Nippon Hoso' Kyokai

Sanyo Electric Co., Ltd.

Kyb Corporation

Minoru Honda

Yutaka Tanaka

Makoto Suzuki

Taiji Nishizawa

Taiichiro Kurita

Kazuhiko Shibuya

Yoshinori Izumi

Seiichi Gohshi

Junji Kumada

Kazumasa Enami

Isao Kondo

Makoto Okui

Haruo Okuda

Ryoichi Yajima

Shoichi Suzuki

Yoshio Takeuchi

Kaoru Watanabe

Yoshikazu Tomida

Syugo Yamashita

Masaru Kanazawa

Toshiyuki Takegahara

Yukihiro Nishida

Yasuaki Kanatsugu

Hideki Suganami

Yuichi Iwadate

Yoshiharu Hoshino

Hisakazu Kato

Makoto Tadenuma

Jun'ichi Ishida

Ichiro Yuyama

Terumasa Tokumoto

Toshihiro Kubo

Sumio Yano

Hiroyuki Hamazumi

Toshihiko Susaki

An error rate measuring apparatus includes a demodulator, and data from the demodulator is applied to a decoding circuit in which an error bit number is evaluated for each of a BIC portion and a packet portion. In the BIC portion, if a synchronization is settled, the error bit number is evaluated by comparing received BICs and a predetermined BIC pattern, and if the synchronization is not settled, the error bit number is determined as eight (8) bits. In the packet portion, if a frame synchronization is settled and decoding is successful, the error bit number is calculated by comparing data before decoding and data after decoding with each other. If the frame synchronization is settled but the decoding is unsuccessful, a presumed error bit number is set according to the number of packets being decoded successfully in a first time horizontal direction, and if the frame synchronization is not settled, a predetermined error bit number is set. In each of the BIC portion and the packet portion, a bit error rate is calculated on the basis of the error bit number for each measurement range, and displayed on a monitor.

Error rate measuring apparatus

In order to reduce radio interference jamming in the same channel exerting from an adjacent broadcasting area when a digitized image signal of, for example, high-definition television utilizing an idle channel in ground broadcasting of television is transmitted, a digital string such as a binary coded image signal is thinned out every predetermined digital period so as to be divided into two groups. Continuous digital strings of two series are formed by converting clock rates of the respective groups and converted into multi-value digits. Intermediate carriers are then modulated with the digital signals of the two series having their requisite bands compressed through quadrature modulation to form modulated carriers, and the modulated carriers are transmitted in bands of two divisional channels which escape from adjacent video and voice carriers, the power of which is responsible for the radio interference in the same channel. The carriers are subsequently received for reconstruction.

Digital modem for reducing interference in the same channel of another

High resolution vertical and horizontal components of a high definition video signal are combined with a standard broadcast system video signal, such as the NTSC system, in which high frequency horizontal resolution components are sampled and used to modulate at least a first sub-carrier signal. The first sub-carrier is frequency interleaved onto the standard broadcast signal. Vertical high resolution components are time compressed and time division multiplexed onto top and bottom portions of the standard broadcast signal. The modified broadcast signal can be decoded by a standard receiver to display a standard resolution video image, while receivers designed to decode the modified signal can time division demultiplex the vertical high resolution components and demodulate the horizontal high resolution components, combine these components with the standard components, and generate a high definition video image.

Receiver and channel compatible encoding/decoding system for high

A method and system for multiplexing additional audio information in the form of pulse code modulation (PCM) audio signals onto a television signal. The PCM audio signal is time multiplexed into scanning retrace intervals of the video signal. At a receiver, the bit error rate of the decoded PCM audio signal is compared with a threshold so as to switch the audio output from the PCM audio signal to a conventional FM demodulated audio signal when the bit error rate exceeds the predetermined threshold. In this way, the benefits of both PCM audio and FM audio can be obtained by utilizing the higher immunity of FM signals in low signal-to-noise ratio environments, while the high fidelity PCM audio signal is utilized when the signal-to-noise ratio environment is relatively high.

Method and system for transmitting and receiving PCM audio signals in

A multiple sub-sampling encoding/decoding system performing interfield and interframe offset sub-sampling of a broad bandwidth television signal. The system compresses the television signal to fit, for example, to the transmission bandwidth of the standard television systems, compensates the transmission characteristics, and achieves the optimal frequency allocation of the modulated transmission signal.

Multiple sub-sampling transmitting/receiving system performing

Growing community of inventors

Tokyo, Japan

Minoru Honda