Multipath mitigation circuit for home network

• US 10,284,162 B2
• Filed: 03/27/2018
• Issued: 05/07/2019
• Est. Priority Date: 02/01/2010
• Status: Active Grant

• Current Assignee: PPC Broadband Incorporated (Belden Inc.)
• Original Assignee: PPC Broadband Incorporated (Belden Inc.)
• Inventors: Alkan, Erdogan, Palinkas, Raymond W.
• Primary Examiner(s): Lee, Benny T
• Assistant Examiner(s): Rahman, Hafizur
• Application Number:
  US15/937,239
• Publication Number:
  US 20180219523A1
• Time in Patent Office: 406 Days
• Field of Search: 333167, 333168, 333175, 333176, 333 81 A, 333100, 333129, 333132, 455296, 455307
• CPC Class Codes: H03H 7/01 Frequency selective two-port networks
• CPC Class Codes: H03H 7/0138 Electrical filters or coupling circuits
• CPC Class Codes: H03H 7/0161 Bandpass filters H03H7/12 takes precedence
• CPC Class Codes: H03H 7/06 including resistors H03H7/075, H03H7/09, H03H7/12, H03H7/13 take precedence
• CPC Class Codes: H03H 7/1741 Comprising typical LC combinations, irrespective of presence and location of additional resistors when resistors are present, also classify in H03H7/06 - H03H7/07
• CPC Class Codes: H03H 7/1758 Series LC in shunt or branch path H03H7/1791 takes precedence
• CPC Class Codes: H03H 7/1766 Parallel LC in series path H03H7/1783 takes precedence

Abstract

A filter circuit is provided having multipath interference mitigation. The filter includes a signal path extending from an input to an output. The signal path includes a conductive path and a ground. A pass band filter is disposed along the signal path between the input and the output. The pass band filter passes a first frequency spectrum in a provider bandwidth, and attenuates a second frequency spectrum in a home network bandwidth. The filter circuit further includes a multipath interference mitigation leg operatively branched from the signal path. The multipath interference mitigation leg increases a return loss of the home network bandwidth. A frequency response of the filter circuit is characterized by an insertion loss characteristic between the input and the output being less than 3 dB in the provider bandwidth, and more than 20 dB in the home network bandwidth.

Claims

1. A filter circuit, comprising:

a pass band filter portion disposed along a signal path between a provider-side port and a user-side port, the pass band filter portion configured to pass a first frequency spectrum in a provider bandwidth and attenuate a second frequency spectrum in a home network bandwidth; and

a multipath interference mitigation leg branched in parallel from the pass band filter portion, the multipath interference mitigation leg configured to decrease multipath distortions by improving a return loss of the home network bandwidth, wherein a frequency response of the filter circuit comprises;

a first insertion loss in the provider bandwidth that is less than 3 dB;

a second insertion loss in the home network bandwidth that is more than 20 dB; and

a return loss at the user-side port is more than 10 dB.

2. The filter circuit of claim 1, wherein the return loss of the home network bandwidth is more than 20 dB.

3. The filter circuit of claim 2, wherein the multipath interference mitigation leg further comprises a shunt resistor.

4. The filter circuit of claim 3, wherein the provider bandwidth has a impedance of 75 ohms, and the shunt resistor has a resistance value of about 75 ohms.

5. The filter circuit of claim 1, wherein the pass band filter portion comprises an inductor/capacitor arrangement having tank elements.

6. The filter circuit of claim 1 wherein the multipath interference mitigation leg comprises an attenuator portion.

7. The filter circuit of claim 6, wherein the attenuator portion comprises a Tee-type resistive attenuator.

8. The filter circuit of claim 1, wherein the return loss of the home network bandwidth is more than20 dB, and wherein a return loss of the provider bandwidth is more than 20 dB.

9. The filter circuit of claim 1, wherein the first frequency spectrum comprises a spectrum of frequencies carrying media content and the second frequency spectrum comprises an open spectrum of frequencies carrying personal data content.

10. The filter circuit of claim 1, wherein the first and second insertion loss are present between the provider-side port and the user-side port.

11. The filter circuit of claim 1, wherein the return loss of the home network bandwidth is more than 10 dB, and wherein a return loss of the provider bandwidth is more than 10 dB.

12. The filter circuit of claim 1, wherein the frequency response of the filter circuit comprises a third insertion loss in a bandwidth that is greater than the provider bandwidth and the home network bandwidth, and wherein the third insertion loss is more than 20 dB.

13. The filter circuit of claim 1, wherein:

the provider bandwidth is from about 5megahertz (MHz) to about 1002 MHz; and

the home network bandwidth is from about 1125 MHz to about 1525 MHz.

14. A filter circuit, comprising:

a pass band filter portion disposed along a signal path between a provider-side port and a user-side port, the pass band filter portion configured to pass a provider bandwidth signal received at the provider-side port and attenuate a home network bandwidth signal received at the user-side port, wherein the provider bandwidth comprises a cable television (CATV) bandwidth, and wherein the home network bandwidth comprises a multimedia over coax alliance (MoCA) bandwidth; and

a multipath interference mitigation leg operatively branched in parallel from the signal path, the multipath interference mitigation leg configured to decrease interference related to transmissions of downstream and upstream signals along the signal path, wherein a frequency response of the filter circuit comprises a first insertion loss in the provider bandwidth is less than 3 dB, and a second insertion loss in the home network bandwidth is more than 20 dB.

15. The filter circuit of claim 14, wherein the multipath interference mitigation leg comprises an absorptive portion.

16. The filter circuit of claim 15, wherein the multipath interference mitigation leg comprises a termination resistor configured to match an impedance of a line load of the signal path.

17. The filter circuit of claim 15, wherein the absorptive portion comprises at least one lumped element comprising two capacitors in series, with an inductor/capacitor series connection shunted to ground from a node between the two capacitors.

18. The filter circuit of claim 14, wherein a frequency response of the filter circuit results in attenuation between the provider-side port and the user-side port, the attenuation being higher in the home network bandwidth than in the provider bandwidth, and the frequency response further results in a decrease in energy reflection at the user-side port.

19. A filter circuit, comprising:

a pass band filter portion disposed along a signal path between a provider-side port and a user-side port, the pass band filter portion configured to pass a provider bandwidth and attenuate a home network bandwidth, wherein frequencies within the provider bandwidth are less than a predetermined frequency, and wherein frequencies within the home network bandwidth are greater than the predetermined frequency, and wherein the predetermined frequency is between about 1002 megahertz (MHz) and about 1125 MHz; and

a multipath interference mitigation leg operatively branched from the signal path, the multipath interference mitigation leg configured to decrease reflections due to an impedance mismatch, wherein a frequency response of the filter circuit results in an attenuation between the provider-side port and the user-side port, the attenuation being less in the provider bandwidth than in the home network bandwidth, the frequency response comprises a first insertion loss in the provider bandwidth that is less than 3 dB and a second insertion loss in the home network bandwidth that is more than 20 dB, and the frequency response further results in a decrease in reflection of energy at the user-side port.

20. The filter circuit of claim 19, wherein the filter circuit is a point-of-entry filter in a cable television network.

21. The filter circuit of claim 19, wherein the multipath interference mitigation leg comprises at least two lumped elements, each lumped element comprising two capacitors in series and an inductor/capacitor series connection, the inductor/capacitor series connection being shunted to ground from a node between the two capacitors.