Matsushita Electric Industrial Co., Ltd.

Kunio Ninomiya

Seiji Sakashita

Hisaya Kato

Kazuya Ueda

Takaaki Konishi

Hideki Kirino

Koichi Komoda

Hiroyuki Satoh

Takami Uemura

Junya Nishizaka

According to a copy protection method of the present invention, as for a component video signal which is composed of a luminance signal and two color-difference signals, copy inhibition information is superimposed upon a first color-difference signal and information indicating that the copy inhibition information is included in the first color-difference signal is superimposed upon a second color-difference signal. Or copy inhibition information is superimposed upon the luminance signal, a vertical blanking interval, or a horizontal blanking interval. Accordingly, it can be judged whether or not the video is capable of copying, without making the viewers conscious, whereby component video signals can be easily copy protected.

Copy guard method and digital broadcast receiving apparatus

A slim television broadcast receiver employing antennas in which a waveguide is formed by a metallic plate and a copper foil on a printed circuit board. An insulating magnetic element is loaded so as to block one of a pair of aperture planes of the waveguide, and the aperture area is enlarged by beveling the other aperture plane. Tuning elements are provided on opposed sides with respect to the center part of the other aperture, which antennas are placed on opposed side ends of the slim television broadcast receiver, thereby performing electronic tuning and phase synthesis diversity reception.

Broadcast receiving antenna and television broadcast receiver

To present a digital broadcast demodulator, in a demodulator of digital terrestrial wave broadcast for transmitting coded digital video and audio information in a packet form, capable of detecting packet synchronism stably and precisely, controlling the AGC, and processing the clock regeneration, in spite of inferior environments for receiving broadcast, such as deterioration of C/N of signal due to weak electric field, or strong ghost or multipath characteristic of terrestrial waves.

Demodulator for demodulating digital broadcast signals

A carrier wave NTSC component or a VSB pilot signal in an IF signal is extracted and judged. Then, on the basis of the judgment result, either of demodulation circuitandwhich is appropriate for the received broadcast wave is switched. Information of co-broadcasting programs for analog and digital broadcasts are acquired from EPG and memorized. In case of high-speed channel search, analog broadcast is preferentially switched to. In case of co-broadcasting, the analog broadcast program is displayed on the screen at the beginning, and then, the digital broadcast program is switched when the data decoding is completed. Therefore, it is possible to provide a receiver for receiving digital and analog broadcasts, which can perform switching automatically to a demodulation circuit appropriate for the channel selected modulated wave, and which can also seamlessly switch the channels between analog and digital broadcasts, thereby screen display can be switched smoothly at switching from analog broadcast to digital broadcast.

Multi-system correspondence receiver

A signal of a desired channel is selected by a tuner from digital broadcasting is received by an antenna. The condition of the radio wave received by the antenna, which is judged from an AGC signal of the signal of the channel selected by the tuner, a Sync signal detected by a synchronization establishment unit and the number of errors which have not been corrected by a forward error corrector , is displayed on an indicator. The receiving direction or position of the antenna can be easily decided on the basis of the condition of the received radio wave of the antenna, which is displayed on the indicator, so that received video has a C/N within thresholds.

Digital broadcasting demodulation apparatus with a direction adjustment indicator for the receiving antenna

A broadcast receiving apparatus provides multifunctionality to cope with analog modulated input signals as well as digital input signals modulated by various types of modulation schemes. The apparatus comprises a detector for detecting the modulation scheme of input signals, and a switch for switching one or more of the characteristic of a filtering section, an amplifying section, and a detection section, depending upon the detected modulated scheme.

Broadcast receiving apparatus

A Vestigal Sideband (VSB) demodulator having a clock generator for generating a clock signal based on a symbol frequency of the VSB signal; an A/D converter for converting the VSB signal into a digital signal based on the clock signal of the clock generator; a first multiplier for multiplying the digital signal by a first value sequence and generating a first multiplier output signal; a second multiplier for multiplying the digital signal by a second value sequence and generating a second multiplier output signal; a complex type filter for shaping and VSB demodulation of the multiplier output signals and generating Inphase and Quadrature data output signals; a decimating circuit for decimating the Inphase and Quadrature data output signals and generating decimated signals; a complex multiplier for multiplying the decimated signals by a predetermined value and generating multiplied output signals; an error detector for detecting a frequency deviation and a phase deviation from the multiplied output signals and generating the predetermined value for the complex multiplier; and DC offset canceler for removing a DC component from a portion of the multiplied output signals of the complex multiplier.

VSB demodulator

A demodulation apparatus of digital detection processing type of the invention offers versatility as consumer equipment in mobile communications, ATV, satellite broadcasting, CATV, and the like. A modulated wave output is obtained by multiplying an input digitally modulated wave signal by a local oscillating signal from a local oscillator. The obtained modulated wave output has a center frequency which is substantially equal to the symbol frequency. The modulated wave output is A/D converted at a rate which is four times as high as the symbol frequency, so as to be output as interleaved I and Q digital data. The I and Q data is split, and the split I and Q data are multiplied by coefficients of '+1' and '-1', respectively. The multiplied two output signals are selectively output. Thus, the data multiplied by the coefficients of '+1' and '-1' are alternately output for the I and Q signals, so as to perform the digital detection. The processed I and Q data are subjected to digital channel filter processing for spectrum shaping/An interpolation signal for one of the output signals of digital channel filters is generated and output. An amplitude level value of the interpolation signal is controlled, and then the timing of the interpolation signal is matched with the timing of the other one of the output signals of the digital channel filters. The phase error detection and the waveform shaping are performed for the I and Q data having the matched timings, and the data identification is performed.

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Niihama, Japan

Kunio Ninomiya