Multi-channel communications transceiver

• US 20030134607A1
• Filed: 12/04/2002
• Published: 07/17/2003
• Est. Priority Date: 07/11/2001
• Status: Active Grant

• Current Assignee: Entropic Communications, LLC (FIG LLC (d/b/a Fortress Investment Group LLC))
• Original Assignee: Entropic Communications Incorporated (Maxlinear Incorporated)
• Inventors: Raghavan, Sreeen A., Sallaway, Peter J., Taylor, Gerard E., Manickam, Thulasinath G.
• Granted Patent: US 7,403,752 B2
• Time in Patent Office: Days
• US Class Current: 455/132
• CPC Class Codes: H04L 27/2601 Multicarrier modulation systems

Abstract

A transceiver system according to the present invention transmits data utilizing the baseband and one or more frequency separated transmission bands. A baseband transmitter is combined with one or more transmitters that transmit data into one of the frequency separated transmission bands. A baseband receiver is combined with one or more receivers that receive data from the frequency separated transmission bands. Any combination of modulation systems can be utilized (e.g. PAM for the baseband and QAM for the frequency separated bands). A transceiver circuit or chip according to the present invention includes a transmitter and a receiver and communicates with a corresponding transceiver chip. In some embodiments, one baseband PAM transmitter is combined with one frequency separated QAM transmitter.

Claims

1. A transmission system, comprising:

a baseband receiver to receiver a baseband signal from a transmitted signal; and

one or more down-converting receivers that receive a signal in the transmitted signal that was transmitted in a corresponding one or more frequency separated transmission band.

2. The system of claim 1, wherein at least one of the down-converting receivers comprises:

a down converter that converts the signal from the transmitted signal from the one of the plurality of transmission bands to a base band;

a filter coupled to receive signals from the down converter, the filter substantially filtering out signals not in the base band;

an analog-to-digital converter coupled to receive signals from the filter and generate digitized signals;

an equalizer coupled to receive the digitized signals.

3. The system of claim 2, wherein the down-converter creates an in-phase signal and a quadrature signal, the in-phase signal being the input signal multiplied by a cosine function at the frequency of the one of the plurality of transmission bands and the quadrature signal being the input signal multiplied by a sine function at the frequency of the one of the plurality of transmission bands.

4. The system of claim 2, wherein operating parameters of at least one of the down converter, the filter, the analog-to-digital converter, and the equalizer are adaptively chosen.

5. The system of claim 1, wherein the baseband receiver includes

an analog processing circuit to receive an input signal;

an analog-to-digital converter coupled to receive signals from the low-pass filter; and

a data recovery block coupled to receive signals from the analog-to-digital converter.

6. The system of claim 5, wherein the analog processing circuit includes a low-pass filter.

7. The system of claim 5, wherein the analog processing circuit includes an amplifier.

8. The system of claim 5, wherein the analog processing circuit includes an offset.

9. The system of claim 5, wherein the analog processing circuit receives adaptively chosen parameters from an adaptive parameter control circuit.

10. The system of claim 5, wherein a digital circuit is coupled between the analog to digital converter and the data recovery circuit.

11. The system of claim 10, wherein the digital circuit includes a digital gain block.

12. The system of claim 10, wherein the digital circuit includes a digital base-line correction block.

13. The system of claim 10, wherein the digital circuit includes an equalizer.

14. The system of claim 13, wherein the equalizer includes a decision feedback equalizer.

15. The system of claim 13, wherein the equalizer includes a linear equalizer.

16. The system of claim 10, wherein the digital circuit receives at least one parameter that is adaptively chosen in an adaptive parameter control circuit.

17. The system of claim 5, wherein the data recovery circuit is a slicer.

18. The system of claim 5, wherein the data recovery circuit includes a forward error correction decoding circuit.

19. The system of claim 18, wherein the forward error correction decoding circuit is a trellis decoder.

20. The system of claim 18, wherein the forward error correction decoding circuit is a Reed-Solomon decoding circuit.

21. The system of claim 4, further including a descrambler circuit coupled to receive signals from the data recovery circuit.

22. The system of claim 1, further including a cross-channel interference correction circuit coupled between the one or more down-converting receivers.

23. The system of claim 22 wherein the cross-channel interference correction circuit corrects for interference between transmissions in the baseband and transmissions in the frequency separated transmission bands.

24. The system of claim 22 wherein the cross-channel interference correction circuit is further coupled to the baseband receiver to correct transmissions in the baseband for interference from transmissions in the frequency separated transmission bands.

