Multi-input multi-output tuner front ends

• US 20050195335A1
• Filed: 07/02/2004
• Published: 09/08/2005
• Est. Priority Date: 02/13/2004
• Status: Active Grant

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Broadcom Corporation (Broadcom, Inc.)
• Inventors: Dauhinee, Leonard, Gomez, Ramon A., Brooks, Charles
• Granted Patent: US 7,701,515 B2
• Time in Patent Office: Days
• US Class Current: 348/707
• CPC Class Codes: H04N 21/4263 involving specific tuning arrangements, e.g. two tuners
• CPC Class Codes: H04N 5/46 for receiving on more than one standard at will deflecting circuits of multi-standard receivers H04N3/27
• CPC Class Codes: H04N 5/50 Tuning indicators; Automatic tuning control

Abstract

A front end circuit for a television receiver includes a demultiplexer for inputting a multi-band signal from a signal source and separating the multi-band signal into corresponding bands. A plurality of amplifiers adjust gain on signals corresponding to the bands. A multiplexer combines outputs of the amplifiers into a gain-adjusted signal. A plurality of switches direct selected bands to corresponding tuners. The amplifiers are low noise amplifiers. The amplifiers adjust gain between the bands so as to have similar signal strength in the bands. A cable TV input may also be used, wherein the switches also direct signals from the cable TV to the corresponding tuners. Each amplifier can output two (or more) identical signals for its corresponding band, the multiplexer can be a dual multiplexer, and an output of the multiplexer includes only bands selected for direction to the tuners. The signal source comprises any of an broadcast channel received from an antenna, a cable TV channel received from a cable line, and a combination of the two.

Claims

1. A front end circuit for a television receiver comprising:

a demultiplexer for inputting a multi-band signal from a signal source and separating the multi-band signal into corresponding bands;

a plurality of amplifiers for adjusting gain on signals corresponding to the bands;

a multiplexer combining outputs of the amplifiers into a gain-adjusted signal; and

a plurality of switches directing selected bands to corresponding tuners.

2. The circuit of claim 1, wherein the amplifiers are low noise amplifiers.

3. The circuit of claim 1, wherein the amplifiers adjust gain between the bands so as to have similar signal strength in the bands.

4. The circuit of claim 1, further including a cable TV input, wherein the switches also direct signals from the cable TV input to the corresponding tuners.

5. The circuit of claim 1, wherein each amplifier outputs two identical signals for its corresponding band,

wherein the multiplexer is a dual multiplexer, and

wherein an output of the multiplexer comprises only bands selected for direction to the tuners.

6. The circuit of claim 1, wherein the signal source comprises any of an broadcast channel received from an antenna, a cable TV channel received from a cable line, and a combination of the two.

7. The circuit of claim 6, further comprising a diplexer receiving an upstream signal from a cable TV subscriber equipment and directing it to a cable TV headend.

8. A front end circuit for a television receiver comprising:

a demultiplexer separating a multi-band signal into corresponding bands;

a plurality of amplifiers adjusting gain on signals corresponding to the bands;

a multiplexer forming a gain-adjusted signal from outputs of the amplifiers; and

a plurality of switches directing selected bands to corresponding tuners.

9. The circuit of claim 8, wherein the amplifiers are low noise amplifiers.

10. The circuit of claim 8, wherein the amplifiers adjust gain between the bands so as to have similar signal strength in the bands.

11. The circuit of claim 8, further including a cable TV input, wherein the switches also direct signals from the cable TV input to the corresponding tuners.

12. The circuit of claim 8, wherein each amplifier outputs two identical signals for its corresponding band,

wherein the multiplexer is a dual multiplexer, and

wherein an output of the multiplexer comprises only bands selected for direction to the tuners.

13. The circuit of claim 8, wherein the signal source comprises any of an broadcast channel received from an antenna, a cable TV channel received from a cable line, and a combination of the two.

14. The circuit of claim 13, further comprising a diplexer receiving an upstream signal from a cable TV subscriber equipment and directing it to a cable TV headend.

15. A method of processing a signal comprising:

inputting a multi-band signal from a signal source;

separating the multi-band signal into corresponding bands;

adjusting gain on signals corresponding to the bands;

combining outputs of the amplifiers into a gain-adjusted signal; and

directing selected bands to corresponding tuners.

16. The circuit of claim 15, wherein the adjusting step adjusts gain between the bands so as to have similar signal strength in the bands.

17. The circuit of claim 15, wherein the directing step also direct signals from a cable TV input to the corresponding tuners.

18. The circuit of claim 15, further comprising outputting two identical signals for each corresponding band.

19. The circuit of claim 15, wherein the signal source comprises any of an broadcast channel received from an antenna, a cable TV channel received from a cable line, and a combination of the two.