CATV Entry Adapter and Method for Preventing Interference with eMTA Equipment from MoCA Signals

• US 20100125877A1
• Filed: 01/21/2010
• Published: 05/20/2010
• Est. Priority Date: 10/21/2008
• Status: Active Grant

• Current Assignee: PPC Broadband Incorporated (Belden Inc.)
• Original Assignee: PPC Broadband Incorporated (Belden Inc.)
• Inventors: Wells, Chad T., Egan, John M. JR.
• Granted Patent: US 8,510,782 B2
• Time in Patent Office: Days
• US Class Current: 725/78
• CPC Class Codes: H04L 12/2801 Broadband local area networks
• CPC Class Codes: H04M 11/066 Telephone sets adapted for data transmision
• CPC Class Codes: H04N 21/6118 involving cable transmission, e.g. using a cable modem
• CPC Class Codes: H04N 21/6168 involving cable transmission, e.g. using a cable modem
• CPC Class Codes: H04N 7/17309 Transmission or handling of upstream communications

Abstract

A community access or cable television (CATV) entry adapter interfaces to a CATV network and serves as a hub in a Multimedia over Coax Alliance (MoCA) network. MoCA signals communicated between active ports of the entry adapter are rejected by MoCA frequency rejection filters to avoid interfering with the functionality of an eMTA subscriber device connected to a passive port of the entry adapter, without interfering with the passage of CATV upstream and downstream active and passive signals.

Claims

1. A CATV entry adapter used at subscriber premises and having an entry port for communicating downstream and upstream signals with a CATV network, a passive port for communicating downstream and upstream signals with eMTA subscriber equipment connected to the passive port, and a plurality of active ports for communicating CATV upstream and downstream signals with CATV active subscriber equipment connected to the active ports, the active ports also communicating MoCA signals between MoCA-enabled subscriber equipment connected to the active ports in a MoCA network, the CATV entry adapter comprising:

a first bidirectional splitter/combiner having a common terminal connected to the entry port to communicate the CATV downstream and upstream signals with the CATV network, the first splitter/combiner also having first and second separate signal component legs, the first splitter/combiner splitting CATV downstream signals into split CATV downstream signals and supplying the split CATV downstream signals to the first and second signal component legs, the first splitter/combiner creating a single combined upstream signal from each upstream signal received at the first and second signal component legs and supplying the combined upstream signal to the common terminal;

a passive signal communication path extending between the first signal component leg of the first splitter/combiner and the passive port to conduct passive signals between the passive port and the first signal component leg of the first splitter/combiner;

an active signal communication path extending from the second signal component leg of the first splitter/combiner to conduct active signals to and from the second signal component leg of the first splitter/combiner;

a second bidirectional splitter/combiner having a common terminal and a plurality of separate signal component legs which each connect to an active port, the second splitter/combiner splitting each signal received at its common terminal into split signals and supplying each split signal to each of the signal component legs, the second splitter/combiner also creating a combined active signal from each CATV upstream signal and MoCA signal received at each signal component leg and supplying the combined active signal to its common terminal;

the second splitter/combiner performing the aforesaid signal splitting and signal combining on CATV downstream signals, CATV upstream signals and MoCA signals; and

a first MoCA frequency rejection filter connected between the active signal communication path and the second splitter/combiner, the first MoCA frequency rejection filter rejecting a significant majority of the power from MoCA signals present at the common terminal of the second splitter/combiner and passing the CATV upstream and downstream signals communicated to and from the active ports.

2. A CATV entry adapter as defined in claim 1, wherein:

the first MoCA frequency rejection filter reflects power from MoCA signals received from the common terminal of the second splitter/combiner back into the common terminal of the second splitter/combiner; and

the second splitter/combiner supplies the MoCA signals reflected from the first MoCA frequency rejection filter as split reflected MoCA signals to the signal component legs of the second splitter/combiner.

3. A CATV entry adapter as defined in claim 2, wherein:

the MoCA signals traverse between the signal component legs of the second splitter/combiner when communicating the MoCA signals between the MoCA-enabled subscriber equipment connected to the active ports;

the second splitter/combiner supplies the MoCA signals reflected from the first MoCA frequency rejection filter as split reflected MoCA signals to the signal component legs of the second splitter/combiner; and

the power of the split reflected MoCA signals adds to the power of the MoCA signals which traverse between the signal component legs of the second splitter/combiner to enhance the power of the MoCA signals communicated in the MoCA network.

