NEC

About: NEC is a company organization based out in Tokyo, Japan. It is known for research contribution in the topics: Signal & Layer (electronics). The organization has 33269 authors who have published 57670 publications receiving 835952 citations. The organization is also known as: NEC Corporation & NEC Electronics Corporation.

Semiconductor integrated circuit and semiconductor integrated circuit device

Abstract: A semiconductor integrated circuit device has a plurality of basic cells. The basic cells are placed in a matrix form, and are formed on a semiconductor substrate. Each of the basic cells includes a wire selection portion and a logic gate portion. The logic gate portion has a MOS transistor. The wire selection portion has a thin-film transistor serving as a transfer gate. The wire selection portion is placed over the logic gate portion via an interlayer insulating film.

An apparatus for a synchronized playback of audio-video signals

Abstract: An apparatus for producing synchronized playback of compressed digital data of audio-video signals from a desired portion of the digital data. The apparatus can be used in a system having comparatively low data processing ability, and work independent of the resolution of a software timer of the system. The apparatus comprises a frame counter for obtaining a reference time indicating reproduction time passage of the audio signal component from a reproduced data amount of the audio signal component. A delay detector detects progress of the video signal component in reference to the reference time.

Optical head apparatus for different types of disks

Abstract: In an optical head apparatus for two or more different types of discs (A, A', B), there are provided a first light source (11) for a first wavelength light beam, a second light source (12) for a second wavelength light beam, and an objective lens (6, 6', 6'') for leading the first and second wavelength light beams to one of the discs. A holographic optical element (5', 5'') is provided to converge or diverge only one of the first and second wavelength light beams. Or, an aperture limiting element (2801) is provided to adjust an effective numerical aperture of the objective lens for only one of the first and second wavelength light beams.

Method and apparatus for establishing and maintaining frame synchronization in a satellite communication system

Abstract: An apparatus and method for establishing frame synchronization in a satellite communication system which receives a modulated signal having frames, such that a unique word and data are multiplexed in each of the frames. A demodulator demodulates the modulated signal and provides a demodulated signal including the unique words. A signal detector compares the signal power of the demodulated signal with a threshold signal and provides a detection signal. A selector provides, in accordance with the detection signal, the detected demodulated signal or fixed data as a selected signal. A frame synchronizing circuit detects the unique word from the selected signal, when the demodulated signal is provided as the selected signal by the selector, and establishes frame synchronization in accordance with the detected unique word.

Method of transmitting terminating call signals within a restricted duration and a base station and a portable unit for use in the same

Abstract: A portable unit that may be called from a base station through a radio control channel by a succession of terminating call signals that is sent through the control channel from the base station to the portable unit for a first or restricted time duration (T1), selected in consideration of a battery saving period of a battery saving operation carried out in the portable unit. Within the battery saving period, the portable unit is put into transient active and inactive states during a first time interval and a second time interval, respectively. Selection is made so that the first time duration is longer than the second time interval to receive at least one of the terminating call signals within the first time duration in the portable unit. The base station monitors an acknowledgement signal for a second time duration (T2) after the lapse of the first time duration and interrupts the control channel when the acknowledgement signal is not received within the first and the second time durations. In the portable unit, the battery saving operation is released when the presence of the terminating call signals is detected by a squelch circuit.