Inventors:
Shinya Yokodate - Kamakura, JP
Koji Kaneko - Kamakura, JP
Kazuyuki Saigusa - Kamakura, JP
Tatsuhiko Mizushima - Kamakura, JP
Scott A. Lewis - Davis CA
Gary S. Fletcher - Rocklin CA
Assignee:
Mitsubishi Denki Kabushiki Kaisha - Tokyo
Mitsubishi Electronics America, Inc. - Cypress CA
International Classification:
H04M 1100
H04N 712
Abstract:
A static video telephone for sending an image captured by an image capture-system and receiving a video signal transmitted over a telephone line. A video signal formed for transmission has a frame format including a phase shift correction data signal in addition to a frame synchronization signal, an amplitude calibration signal, an ID (information data) signal, and image data signal. The video telephone includes a frequency shift correction data generating circuit which is activated when frequency shifts are detected in the received signal and produces frequency-shift correction data. The frequency-shift correction data is then delivered to a subsequent demodulation timing generating circuit which scales phase errors in the received signal to produce phase error correction data. Both frequency-shift correction data and phase error correction data are combined together to produce a demodulation timing signal. With this signal, the received signal is demodulated.
