Network for retrieval and video transmission of information

• US 5,831,679 A
• Filed: 10/28/1996
• Issued: 11/03/1998
• Est. Priority Date: 06/14/1991
• Status: Expired due to Fees

• Current Assignee: WAVO Corporation
• Original Assignee: WavePhore, Inc.
• Inventors: Norrish, Jay B, Montgomery, Gerald D
• Primary Examiner(s): Faile, Andrew I.
• Assistant Examiner(s): Miller, John W.
• Application Number:
  US08/739,497
• Time in Patent Office: 736 Days
• Field of Search: 348/6-13, 348/487, 348/473, 348/461, 348/469, 348/465, 348/463, 348/468, 348/475, 348/486, 348/536, 348/464, 348/467
• US Class Current: 348/473
• CPC Class Codes: H04N 7/0803 using frequency interleaving, e.g. with precision offset
• CPC Class Codes: H04N 7/081 the additional information signals being transmitted by means of a subcarrier
• CPC Class Codes: H04N 7/10 Adaptations for transmission by electrical cable H04N7/12 takes precedence

Abstract

Signal processors for permitting the transparent, simultaneous transmission and reception of a volume of information in the video bandwidth is disclosed. The volume of data is selected in response to receiving a signal at a transmitter site. The signal processor in the transmitter rasterizes the volume of information at the horizontal scanning rate and modulates the volume of information with a data carrier at a non-integral multiple of the horizontal scanning rate to provide a frequency interleaved combined signal. The combined signal is transmitted during the active video portion of each video line.

Claims

1. A method of transmitting data over a video network, the network having a plurality of channels, at least some of the channels having a rasterized video signal format, each video signal format having a bandwidth and active video intervals, the active video intervals separated by horizontal blanking intervals, the method comprising:

sending a signal having low information content over a low bandwidth channel from a first site;

receiving the signal at a second site;

selecting a volume of information to be transmitted to the first site responsive to the received signal;

furnishing the selected information at a high data rate;

combining the selected information at a high data rate within the bandwidth of a video signal during active intervals for transmission over the video network to provide a combined signal;

transmitting the combined signal through at least one of the channels; and

receiving the transmitted combined signal at the first site;

wherein the bandwidth includes luminance and chrominance spectra, the chrominance spectra having a chrominance subcarrier, the method further including combining the volume of information within the video signal bandwidth at a frequency greater than the chrominance subcarrier to produce a combined signal.

2. A transmitter for transmitting data over a video network, the network having a plurality of channels, each channel having a rasterized video signal format, each video signal format having a bandwidth and active video intervals and a color carrier, the active video intervals separated by horizontal blanking intervals, the transmitter comprising:

means for sending a signal having low information content over a low bandwidth medium from a first site;

a first receiving device for receiving the signal at a second site;

means for selecting a volume of information to be transmitted to the first site responsive to the received signal;

means for furnishing the selected information at a data rate of greater than about 100 Kilobits per second;

means for combining the selected information within the bandwidth of a video signal above the color carrier during the active intervals for transmission over the video network to provide a combined signal;

a transmission device for transmitting the combined signal through at least one of the channels; and

a second receiving device for receiving the transmitted combined signal at the first site.

3. The transmitter of claim 2, wherein the bandwidth includes luminance and chrominance components, the combining means further including:

means for generating a carrier at an odd quarter, non-integral multiple of the frequency of the raster rate of the video signal of the at least one channel;

means for modulating the carrier based upon the volume of information so that an amount of spectral energy of the modulated carrier is frequency interleaved with the chrominance and luminance components of the video signal of the at least one channel to provide a modulated signal; and

means for injecting the modulated signal into the video signal bandwidth of the at least one channel during the active intervals.

4. The transmitter of claim 2, wherein the bandwidth includes luminance and chrominance spectra, the chrominance spectra having a vestigial chrominance sideband, and wherein the combining means combines the volume of information with the video signal in the bandwidth so that the volume of information lies substantially within the vestigial chrominance sideband.

5. The transmitter of claim 2, wherein the transmission device generates a carrier having a first phase and the receiving device tunes to the carrier at a second phase;

the transmission device further comprising;

means for inserting into the volume of data a phase synchronization marker; and

means for synchronizing the first phase of the carrier generated by the transmission device to the second phase of the carrier at the receiving device.

6. The transmitter of claim 2, wherein the volume of information comprises graphical image data.