Split linked A/B switch apparatus

• US 6,449,768 B1
• Filed: 04/28/1999
• Issued: 09/10/2002
• Est. Priority Date: 04/28/1999
• Status: Expired due to Term

• Current Assignee: ATX Networks Incorporated (United Communications Group, Inc.)
• Original Assignee: ADC Telecommunications Incorporated (TE Connectivity Limited)
• Inventors: Carlson, Craig, Keller, John C., Manderfield, Sara, Oftedahl, Rick, Brown, Jeffrey O.
• Primary Examiner(s): Miller, John
• Assistant Examiner(s): BELIVEAU, SCOTT E
• Application Number:
  US09/301,163
• Time in Patent Office: 1,231 Days
• Field of Search: 725/148, 725/149, 725/144, 725/146, 725/107, 725/119, 725/127, 725/114, 725/116, 725/117, 725/138, 725/147, 348/705
• US Class Current: 725/119
• CPC Class Codes: H04B 10/032 using working and protection systems H04J14/0287 takes precedence
• CPC Class Codes: H04N 7/104 Switchers or splitters
• CPC Class Codes: H04N 7/22 Adaptations for optical transmission

Abstract

A switch apparatus is used in the transmission of a redundant Cable TV (CTV) signal. The redundant CTV signal can be a symmetric split linked redundant CTV signal or an asymmetric split linked redundant CTV signal. The switch apparatus is capable of handling both the symmetric and asymmetric redundant CTV signal where primary channels are split into multiple parts. The asymmetrical splitting of the primary channels is where one part contains more channels than another part. The switch apparatus includes a plurality of switches and a monitor device to detect a failure in the split signal path before the split signals are combined to be transmitted to downstream end-users. Upon detecting a failure, the switches are switched from primary channels to secondary channels by a controller. After the signal is returned, the switches are switched back to the primary channels. A delay timer may be included in the switch apparatus to avoid incidental or temporary signal recovery.

Claims

1. A switch apparatus, comprising:

a first input port including a first switch for switching between a first position to input a first set of primary. channels and a second position to connect to a termination;

a second input port including a second switch for switching between a first position to input a second set of primary channels and a second position to input a set of secondary channels, the set of secondary channels including the sum of the first and second sets of primary channels;

a controller for controlling the first switch and the second switch, wherein when the controller detects a predetermined condition, the controller switches the first and second switches simultaneously from the first positions to the second positions, and when the controller detects that the predetermined condition is over, the controller switches the first and second switches simultaneously from the second positions to the first positions; and

an output port including a combiner for outputting combined first and second sets of primary channels when the first and second switches are switched to the first positions, and for outputting the set of secondary channels when the first and second switches are switched to the second positions.

2. A switch apparatus of claim 1, wherein the controller includes a monitor for monitoring a condition of the first set of primary channels proximate at the first input port;

when the condition of the first set of primary channels reaches the predetermined condition, the controller switches the first and second switches from the first positions to the second positions.

3. A switch apparatus of claim 2, wherein the controller includes a timer;

when the predetermined condition is over, the controller switches the first and second switches from the second positions to the first positions after a period defined by the timer.

4. A switch apparatus of claim 1, wherein the controller includes a monitor for monitoring a condition of the second set of primary channels proximate at the second input port;

when the condition of the second set of primary channels reaches the predetermined condition, the controller switches the first and second switches from the first positions to the second positions.

5. A switch apparatus of claim 4, wherein the controller includes a timer;

when the predetermined condition is over, the controller switches the first and second switches from the second positions to the first positions after a period defined by the timer.

6. A switch apparatus of claim 1, wherein the controller includes:

a first monitor for monitoring a condition of the first set of primary channels proximate at the first input port;

a second monitor for monitoring a condition of the second set of primary channels proximate at the second input port; and

when the condition either of the first and second sets of primary channels reaches the predetermined condition, the controller switches the first and second switches from the first positions to the second positions.

7. A switch apparatus of claim 6, wherein the controller includes a timer;

when the predetermined condition is over, the controller switches the first and second switches from the second positions to the first positions after a period defined by the timer.

