Multichannel Digital Cable Tuner

• US 20090174822A1
• Filed: 06/16/2006
• Published: 07/09/2009
• Est. Priority Date: 06/16/2006
• Status: Active Grant

• Current Assignee: InterDigital Madison Patent Holdings (InterDigital, Inc.)
• Original Assignee: Thomson Licensing (Vantiva SA)
• Inventors: Pugel, Michael Anthony
• Granted Patent: US 8,902,369 B2
• Time in Patent Office: Days
• US Class Current: 348/731
• CPC Class Codes: H04N 21/426 Internal components of the client ; Characteristics thereof H04N5/44 takes precedence
• CPC Class Codes: H04N 21/42607 for processing the incoming bitstream
• CPC Class Codes: H04N 21/4347 Demultiplexing of several video streams
• CPC Class Codes: H04N 21/4382 Demodulation or channel decoding, e.g. QPSK demodulation analog front ends or means for connecting modulators, demodulators or transceivers to a transmission line H04L27/0002
• CPC Class Codes: H04N 5/46 for receiving on more than one standard at will deflecting circuits of multi-standard receivers H04N3/27

Abstract

A method and apparatus is presented for simultaneous reception of a plurality of digital RF channels. Specifically, N amplifier-filter circuits are configured to receive and separate a multichannel analog RF input signal into N analog signals, each including a different frequency band. N analog-to-digital converters are provided, each respectively coupled to one of the N amplifier-filter circuits and configured to receive an analog signal and generate a respective digital signal. A digital tuner is coupled to receive and demultiplex the N digital signals generated by the N analog-to-digital converters thereby recovering M digital RF channels. M demodulation circuits are provided for performing demodulation and forward-error-correction of the M digital RF channels (see FIG. 1). This combination of components permits substantially simultaneous reception of multiple digital cable channels within a single digital receiver circuit suitable for use with conventional cable delivery systems and at a reasonable cost.

Claims

1. An apparatus, comprising:

first means for processing an input signal comprising signals in a first frequency band and signals in a second frequency band to produce a first analog signal including signals in the first frequency band and substantially excluding the signals in the second frequency band;

second means for processing the input signal comprising

signals in a first frequency band and signals in a second frequency band to produce a second analog signal including signals in the second frequency band and substantially excluding the signals in the first frequency band;

a first analog-to-digital converter for processing the first analog signal to produce a first digital signal representing the signals in the first frequency band;

a second analog-to-digital converter for processing the second analog signal to produce a second digital signal representing the signals in the second frequency band; and

a means for processing the first and second digital signals to simultaneously produce a first output signal representing a first digital channel included in the first frequency band and a second output signal representing a second digital channel included in the second frequency band.

2. The apparatus of claim 1 further comprising a third amplifier-filter circuit configured to process signals within a third frequency band and a third analog-to-digital converter configured generate a third digital signal comprising a representation of said processed signals within said third frequency band.

3. The apparatus of claim 2 wherein said first frequency band includes frequencies from about 5 MHz to about 300 MHz, said second band includes frequencies between about 300 MHz and about 600 MHz, and said third band includes frequencies from about 600 MHz to about 900 MHz.

4. The apparatus of claim 3 wherein said first second and third analog-to-digital converters have sampling frequencies of at least 600 MHz.

5. The apparatus of claim 3 wherein said first second and third analog-to-digital converters are configured for an input frequency of up to about 900 MHz.

6. The apparatus of claim 1 wherein the digital processor (130) includes a frequency selector for selecting a desired sampling frequency.

7. The apparatus of claim 1 wherein each of said first, second, and third analog-to-digital converters have a resolution of at least about 10 bits.

8. The apparatus of claim 1 wherein each of said first, second, and third analog-to-digital converters have a resolution from about 10 to about 16 bits.

9. The apparatus of claim 1 wherein said digital processor is configured to recover substantially all signals with said first and second frequency bands.

10. The apparatus of claim 1 wherein said digital processor is configured to recover a selected set of signals with said first and second frequency bands.

11. The apparatus of claim 10 wherein said digital processor is configured to recover said selected set of signals with said first and second frequency bands substantially simultaneously.

12. The apparatus of claim 1 further comprising a first demodulator circuit coupled to said digital processor and a second demodulator circuit coupled to said digital processor

13. The apparatus of claim 12 wherein said first and second demodulator circuits include circuitry configured for forward error correction

14. The apparatus of claim 12 where said digital processor multiplexes said first, second, and third digital signals, downconverts said multiplexed signal and extracts desired information to be coupled to said first and second demodulator circuits.

15. The apparatus of claim 12 where said digital processor downconverts and extracts desired information to be coupled to said first and second demodulator circuits (141, 142) from each of said first, second, and third digital signals individually.

16. The apparatus of claim 1 wherein said apparatus processes frequencies between about 5 MHz and about 900 MHz.

17. The apparatus of claim 1 wherein apparatus processes cable television channels.

18. A method processing signals comprising the steps of:

(a) separating an input signal into a first analog signal and a second analog signal;

(b) digitizing said first analog signal to generate a first digital signal;

(c) digitizing said second analog signal to generate a second digital signal;

(d) downconverting said first digital signal and said second signal; and

(e) extracting desired television program information from said downconverted first digital signal and said second digital signal.

19. The method of claim 18, further comprising the steps of:

(a) demodulating said extracted television program information;

(b) forward-error-correcting said extracted television program information;

20. The method of claim 18 further comprising the steps of:

(a) multiplexing said first digital signal and said second digital signal after said digitizing steps and before said downconverting step.

21. The method of claim 18 further where said downconverting step comprises downconverting each of said first and second set of signals individually.