25. The system of claim 1, further including

a baseband transmitter that transmits data into the baseband;

and

one or more up-converting transmitters that transmit data into one of the frequency separated transmission bands.

26. The system of claim 25, wherein at least one of the up-converting transmitters includes

a symbol mapper coupled to map a set of digital inputs to a symbol;

and

an up-conversion circuit coupled to form a transmission signal from the symbol at a carrier frequency.

27. The system of claim 25, further including a summer wherein the output signal from the up-converting transmitters is summed to form a sum signal.

28. The system of claim 27, further including a second summer wherein the sum signal is summed with an output signal from the baseband transmitter to form the transmitted signal.

29. The system of claim 28, further including a high-pass filter coupled between the summer and the second summer to filter any base-band contribution out of the sum signal.

30. The system of claim 28, further including a low-pass filter coupled between the baseband transmitter and the second summer to filter any higher frequency component from the output signal from the baseband transmitter.

31. A method of transmitting data, comprising:

receiving a transmitted signal from a transmission medium into a baseband receiver and one or more down-converting receivers;

each of the down-converting receivers down-converting the transmission signal by a set carrier frequency to obtain a data signal for that down-converting receiver; and

the baseband receiver receiving a data signal from the baseband of the transmitted signal.

32. The method of claim 31, further including

forming a baseband signal in a baseband transmitter;

forming one or more frequency separated signals in one or more up-converting transmitters;

summing the baseband signal with the one or more frequency separated signals to form a sum signal; and

transmitting the sum signal over the transmission medium to form the transmitted signal.

33. The method of claim 32, further including filtering a sum of the one or more frequency separated signals with a high pass filter before summing.

34. The method of claim 32, further including filtering the baseband signal with a low pass filter before summing.

35. The method of claim 31, further including correcting for cross-channel interference.

36. The method of claim 35, wherein correcting for cross-channel interference includes correcting for interference between the down-converting receivers.

37. The method of claim 35, wherein correcting for cross-channel interference includes correcting for interference between the down-converting receivers and the baseband receiver.

38. The method of claim 35, wherein correcting for cross-channel interference includes:

receiving equalized signals from two or more of the baseband receiver and the down-converting receivers; and

subtracting components of the equalized signals from two or more of the baseband receiver and the down-converting receivers.

39. The method of claim 38, wherein subtracting components of the equalized signals includes providing a transfer function between each pair of the two or more of the baseband receiver and the down-converting receivers.

40. The method of claim 39 wherein coefficients of the transfer function are adaptively chosen.

41. A transmission system, comprising:

means for transmitting data into the baseband and one or more frequency separated transmission bands on a transmission medium;

means for receiving data from the transmission medium.

44. The transceiver chip of claim 41, wherein the transmitter section includes a low-pass filter coupled to the base-band transmitter, a high-pass filter coupled to receive a summed output signal from the one or more up-converting transmitters, and a summer coupled to sum signals from the low-pass filter and the high-pass filter.

45. The transceiver chip of claim 41, wherein the baseband transmitter is a PAM transmitter.

46. The transceiver chip of claim 41, wherein the one or more up-converting transmitters includes a QAM transmitter.

47. The transceiver chip of claim 41, wherein the baseband transmitter is an 8-PAM transmitter with no error correction coding and the one or more up-converting transmitters are each 6/7 trellis encoded 128 QAM.

48. The transceiver chip of claim 41, wherein the baseband transmitter is a 16-PAM transmitter and the one or more up-converting transmitter includes a 16-QAM transmitter.

49. The transceiver chip of claim 41, wherein the baseband transmitter is a 16 PAM transmitter and the one or more up-converting transmitter includes a 32-QAM transmitter.

50. The transceiver chip of claim 41, wherein the baseband transmitter is a 3/4 encoded 16 PAM transmitter and the one or more up-converting transmitter includes a 6/7 encoded 128-QAM transmitter.

42. A transceiver chip, comprising:

a transmitter section, the transmitter section including

a baseband transmitter that transmits data onto a transmission medium in a baseband channel, and

one or more up-converting transmitters that transmits data onto the transmission medium in corresponding frequency separated channels;

a receiver section, the receiver section including

a baseband receiver that receives data from the transmission medium in the baseband channel, and

one or more down-converting receivers that receive data from the transmission medium from the corresponding frequency separated channels.

43. The transceiver chip of claim 42, wherein the receiver section includes a cross-channel interference correction circuit.