4. A CATV entry adapter as defined in claim 3, wherein:

the traversal of the MoCA signals between signal component legs of the second splitter/combiner attenuates the strength of MoCA signals available at each signal component leg of the second splitter/combiner resulting from the traversal; and

attenuation of the MoCA signals reflected from the first MoCA frequency rejection filter and conducted through the second splitter/combiner is less than the attenuation of the split reflected MoCA signals caused by traversing between each signal component leg of the second splitter/combiner.

5. A CATV entry adapter as defined in claim 1, further comprising:

a second MoCA frequency rejection filter connected between the first signal component leg of the first splitter/combiner and the passive port in the passive signal communication path, the second MoCA frequency rejection filter preventing a significant majority of the power from MoCA signals at the first signal component leg of the first splitter/combiner from reaching the passive port, and the second MoCA frequency rejection filter passing the CATV upstream and downstream signals communicated to and from the passive port without substantial attenuation.

6. A CATV entry adapter as defined in claim 5, wherein:

each of the first and second MoCA frequency rejection filters have substantially the same capacity for rejecting MoCA signals.

7. A CATV entry adapter as defined in claim 5, wherein:

each of the first and second MoCA frequency rejection filters have at least a 30 dB capacity for rejecting MoCA signals.

8. A CATV entry adapter as defined in claim 5, further comprising:

a third MoCA frequency rejection filter connected between the common terminal of the first splitter/combiner and the entry port, the third MoCA frequency rejection filter preventing a significant majority of the power from MoCA signals present at the common terminal of the first splitter/combiner from entering the CATV network, and preventing a substantial majority of the power from any MoCA signals signals present on the CATV network from passing through the entry adapter to the passive and active ports, and passing the CATV upstream and downstream signals communicated to and from the entry port without substantial attenuation.

9. A CATV entry adapter as defined in claim 8, wherein:

each of the first, second and third MoCA frequency rejection filters have substantially the same capacity for rejecting MoCA signals.

10. A CATV entry adapter as defined in claim 9, wherein:

each of the first and second MoCA frequency rejection filters have at least a 30 dB capacity for rejecting MoCA signals.

11. A CATV entry adapter as defined in claim 8, further comprising:

a housing; and

wherein;

the entry port, the passive port and all of the active ports are connected to the housing;

each of the ports is formed in part by a cable connector; and

the first and second bidirectional splitter/couplers, the passive and active signal communication paths, and the first and second and third MoCA frequency rejection filters are located within the housing.

12. A CATV entry adapter as defined in claim 1, further comprising:

one other MoCA frequency rejection filter connected between the common terminal of the first splitter/combiner and the entry port, the other MoCA frequency rejection filter preventing a significant majority of the power from MoCA signals present at the common terminal of the first splitter/combiner from entering the CATV network, and preventing a substantial majority of the power from any MoCA signals present on the CATV network from passing through the entry adapter to the passive and active ports, and passing the CATV upstream and downstream signals communicated to and from the entry port without substantial attenuation

13. A CATV entry adapter as defined in claim 1, wherein:

the active signal communication path includes a CATV active downstream signal communication path and a CATV active upstream signal communication path;

the CATV active downstream signal communication path includes at least one active electronic component requiring a supply of electrical power for conditioning CATV downstream signals communicated from the entry port through the CATV active downstream signal communication path to the active ports;

the CATV active downstream signal communication path passing CATV downstream signals in a predetermined CATV downstream frequency band and rejecting substantially all downstream signals of other frequencies;

the CATV active upstream signal communication path communicating CATV upstream signals from the subscriber equipment connected at the active ports to the CATV network;

the CATV active upstream signal communication path passing CATV upstream signals in a predetermined CATV upstream frequency band and rejecting substantially all upstream signals of other frequencies; and

the CATV passive signal communication path and the second MoCA frequency rejection filter both have no active electronic components requiring a supply of electrical power for influencing CATV passive downstream and upstream signals communicated between the entry port and the passive port.

