Abstract: An optical receiver including an optical divider to divide a signal light from an optical transmission line into two portions, a first and a second dispersion compensators, each dispersion compensator having variable dispersion compensation to compensate chromatic dispersions of each of the two portions of signal light output from the optical divider, and a data demodulator to demodulate a data carried by a signal light output from the first dispersion compensator. The optical receiver further includes an optical autocorrelator to operate on a signal light output from the second dispersion compensator and a controller to control the second dispersion compensator to increase autocorrelation of the optical autocorrelator, and to control the first dispersion compensator according to the result of said controlling the second dispersion compensator.

Abstract: A communication zone is defined by a plurality of cells, which are separated from one another and has respective fixed base stations. The base stations in the first cell and the last cell are capable of bidirectional communication with a mobile station, while other base stations are capable of unidirectional communication. The base stations are connected to a zone control station, which controls communications with the mobile station within the zone.

Abstract: Each of a transmitter (1) and a receiver (2) divides temporarily-shared data into one or more purification blocks and one or more disposable blocks, and mixes each purification block so as to enlarge a Hamming distance between corresponding purification blocks being held by the transmitter (1) and the receiver (2) by using a Hamming distance amplification effect. The transmitter (1) Vernam-encrypts the mixed data with the disposable data and transmits the mixed data to the receiver (2), and the receiver (2) decrypts the received Vernam-encrypted data by using a disposable block owned thereby, and compares the Hamming distance between the purification block owned thereby with the mixed data with a predetermined value so as to judge whether each purification block can be shared between the transmitter (1) and the receiver (2).

Abstract: A communication satellite facility and a satellite communication system adapted to respond flexibly to development and change of communication technologies occurring on the ground even after satellites have been launched. The system includes a first satellite having an antenna function, a second satellite having a modem function and a third satellite having a server function all of which are launched into one and same slot of geosynchronous orbit and connected one to another by wideband intersatellite communication. A ground station connected to a ground network communicates with the first satellite.

Abstract: Upon recovery of communication, this recovery is detected by communication recover detector and then optimal times duplicated pseudo acknowledgements calculated by arithmetic unit are transmitted from ACK transmitter. During normal state, advertisement is made in small value of advertised receive window size and immediately after recovery state, advertisement is made in expanded window size.

Abstract: A method and apparatus are provided that make it possible to speedily measure, and obtain images of, the three-dimensional distribution of electric fields in integrated circuits, using electro-optic sampling. The sampling is performed using a plurality of electric field sensors, each comprising an electro-optic crystal layer, a light-reflecting layer that is in close contact with the electro-optic crystal layer, and a separation layer that is in close contact with the reflection layer, separating the reflection layer from the object to be measured.

Abstract: The present invention is directed to improve convenience to the user. A path extending from the present location S of a mobile terminal to a destination D via a base station is calculated (S2), distances between base stations on the calculated path and the present location are calculated, and the closest base station is determined as a contents delivery base station (S7). Grace time for the mobile terminal to pass through the contents delivery base station is calculated. Then, scheduled time to deliver the contents to the mobile terminal is calculated (S8). While monitoring a travel state of the mobile terminal (S10 to S12), the contents are delivered to the mobile terminal near the contents delivery base station (S14).

Abstract: To create a network that connects a plurality of wireless communication systems to create optimal systems for various environments, and that seamlessly integrates the resulting systems together in order to provide more efficient and advanced service in general. A network system that can seamlessly integrate wireless communication systems employs a heterogeneous network architecture with at least four building blocks, including a mobile host 40, a wireless access network 41, a common core network 42, and an external network 43.

Abstract: A method of easily manufacturing a nano-gap electrode by using a focused ion beam lithography includes a layer depositing step of depositing an electrode layer and a metal mask layer in this order on an insulating substrate, a mask pattern forming step of etching the metal mask layer by using the focused ion beam and thereby forming a mask pattern, a dry etching step of transferring a pattern to the electrode layer by dry etching, and a wet etching step of removing the metal mask layer by using a solution that selectively dissolves the metal mask layer compared to the electrode layer.

Abstract: Only a first radio station is equipped with a local oscillation signal source. A signal transmitted to a second radio station includes local oscilaation signal components used to up-convert a modulated intermediate frequency band signal in addition to intermediate frequency band signal components. The second radio station that receives the signal from the first radio station extracts and regenerate the local oscillation signal used at the first radio station using a local oscillation signal regenerator. The extracted and regenerated local oscillation signal is used to down-convert modulated radio signal components to the intermediate frequency band and simultaneously up-convert to the radio frequency band the modulated intermediate frequency band signal to be transmitted to the first radio station.

Abstract: This apparatus calculates a direction of a light source (the sun) in a coordinate system having a 3D geometrical model of an object placed therein from geographic information on an object and a shooting time of image data, and detects a shadow region cast on the 3D geometrical model by a beam from a light source direction so as to identify the shadow region in the image data based on correspondence information. It uses a predetermined reflection model to estimate effects of shadings caused to the 3D geometrical model and determines a parameter of a reflection model suited to estimated shadings. And it performs calculation for removing the effects of the shadows and shadings by using the determined parameter from pixel values sampled from the image data so as to fit the calculated pixel values in the 3D geometrical model and generate a texture model.

