Filter circuit

Patent metadata

Field	Value
Publication number	US-11444592-B2
Application number	US-202016938218-A
Country	US
Kind code	B2
Filing date	Jul 24, 2020
Priority date	Feb 1, 2010
Publication date	Sep 13, 2022
Grant date	Sep 13, 2022

Abstract

A filter circuit includes a pass band filter portion configured to pass signals in a first frequency spectrum and attenuate or block signals in a second frequency spectrum. The first frequency spectrum and the second frequency spectrum do not overlap. The pass band filter portion is configured to cause a return loss of more than 10 decibels (dB) in the first frequency spectrum.

First claim

What is claimed is:

1. A filter circuit, comprising:
an input;
an output;
a pass band filter portion between the input and the output, wherein the pass band filter portion is configured to pass signals between the input and the output in a first frequency spectrum and attenuate or block signals between the input and the output in a second frequency spectrum;
an interference mitigation portion configured to be connected to the pass band filter portion, wherein the interference mitigation portion comprises an attenuator circuit that is configured to increase a return loss at the output in the second frequency spectrum; and
wherein the second frequency spectrum is higher than the first frequency spectrum.

2. A filter circuit comprising:
an input;
an output;
a pass band filter portion between the input and the output, wherein the pass band filter portion is configured to pass signals between the input and the output in a first frequency spectrum and attenuate or block signals between the input and the output in a second frequency spectrum; and
an interference mitigation portion configured to be connected to the pass band filter portion, wherein the interference mitigation portion comprises an attenuator circuit that is configured to increase a return loss at the output in the second frequency spectrum without substantially affecting a frequency response of a remainder of the filter circuit; and
wherein the second frequency spectrum is distinct from, and higher than, the first frequency spectrum.

3. The filter circuit of claim 2 , wherein the pass band filter portion is configured to cause an insertion loss of less than 3 decibels (dB) between the input and the output in the first frequency spectrum, and wherein the insertion loss comprises an amount of attenuation the signals receive as the signals pass from the input to the output.

4. The filter circuit of claim 2 , wherein the pass band filter portion is configured to cause an insertion loss of more than 20 decibels (dB) between the input in the first frequency spectrum and the output in the second frequency spectrum, and wherein the insertion loss comprises an amount of attenuation the signals receive as the signals pass from the input to the output.

5. The filter circuit of claim 2 , wherein the pass band filter portion is configured to cause the return loss at the output to be more than 10 decibels (dB) in the first frequency spectrum, and wherein the return loss comprises a measure of a reflected energy from the signals.

6. The filter circuit of claim 1 , wherein the pass band filter portion is configured to cause the return loss at the output to be more than 10 decibels (dB) in the second frequency spectrum, and wherein the return loss comprises a measure of a reflected energy from the signals.

7. The filter circuit of claim 2 , wherein the attenuator circuit is also configured to increase the return loss at the input in the second frequency spectrum, and wherein the return loss is substantially the same at the input and the output.

8. The filter circuit of claim 7 , wherein the return loss is substantially the same at the input and the output due to symmetry of the filter circuit.

9. The filter circuit of claim 2 , wherein the interference mitigation portion comprises:
a first high pass portion configured to be connected to the pass band filter portion;
a second high pass portion; and
an attenuator portion comprising one or more resistors, wherein the attenuator portion is connected in series between the first and second high pass portions.

10. A filter circuit, comprising:
means for passing signals between an input and an output in a first frequency spectrum and attenuating or blocking signals between the input and the output in a second frequency spectrum, wherein the second frequency spectrum is distinct from, and higher than the first frequency spectrum; and
means for increasing a return loss at the output in the second frequency spectrum without substantially affecting a frequency response of a remainder of the filter circuit.

11. The filter circuit of claim 10 , wherein the means for passing signals between the input and the output in the first frequency spectrum and attenuating or blocking signals between the input and the output in the second frequency spectrum is configured to cause an insertion loss of less than 3 decibels (dB) in the first frequency spectrum.

12. The filter circuit of claim 10 , wherein the means for passing signals between the input and the output in the first frequency spectrum and attenuating or blocking signals between the input and the output in the second frequency spectrum are configured to cause an insertion loss of more than 20 decibels (dB) in the second frequency spectrum.

13. The filter circuit of claim 10 , wherein the means for passing signals between the input and the output in the first frequency spectrum and attenuating or blocking signals between the input and the output in the second frequency spectrum are configured to cause the return loss at the output to be more than 10 decibels (dB) in the first frequency spectrum.

14. The filter circuit of claim 10 , wherein the means for passing signals between the input and the output in the first frequency spectrum and attenuating or blocking signals between the input and the output in the second frequency spectrum are configured to cause the return loss at the output to be than 10 decibels (dB) in the second frequency spectrum.

15. The filter circuit of claim 10 , further comprising means for increasing the return loss at the input in the second frequency spectrum.

16. The filter circuit of claim 15 , wherein the return loss is substantially the same at the input and the output.

17. The filter circuit of claim 16 , wherein the return loss is substantially the same at the input and the output due to symmetry of the filter circuit.

18. The filter circuit of claim 10 , wherein the means for increasing the return loss comprises:
a first high pass portion;
a second high pass portion; and
an attenuator portion comprising one or more resistors, wherein the attenuator portion is connected in series between the first and second high pass portions.

19. A filter circuit, comprising:
a pass band filter portion configured to pass signals in a first frequency spectrum and attenuate or block signals in a second frequency spectrum, wherein the second frequency spectrum is higher than the first frequency spectrum, and wherein the pass band filter portion is configured to cause a return loss of more than 10 decibels (dB) in the first frequency spectrum.

20. The filter circuit of claim 1 , wherein the interference mitigation portion comprises:
a first high pass portion configured to be connected to the pass band filter portion;
a second high pass portion; and
an attenuator portion comprising one or more resistors, wherein the attenuator portion is connected in series between the first and second high pass portions.

21. The filter circuit of claim 19 , wherein the return loss is at an output of the filter circuit.

22. The filter circuit of claim 19 , wherein the pass band filter portion is configured to cause the return loss to be more than 10 decibels (dB) in the second frequency spectrum.

23. The filter circuit of claim 22 , wherein the return loss is at an output of the filter circuit.

24. The filter circuit of claim 19 , wherein the pass band filter portion is configured to cause an ins

Assignees

• Ppc Broadband Inc

Inventors

• Alkan Erdogan
• Palinkas Raymond W

Classifications

• H03H7/01

  Frequency selective two-port networks · CPC title

• H03H7/0138

  Electrical filters or coupling circuits · CPC title

• H03H7/1741

  Comprising typical LC combinations, irrespective of presence and location of additional resistors (when resistors are present, also classify in H03H7/06 - H03H7/07) · CPC title

• H03H7/0161 Primary

  Bandpass filters (H03H7/12 takes precedence) · CPC title

• H03H7/06

  including resistors (H03H7/075, H03H7/09, H03H7/12, H03H7/13 take precedence) · CPC title