is declared that the congestion of the administrative packets exists. The portion of the plurality of packets is sufficient to ensure that a remaining portion of the plurality of packets transmitted is not more than a maximum administrative packet bandwidth limit and, if the plurality of administrative packets present a sufficient offered load, not less than a minimum administrative packet bandwidth guarantee.

Abstract: The invention relates to a bandwidth broker (34, 36) for a domain (30, 32) of a telecommunication system comprising a plurality of domains, said bandwidth broker being associated with at least one border router (40, 50) of the corresponding domain in such a way that it can obtain information about the routing tables of this border router in order to be able to allocate resources to data routes inside the domain and outside the domain.

Abstract: Methods and apparatus for aggregating IP packets over an access link between a wireless access router and a core node and for managing resource allocation to access link packet aggregates, e.g., as a function of the status of wireless communications links used to couple mobile nodes to the access router are described. Improved aggregate resource control messages and use of such messages are described. Some of the new messages allow aggregate resources for both upstream and downstream aggregates to be controlled in a single message. A single message may include information corresponding to multiple aggregates and/or multiple constituent flows included in an aggregate with aggregate direction information being included. Use of tunnels to communicate management messages, e.g., messages used to control resource allocation to aggregates is also described. Propagation of access link aggregate information is communicated to tunnel end nodes which generate packets that are communicated over the access link.

Abstract: A method is used for allocating data packet flows among a plurality of data channels of a network node. First of all, the data packets to be transmitted via the data channels are classified into a plurality of data packet flows, wherein a first data packet flow queues in a first data channel to be transmitted, and a second data packet flow is assigned to the first data channel behind the first data packet flow. The second data packet flow is then transferred from the first data channel to another data channel to be transmitted when the amounts of the first data packet flow, the second data packet flow and a third data packet flow queuing in the another data channel comply with a predetermined relationship. Meanwhile, a broadcast data packet is transmitted after the first data packet flow via the first data channel. In response to the broadcast data packet, the second data packet is transmitted via another data channel.

Abstract: A flow control method includes a step of receiving individual data of each session from a network in an individual trunk apparatus and transmitting the received individual data as a transmission side common channel data to a common buffer, a step of temporarily storing data of plural sessions received from the individual trunk apparatus all at once and monitoring the congestion of the common channel according to the common buffer use amount, and upon detection of a congestion level, a step of stopping or limiting transmission of individual data of a session corresponding to a QoS class having a low priority from the individual trunk apparatus to the common buffer.

Abstract: An alarm transfer method for use in a wide area Ethernet network has the steps of generating a plurality of fixed-length frames from an Ethernet frame sent from a client terminal, generating capsules each comprised of each of the fixed-length frames, a type field for notifying a fault, a forward relay line fault notification field for notifying a fault in a forward direction, and a backward relay line fault notification field for notifying the fault in a backward direction, multiplexing the capsules to generate a frame which is transferred to an Ethernet network, and demultiplexing capsules from a received frame to recognize a fault for each Ethernet path.

Abstract: An object of the present invention is to provide an automatic detecting apparatus for protocol nonconformity in which protocol nonconformity can be detected without necessity of technical knowledge and complex operation.

Abstract: A method and associated apparatus may implement spontaneous topology discovery in a computer network. The network may include a plurality of entities. When a change in the topology is detected, a spanning tree is created and topology information is propagated from individual entities through the spanning tree towards an entity that functions as a “root.” Arbitrarily large topologies may be discovered this way without requiring arbitrarily large amounts of memory in participating switches.

Abstract: A transmission circuit that conducts signals between integrated circuit devices includes a first driver circuit that generates a first transmit signal in response to first and second input signals, the first transmit signal being transmitted from the integrated circuit device. A first conductive line is electrically coupled to the first driver circuit and conducts the first transmit signal. A second driver circuit generates a second transmit signal in response to the first transmit signal and a third input signal, the second transmit signal being transmitted from the integrated circuit device. A second conductive line is electrically coupled to the second driver circuit and conducts the second transmit data signal. Related methods are also disclosed.

Abstract: A method for determining uplink power requirements for a transceiver in a wireless communication system includes obtaining measurements from a beacon signal occupying a first timeslot in a frame; obtaining measurements from at least one additional channel having a known transmitted signal strength and occupying a second timeslot in the frame; and utilizing the measurements to determine a path loss estimate.

Abstract: A control device includes a virtual IF set to associate with address information of an interface on a forwarding device and, when detecting that an application section accesses the virtual IF, requests the forwarding device to set a packet transfer rule for transferring a packet received on an interface to the control device while making the packet associate with the virtual IF. The forwarding device sets the packet transfer rule requested by the control device.

Abstract: To perform rapid and sure connection processing in a wireless communication system that performs communication in compliance with a wireless communication method having a congestion control function. A starting station transmits a discovery request frame and determines whether or not data is received from other communication devices in response to transmitted data. As a result of receiving data and checking FCS (Field Check Sequence), if it is detected that a received frame has been destroyed, or if no data is received from the other communication devices, a transmission distance control part decides a new transmission distance and sends a command to control transmission power to a power control part of a transmitting part, and the power control part transmits the discovery request frame again on the basis of the newly decided transmission distance to repeat discovery processing. This prevents a collision of responses from plural communication devices and ensures discoveries of other communication devices.