Abstract: The present invention's method and apparatus to generate test sequences for communication protocols input the data of the finite state machines (FSM) representing the specification of the communication protocols, and convert the test sequence generation problem to the SAT problem, and generate test sequences for communication protocols by solving the SAT problem. In addition, the present invention converts the test sequence generation problem to the SAT problem by modifying the FSM and describing the test sequence generation problem by using a conjunctive normal form formula based on the modified FSM. According to the present invention, by considering the multiple UIO sequences and the overlapping of the UIO sequences, the minimum length test sequence to check whether the states described in the specification of the protocol exist in the implementation of the FSM can be generated.

Abstract: The present invention enable to separate source signals from mixture signals into which the source signals are mixed temporally and spatially, where the number of source signals is more than or equal to the number of mixture signals. A signal storing portion 12 stores the mixture signals input into a signal input portion 11, and a formulation portion 131 in a signal separation portion 13 extracts the mixture signals stored in the signal storing portion 12 and formulates them as an operation expression using a basis matrix composed of plural small matrixes that consist of bases with time symmetry. A learning algorithm application portion 132 applies a learning algorithm based on overcomplete representations, a mixture matrix calculating portion 133 calculates a mixture matrix, a source signal estimating portion 134 estimates source signals separated from the mixture signals, and an output portion 14 outputs the calculated mixture matrix and the estimated source signals.

Abstract: An optical control electromagnetic wave circuit comprises a unit composed of a semiconductor layer, a transparent substrate, and a transparent grounded conductive layer and a displaying unit. The semiconductor layer is formed on the transparent substrate, and the photoconductive layer is formed on the opposite surface of the transparent substrate. The displaying unit faces the transparent grounded layer. The shape of the radio wave circuit which is displayed on the displaying unit is mapped on the semiconductor layer to form the radio wave circuit. It can be realized to dynamically change the radio wave circuit by changing the shape of the radio wave circuit displayed on the displaying unit. The radio wave circuit can be provided freely and flexibly.

Abstract: An optical frequency converter that can use a low-amplitude, high-frequency signal for converting a wide range of optical frequencies. The optical frequency converter includes a device for modulating a lightwave of a preset frequency with a modulation signal to generate a group of sidebands thereof, a device for selecting sidebands from among the group of sidebands, and a device for changing modulation signal frequencies and selecting specific sidebands.

Abstract: A laser oscillator comprises a laser medium, an optical excitation laser diode that irradiates the laser medium with light, a polarizer disposed on an optical path of the laser medium at a first end thereof, a first Porro prism disposed with the optical path coinciding with a point on a ridgeline thereof and with the ridgeline parallel or perpendicular to a plane of incidence of the polarizer, and a second Porro prism disposed on the optical path of the laser medium at a second end thereof with the optical path coinciding with a point on a ridgeline thereof. An angle formed by the two ridgelines of the first and second Porro prisms is a predetermined angle other than 0 degrees, 90 degrees, 60 degrees, 45 degrees and 36 degrees, 30 degrees.

Abstract: A real-time contents editing system edits a large number of images and/or voices which are present in a dispersed fashion on the Internet, and distributes the edited images and/or voices to a plurality of users. The system includes a plurality of video cameras, a plurality of distribution modules each adapted to code an input image taken by a corresponding video camera by use of a coding standard which enables coding while selecting one of a plurality of coding algorithms and to distribute the coded input images, a plurality of receiving modules each adapted to receive and display the images, and at least one editing module. Each distribution module changes, in accordance with the performance level of a machine to be used, the kind and use frequency of a video object plane (VOP) to be used, to thereby select a coding algorithm which enables highly efficient compression.

Abstract: To easily detect the position corresponding to the explanation of a detection area in input data, the apparatus sets an extraction unit, an extraction expression for a highlight, and the position of an extraction area. From the extraction area, an equivalent of the extraction unit is extracted, and an extracted unit corresponding to the extraction expression is stored in storage means. Then, input data is checked from the left. If an equivalent of the current extraction unit is stored in the storage means, it is highlighted.

Abstract: An optical modulation apparatus includes an optical signal input section, an optical signal propagation path, an optical modulator that modulates the phase of optical signals in at least two of a plurality of optical paths, and a wavelength selective filter that selectively reflects and transmits. Optical signals input via the input section are divided into a plurality of optical paths at a branching point and phase modulated by the phase modulator, that divides the optical path into a plurality of optical paths. Light transmitted by the filter is output via the output section, while light reflected by the filter travels back along the optical path and is again phase modulated by the phase modulator combined at the branching point and output from the input section as an intensity modulated optical signal.

Abstract: A method of easily manufacturing a nano-gap electrode by using a focused ion beam lithography includes a layer depositing step of depositing an electrode layer and a metal mask layer in this order on an insulating substrate, a mask pattern forming step of etching the metal mask layer by using the focused ion beam and thereby forming a mask pattern, a dry etching step of transferring a pattern to the electrode layer by dry etching, and a wet etching step of removing the metal mask layer by using a solution that selectively dissolves the metal mask layer compared to the electrode layer.