Abstract: An optical CDMA encoder-decoder is constructed by combining arrayed-waveguide gratings, matrix optical switches, and delay lines, otherwise by combining arrayed-waveguide grating and variable delay lines, thus providing an encoding process that a wavelength change with respect to time in optical pulses. The light includes a wide spectrum band width inserted into a CDMA encoder/decoder and is demultiplexed by arrayed-waveguide gratings. Each wave length according to the demultiplexed spectrum component spreads out in the time region based on delay time differences produced by delay lines having differential optical lengths. Thus, in CDMA, the dependency of wavelengths on delay time can be set arbitrarily.

Abstract: An optical transmitter includes a light source emitting input light; and a modulator modulating the input light in accordance with an input electric signal to generate an optical transmission signal. The transmitter also includes a monitor which detects frequency fluctuation of the optical transmission signal. The modulator is controlled so as to optimize the amount of frequency fluctuation of the optical transmission signal.

Abstract: A synchronization acquiring method capable of reducing the length of time required to perform in wireless communication a synchronization acquiring operation is provided when the mobile station transits from a sleep state to an active state. A synchronization acquiring apparatus capable of performing such a synchronization acquiring method is also provided. The method has the following three steps. In the first step, multiple correlation values are obtained between the input data supplied from a base station to the mobile station and multiple phases of a spreading code multiplied to the input data in the mobile station before the mobile station transits from the active state to the sleep state, multiple phases of the spreading code that correspond to the correlation values are determined, and the multiple phases are stored. In the second step, phases of the spreading code multiplied to the input data are determined using the phase when the mobile station transits from the sleep state to the active state.

Abstract: K×K optical switch unit according to the present invention is comprised of input ports 1-1, . . . 1-36, 1×M optical matrix switches 5-1-1, . . . 5-4-9 connected with the input ports 1-1, . . . 1-36, N×N optical matrix switches 7-1-1, . . . 7-4-2, and 10-1-1, . . . 10-4-2 connected with the 1×M optical matrix switches 5-1-1, . . . 5-4-9, an M×1 optical matrix switches 13-1-1, . . . 13-4-9 connected with the N×N optical matrix switches 7-1-1, . . . 7-4-2, and 10-1-1, . . . 10-4-2, and output ports 2-1, . . . 2-36 connected with the M×1 optical matrix switches 13-1-1, . . . 13-4-9, where K=M×N, M and N are integers more than 1.

Abstract: A digitized image is encoded by detecting edges in the image, encoding the position and sharpness of the detected edges, filtering the image by a low-pass filter to generate a low-frequency image, and encoding the low-frequency image. A digitized image encoded in this way is reconstructed by generating a horizontal edge image and a vertical edge image from the encoded edge position and sharpness information, synthesizing a pair of high-frequency images by filtering the horizontal and vertical edge images with an edge synthesis filter, decoding the low-frequency image, and performing an inverse wavelet transform on the decoded low-frequency image and the high-frequency images.

Abstract: A perovskite crystallized ferroelectric substance is formed over a lower electrode. A precursor solution, which serves as a ferroelectric film, is applied thereto and dried, followed by low-temperature anneal under the condition of a perovskite crystallization temperature or lower. Further, an upper electrode is formed and thereafter subjected to high-temperature anneal at a temperature of the perovskite crystallization temperature or higher to thereby perfectly crystallize the ferroelectric film, whereby a semiconductor element interposed between the electrodes can be formed.

Abstract: Since the ferroelectric memory device is a 1T1C type, the size of one memory cell can be smaller than that of a 2T2C type. In this ferroelectric memory device, the reference potential does not have to be generated when data is read.

Abstract: A process for separating ore particles from gangue particles comprises the steps of (1) conditioning the particles with an agent comprising a compound having both a surface-selective functional group and a detectable moiety, to selectively coat either the ore particles or the gangue particles, to the substantial exclusion of the other; (2) detecting the coated particles; and (3) separating the detected, coated particles from the substantially uncoated particles. In one embodiment, the detectable moiety is fluorescent and detecting is performed under ultraviolet radiation.