14. A CATV entry adapter as defined in claim 13, wherein:

the one active electronic component requiring a supply of electrical power of the CATV active downstream signal communication path comprises a signal amplifier.

15. A CATV entry adapter as defined in claim 13, wherein:

the CATV active upstream signal communication path comprises an ingress noise mitigation circuit operative to suppress upstream ingress noise from the active ports.

16. A method of preventing MoCA signals communicated between MoCA-enabled subscriber devices connected in a MoCA network and to a CATV entry adapter from interfering with communications from an eMTA subscriber device connected by the CATV entry adapter to a CATV network, comprising:

connecting the eMTA subscriber device to a passive port of the entry adapter;

communicating passive downstream and upstream signals between the CATV network and the eMTA subscriber device through the entry adapter and the passive port;

connecting each MoCA-enabled subscriber device to one of a plurality of active ports of the entry adapter;

communicating MoCA signals through the entry adapter and the active ports between the MoCA-enabled subscriber devices in the MoCA network;

splitting CATV downstream signals received from the CATV network within the entry adapter into split CATV downstream signals and supplying one split downstream signal to the passive port and supplying other split CATV downstream signal to the active ports;

combining upstream signals received from the passive and active ports within the entry adapter into a combined upstream signal and supplying the combined upstream signal from the entry adapter to the CATV network;

combining CATV upstream signals and MoCA signals received from the active ports within the entry adapter into a combined active signal;

rejecting a significant majority of the power from MoCA signals within the combined active signal by supplying the combined active signal to a first MoCA frequency rejection filter within the entry adapter; and

passing the CATV upstream signals within the combined active signal through the first MoCA frequency rejection filter without substantial attenuation.

17. A method as defined in claim 16, further comprising:

reflecting split reflected MoCA signals from the first MoCA frequency rejection filter to the active ports.

18. A method as defined in claim 17, further comprising:

traversing MoCA signals between the active ports when communicating the MoCA signals between the MoCA-enabled subscriber equipment connected to the active ports; and

adding the power of the split reflected MoCA signals and the power of the traversed MoCA signals at the active ports to enhance the power of the MoCA signals conducted from the active ports to the MoCA-enabled subscriber equipment.

19. A method as defined in claim 16, further comprising:

rejecting a significant majority of the power of any MoCA signals from the combined active signal otherwise conducted to the passive port by supplying the combined active signal to a second MoCA frequency rejection filter within the entry adapter; and

passing the CATV downstream and upstream signals communicated with the passive port through the second MoCA frequency rejection filter without substantial attenuation.

20. A method as defined in claim 19, further comprising:

endowing each of the first and second MoCA frequency rejection filters with substantially the same capacity for rejecting MoCA signals.

21. A method as defined in claim 19, further comprising:

rejecting with a third MoCA frequency rejection filter within the entry adapter a significant majority of the power from MoCA signals that would otherwise be conducted from the entry adapter to the CATV network and that would otherwise be conducted from the CATV network into the entry adapter without substantially attenuating the CATV upstream and downstream signals communicated to and from the entry adapter.

22. A method as defined in claim 21, further comprising:

endowing each of the first and second MoCA frequency rejection filters each with at least a 30 dB capacity for rejecting MoCA signals.

23. A method as defined in claim 16, further comprising:

rejecting with one other MoCA frequency rejection filter within the entry adapter a significant majority of the power from MoCA signals that would otherwise be conducted from the entry adapter to the CATV network and that would otherwise be conducted from the CATV network into the entry adapter without substantially attenuating the CATV upstream and downstream signals communicated to and from the entry adapter.

24. A method as defined in claim 16, further comprising:

including at least one active electronic component requiring a supply of electrical power within the entry adapter for conditioning CATV downstream signals communicated through the entry adapter to the active ports; and

utilizing no active electronic components requiring a supply of electrical power within the entry adapter for influencing downstream and upstream signals communicated between the entry port and the passive port.

25. A method as defined in claim 24, further comprising:

using an ingress noise mitigation circuit within the entry adapter to suppress upstream ingress noise originating from the subscriber equipment connected to the active ports.