8. A switch apparatus of claim 1, wherein the first set of channels includes more channels than the second set of channels.

9. A switch apparatus of claim 1, wherein the first set of channels includes less channels than the second set of channels.

10. A switch apparatus of claim 1, wherein the first set of channels includes the same number of channels as the second set of channels.

11. A cable system for transmitting primary channels which are split into at least two sets and secondary channels from a head-end of a receiver to an end user, the cable system comprising:

the head-end for receiving signals

cables for transmitting the primary channels and the secondary channels to a hub;

the hub comprising a switch apparatus including;

a first input port including a first switch for switching between a first position to input the first set of primary channels and a second position to connect to a termination;

a second input port including a second switch for switching between a first position to input the second set of primary channels and a second position to input the secondary channels;

a controller for controlling the first switch and the second switch, wherein when the controller detects a predetermined condition, the controller switches the first and second switches simultaneously from the first positions to the second positions, and when the controller detects that the predetermined condition is over, the controller switches the first and second switches simultaneously from the second positions to the first positions; and

an output port including a combiner for outputting combined first and second sets of primary channels when the first and second switches are switched to the first positions, and for outputting the set of secondary channels when the first and second switches are switched to the second positions.

12. A cable system of claim 11, wherein the controller includes a monitor for monitoring a condition of the first set of primary channels proximate at the first input port;

when the condition of the first set of primary channels reaches the predetermined condition, the controller switches the first and second switches from the first positions to the second positions.

13. A cable system of claim 12, wherein the controller includes a timer;

when the predetermined condition is over, the controller switches the first and second switches from the second positions to the first positions after a period defined by the timer.

14. A cable system of claim 11, wherein the controller includes a monitor for monitoring a condition of the second set of primary channels proximate at the second input port;

when the condition of the second set of primary channels reaches the predetermined condition, the controller switches the first and second switches from the first positions to the second positions.

15. A cable system of claim 14, wherein the controller includes a timer;

when the predetermined condition is over, the controller switches the first and second switches from the second positions to the first positions after a period defined by the timer.

16. A cable system of claim 11, wherein the controller includes a first monitor for monitoring a condition of the first set of primary channels proximate at the first input port;

a second monitor for monitoring a condition of the second set of primary channels proximate at the second input port;

when the condition either of the first and second sets of primary channels reaches the predetermined condition, the controller switches the first and second switches from the first positions to the second positions.

17. A cable system of claim 16, wherein the controller includes a timer;

when the predetermined condition is over, the controller switches the first and second switches from the second positions to the first positions after a period defined by the timer.

18. A cable system of claim 11, wherein the first set of channels includes more channels than the second set of channels.

19. A cable system of claim 11, wherein the first set of channels includes less channels than the second set of channels.

20. A cable system of claim 11, wherein the first set of channels includes the same number of channels as the second set of channels.

21. A method of switching between primary channels and secondary channels, the primary channels being split into at least two sets, comprising:

connecting a first switch to a first position and a second switch to a first position;

monitoring the first set of primary channels and the second set of primary channels;

a) if either of the first and second sets of the primary channels is in a predetermined condition;

1) switching the first switch to a second position and the second switch to a second position simultaneously; and

2) outputting the secondary channels;

b) if neither of the first and second sets of the primary channels is in the predetermined condition;

1) combining the first and second sets of the primary channels; and

2) outputting the combined primary channels.

22. A method of claim 21, further comprising switching from the second positions of the first and second switches to the first positions when the predetermined condition is over.

23. A method of claim 22, further comprising delaying a period of time before switching from the second positions to the first positions when the predetermined condition is over.

24. A method of claim 21, wherein the splitting of the primary channels is asymmetric such that the first set of the primary channels has more channels than the second set of the primary channels.

25. A method of claim 21, wherein the splitting of the primary channels is asymmetric such that the first set of the primary channels has less channels than the second set of the primary channels.

26. A method of claim 21, wherein the splitting of the primary channels is symmetric such that the first set of the primary channels includes the same number of channels as the second set of the primary channels.