Systems and methods for providing redundant back-up to a video transmission system

• US 20030163829A1
• Filed: 05/14/2002
• Published: 08/28/2003
• Est. Priority Date: 02/22/2002
• Status: Active Grant

• Current Assignee: Qwest Communications International Incorporated (Lumen Technologies, Inc.)
• Original Assignee: Qwest Communications International Incorporated (Lumen Technologies, Inc.)
• Inventors: Ackerman, Kurt E., Coufal, William C., Adams, Randall E.
• Granted Patent: US 8,505,063 B2
• Time in Patent Office: Days
• US Class Current: 725/118
• CPC Class Codes: H04N 1/32683 Preventive counter-measures, e.g. using redundant hardware, or anticipating a fault arrangements for keeping a communication line open H04N1/32795
• CPC Class Codes: H04N 21/42607 for processing the incoming bitstream
• CPC Class Codes: H04N 21/44209 Monitoring of downstream path of the transmission network originating from a server, e.g. bandwidth variations of a wireless network arrangements for maintenance or administration in data switching networks involving bandwidth and capacity management H04L41/0896
• CPC Class Codes: H04N 21/4586 Content update operation triggered locally, e.g. by comparing the version of software modules in a DVB carousel to the version stored locally deployment, distribution, installation, update of software G06F8/65; error detection or correction of the data by redundancy during software upgrading G06F11/1433; arrangements for updating broadcast information or broadcast-related information H04H60/25
• CPC Class Codes: H04N 21/6106 specially adapted to the downstream path of the transmission network
• CPC Class Codes: H04N 5/38 Transmitter circuitry for the transmission of television signals according to analogue transmission standards H04N5/14 takes precedence
• CPC Class Codes: H04N 7/16 Analogue secrecy systems; Analogue subscription systems

Abstract

A system and method for providing video signals wherein the video signals from a single video source may be separately passed over two different transmission paths. Each transmission path includes an encoder, a communications channel and a decoder. The output of each communications path at the decoder provides the video signals and an alarm signal. The alarm signal indicates an error or disruption of the video signals over the corresponding communications path. The outputted video and alarm signals are provided to a video protection switch (VPS) device which provides the video signal from the second transmission path if the alarm signals indicates an error or disruption in the first transmission path. In one embodiment, the VPS has multiple switches, one for each of plural video sources, and a redundant switch and protection ports. The redundant switch and protection ports may be connected to receive the video and alarm signals if one of the switches in the VPS fails.

Claims

1. A video transmission system with redundant back-up facilities, comprising:

a video source;

a first video transmission path for receiving a video signal from the video source and providing a first video output signal and an error signal, the error signal having a first state when no error is detected in the first video output signal and a second state upon detection of an error in the first video output signal;

a second video transmission path for receiving a video signal from the video source and providing a second video output signal; and

a video protection switch for receiving the first and second video output signals from the first and second video transmission paths and providing the first video output signal when the error signal is in the first state and a providing the second video output signal when the error signal is in the second state.

2. A video transmission system for carrying video signals from first location to a second remote location, comprising:

a video source at the first location;

a first video transmission path in electrical communication with the video source, the first video transmission path comprising a first encoder, a first communication channel and a first decoder, the first decoder providing a first video output signal and an alarm relay signal, the alarm relay signal reflecting a disruption in the first video output signal;

a second video transmission path in electrical communication with the video source, the second video transmission path comprising a second encoder, a second communication channel and a second decoder, the second decoder providing a second video output signal; and

a video protection switch at the second remote location, comprising;

a first input for receiving the first video output signal from the first decoder, and a second input for receiving the second video output signal from the second decoder;

an output;

a switch connected for receiving both the first and second video output signals, and pre-set to provide the first video output signal to the output of the video protection switch; and

an alarm input for receiving the alarm relay signal;

wherein when the first decoder detects a disruption in the video signal in the first transmission path, the alarm relay signal provided to the alarm input causes the video protection switch to provide the second video signal at the output of the video protection switch.

