Telephonic communications – Having light wave or ultrasonic link for speech or paging... – Including fiber optic link within telephone network
Patent
1990-02-21
1992-11-17
Dwyer, James L.
Telephonic communications
Having light wave or ultrasonic link for speech or paging...
Including fiber optic link within telephone network
358 85, H04M 1100, H04M 714
Patent
active
051649802
ABSTRACT:
Apparatus and method are provided for the simultaneous transmission of video information and audio information in substantially real time over an ordinary voice grade telephone line having limited bandwidth in the range of about 300-3400 Hz. Because of the limited bandwidth of the ordinary telephone line, the video and audio information are compressed before transmission thereof. Each of the video information and audio information is separately compressed, mixed together and then further compressed. After the further compression, a composite signal, which includes the mixture of video and audio information, is asynchronously transmitted over the same bandwidth of the ordinary telephone line. Upon reception, the compressed information is expanded and separate video information and audio information are reproduced for viewing and hearing by the receiving party. To reduce the size of the apparatus, application specific integrated circuits (ASICs) are employed. A state machine controller apparatus is integrated with the ASIC technology to control the transfer and storing of video information and audio information and also to control the operation of the various compression and expansion stages associated with the transmitting and receiving channels.
REFERENCES:
patent: 3873771 (1975-03-01), Kleinerman et al.
patent: 4099202 (1978-07-01), Cavanaugh
patent: 4237484 (1980-12-01), Brown et al.
patent: 4485400 (1984-11-01), Lemelson et al.
patent: 4544950 (1985-10-01), Tu
patent: 4593318 (1986-06-01), Eng et al.
patent: 4715059 (1987-12-01), Cooper-Hart et al.
patent: 4774574 (1988-09-01), Daly et al.
patent: 4849811 (1989-07-01), Kleinerman
patent: 4955048 (1990-09-01), Iwamura et al.
patent: 4962521 (1990-10-01), Kamatsu et al.
patent: 4985911 (1991-01-01), Emmons et al.
patent: 4991009 (1991-02-01), Suzuki et al.
J. Anderson, et al. of Widcom, Inc., Campbell, Calif., Electronics, "Codec squeezes color teleconferencing through digital telephone lines," Jan. 26, 1984, pp. 113-115.
Bush Daniel R.
Patel Ashok
Alkanox Corporation
Dwyer James L.
Woo Stella L.
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