Abstract: Without performing a channel reservation, an arbitrary radio communication with other surrounding radio communication devices may be carried out by setting up a receiving slot according to the amount of receiving data. Each radio communication device may only manage the number of its own receiving slots so as to secure the channel required for communication by its own determination, without needing a process which is accurately synchronous with other radio communication devices. The radio communication device on the data transmission side monitors, by receiving the beacon, the increase in the number of the receiving slots of the radio communication device on the reception side, so as to transmit the data immediately when the number of the receiving slots increases. The reception acknowledgement (ACK) information from the reception side radio communication device is written in the beacon and returned.

Abstract: A CDMA network dynamically generates hard handoff (HHO) target sets to support mobile station HHO. Dynamically identifying CDMA channels or cells as targets for HHO eliminates the need for statically configured HHO target sets. In an exemplary embodiment, a source BSS identifies a first set of channels corresponding to common neighbor cells of the cells associated with the active set pilots and/or reported PBU pilots. This first set may be adjusted by removing any common neighbor cells that include soft handoff target channels, and by adding selected vertical neighbor channels of the active set pilots and/or reported PBU pilots. Channels in the first set may be grouped by carrier frequency and evaluated based on CDMA channel type, BSS affiliation and characteristics, and the target's relationship to the active set to identify a preferred HHO target set. Such operations permit dynamic determination of whether to perform inter- or intra-BSS HHO.

Abstract: An apparatus for enabling signals directed to a first telecommunications terminal to be forwarded intelligently to a second telecommunications terminal in the vicinity of the first terminal is disclosed. In particular, the illustrative embodiment automatically forwards signals from a first terminal in a network to the closest terminal in the network that the first terminal is authorized to forward to. In one illustrative embodiment, each switch in the network has an associated location server for determining the closest authorized terminal. In another illustrative embodiment, each switch employs additional logic and data for determining the closest authorized terminal.

Abstract: An auto-tuner is adapted to be used in a distributed process control network having a communications network that communicatively couples a process controller, which executes a process control routine, and one or more process devices used in a process control loop. The auto-tuner includes a first tuning element configured to cause a control entity to force the process loop to undergo an auto-tuning procedure and a tuning data stack operating within one of the process devices to receive and store a tuning signal associated with the control entity along with a time stamp indicating the time the tuning signal was acted on by the device. A measurement data stack is disposed in the same or a different process device and operates to receive and store a response or measurement signal generated by the process device along with a time stamp indicating when the response signal was generated or detected.

Abstract: An improved decoding, processing and delivery system for a centralized wireless architecture is provided for advanced determination and display of geographic information relating to a call origination party. The improved system comprises a receiving device to receive the calling number delivery (CND) message from a mobile station switching center; a central data server for storage and retrieval of specific data from a library for selectively determining the corresponding geographic information of the call origination party; a transmission device for sending data from the server; a receiving device in a wireless handset; and a readout device for displaying the geographic information of the incoming call. Accordingly, the improved system provides the user with convenient and efficient display of geographic information related to caller identification that is capable of determining an ever-increasing number of area code and local telephone exchange number.

Abstract: The performance and ease of management of wireless communications environments is improved by a mechanism that enables access points (APs) to perform automatic channel selection. A wireless network can therefore include multiple APs, each of which will automatically choose a channel such that channel usage is optimized. Furthermore, APs can perform automatic power adjustment so that multiple APs can operate on the same channel while minimizing interference with each other. Wireless stations are load balanced across APs so that user bandwidth is optimized. A movement detection scheme provides seamless roaming of stations between APs.

Abstract: A method of requesting access from a mobile station (MS) 10 to a network 8 by which to conduct user-to-user communications (e.g., requesting a dedicated traffic channel) is presented. A first time is when a user input at the mobile station 10 initiates a call. The first time as compared to a threshold time. A time-dependent code, such as a CDMA long code, is calculated for a random time if the first time is earlier than the threshold time, or for the beginning of a slot is the first time is later than the threshold time. A mobile station 10 to practice the method includes a user interface 26 whereby a call may be initiated at the first time, a processor 22 for calculating the time-dependent code, and a comparator for comparing a start threshold time to the first time. The threshold time is related to the slot time.

Abstract: A method and apparatus for long code generation in synchronous, multi-chip rate systems, wherein a first code sequence having a first bit rate, and a second code sequence having the first bit rate, the second code sequence being a time delay of the first code sequence, are multiplexed together, producing a desired long code.

Abstract: A base station controller selects codes corresponding to rate information included in a new starting call message from a mobile station, and further selects codes assignable to the mobile station out of the selected codes as candidate codes. Then, the base station controller detects codes which meet both the characteristics of being at upper level of the candidate codes in the tree structure and being assignable to other mobile station, and further detects levels of the detected codes. Detected levels for all the candidate codes are compared to find a candidate code whose level is the lowest and to assign the candidate code to the mobile station sending the new starting call message.

Abstract: A base station controller selects codes corresponding to rate information included in a new starting call message from a mobile station, and further selects codes assignable to the mobile station out of the selected codes as candidate codes. Then, the base station controller detects codes which meet both the characteristics of being at upper level of the candidate codes in the tree structure and being assignable to other mobile station, and further detects levels of the detected codes. Detected levels for all the candidate codes are compared to find a candidate code whose level is the lowest and to assign the candidate code to the mobile station sending the new starting call message.