3. The system as recited in claim 2, wherein the second decoder provides a second alarm relay signal reflecting a disruption in the second video output signal, and the video protection switch further comprises a second alarm input for receiving the second alarm relay signal, and wherein when the second decoder detects a disruption in the video signal in the second transmission path, the second alarm relay signal provided to the second alarm input causes the video protection switch to provide the first video signal at the output of the video protection switch.

4. The system as recited in claim 2, wherein the video protection switch further comprises:

first and second protection inputs;

a protection switch;

a protection alarm input; and

a protection signal output;

wherein when the switch of the video protection switch fails, the video output signals from the first decoder and second decoder may be provided to the first and second protection inputs, respectively, and the alarm signal provided to protection alarm input, so that the protection switch can be used to replace the failed switch.

5. The system as recited in claim 2, wherein the video protection switch further comprises:

an alarm control controlling the switch and connected to the alarm input.

6. The system as recited in claim 5, wherein the alarm input further receives a second alarm relay signal from the second decoder, and wherein after providing the second video output signal in response to the first alarm signal, the alarm control controls the switch based on second alarm relay signal from the second decoder.

7. The system as recited in claim 5, wherein after switching in response to the received alarm relay signal from the first decoder, the video protection switch continues to provide the second video output signal at the output of the video protection switch until manually reset.

8. The system as recited in claim 2, wherein the disruption of the video signal is a failure in the first encoder, first channel, or first decoder.

9. A method for providing redundant back-up functions to a video transmission system, comprising:

providing a first encoder and a second encoder connected to a video source;

providing a plurality of channels, a first channel connected to the first encoder and a second channel connected to the second encoder;

providing a first decoder and a second decoder, with the first decoder providing an alarm relay signal, the first decoder in electrical communication with the first encoder by way of the first channel and providing a first video signal from the video source, and the second decoder in electrical communication with the second encoder by way of the second channel and providing a second video signal from the video source;

providing a video protection switch, the video protection switch comprising a first and a second signal input connected for receiving the first and second video signals from the first and second decoders,

an alarm input connected for receiving the alarm relay signal from the first decoder,

a signal output, and

a switch controlled by the alarm relay signal;

wherein when the first decoder detects a signal disruption, the first decoder sends the alarm relay signal to the alarm input and, in response, the switch changes state, from one state providing the first video signal at its output to a second state providing the second video signal at its output.

10. A method for transmitting a video signal from a video source, comprising:

encoding a plurality of signals from a video source;

transmitting each encoded signal on a different one of a plurality of channels;

at a remote location from the video source, decoding each signal separately;

inputting each of the decoded signals into a video protection switch;

outputting a first of the decoded signals from the video protection switch; and

if there is an error in the first decoded signal, switching the state of the video protection switch to output a second of the decoded signals from the video protection switch.

11. The method as recited in claim 10, wherein the error in the first decoded signal is a failure in the transmission by way of the channel or an error during encoding or decoding.

12. A video transmission system with redundant back-up facilities, comprising:

video source means for providing video signals;

first video transmission path means for receiving a video signal from the video source means and providing a first video output signal and an error signal, the error signal having a first state when no error is detected in the first video output signal and a second state upon detection of an error in the first video output signal;

second video transmission path means for receiving a video signal from the video source and providing a second video output signal; and

video protection switch means for receiving the first and second video output signals from the first and second video transmission path means and providing the first video output signal when the error signal is in the first state and a providing the second video output signal when the error signal is in the second state.

13. The system of claim 12, wherein the video protection switch means is at a location remote from the video source means.

14. The system of claim 13, wherein the first and second transmission path means each comprise a fiber optic cable.

15. The system of claim 12, wherein the video source means comprises a plurality of video sources, each video source providing a video signal, and wherein the first and second transmission path means both carry the same video signal from each video source.

16. The system of claim 12, wherein each of the first and second transmission means comprises an encoder for encoding the video signals from the video source means, a fiber optic cable for carrying the encoded signals, and a decoder for decoding the encoded signals and providing the decoded signal to the video protection switch means, and wherein the decoder in the first transmission means provides the error signal when an error is detected in the decoded signal.