Data communication system and method

• US 6,259,728 B1
• Filed: 06/08/1999
• Issued: 07/10/2001
• Est. Priority Date: 06/08/1999
• Status: Expired due to Term

• Current Assignee: RPX Corporation
• Original Assignee: Lucent Technologies, Inc. (Nokia Corporation)
• Inventors: Shelby, Kevin A., Sharma, Ramautar
• Primary Examiner(s): Pham, Chi
• Assistant Examiner(s): PHU, PHUONG M
• Application Number:
  US09/328,082
• Time in Patent Office: 763 Days
• Field of Search: 375/222, 375/223, 375/260, 375/261, 375/267, 370/204, 370/208, 370/210, 370/484, 370/487, 370/436, 370/478, 370/330, 341/111
• US Class Current: 375/223
• CPC Class Codes: H04L 27/0008 arrangements for allowing a transmitter or receiver to use more than one type of modulation negotiating modulation type for two-way transmission paths H04L5/1453

Abstract

Disclosed is a system and method for modulating and demodulating a data signal. The system includes a number of configurable multi-rate signal processing modules coupled to a local interface. The system also includes a control module coupled to the local interface, the control module being adapted to shuttle a number of data symbols among the configurable multi-rate processing modules according to a predefined modulation or demodulation scheme. The system can advantageously be configured to perform one of multiple modulation or demodulation schemes.

Claims

1. A configurable modem circuit for modulating/demodulating a data signal, comprising:

a plurality of configurable multi-rate signal processing modules coupled to a local interface, each of the configurable multi-rate processing modules comprising;

a first sample rate converte;

;

a first digital filter coupled to the first sample rate converter;

a second sample rate converter; and

a second digital filter coupled to the second sample rate converter and also coupled to the first digital filter;

a first one of the multi-rate signal processing modules being configured to process a data signal in accordance with a first modulation/demodulation scheme, a second one of the multi-rate signal processing modules being configured to process a data signal in accordance with a second modulation/demodulation scheme, the first modulation/demodulation scheme being different than the second modulation/demodulation scheme; and

a control module coupled to the local interface, the control module being adapted to shuttle a number of data symbols among the configurable multi-rate processing modules according to a predefined modulation/demodulation scheme such that, in response to receiving a data signal corresponding to the first modulation/demodulation scheme, the controller shuttles data symbols to the first one of the multi-rate signal processing modules for processing and, in response to receiving a data signal corresponding to the second modulation/demodulation scheme, the controller shuttles data symbols to the second one of the multi-rate signal processing modules for processing.

2. The circuit of claim 1, wherein the configurable multi-rate signal processing modules are synthesis modules configured to generate a modulated data signal from a number of data symbols.

3. The circuit of claim 1, wherein the configurable multi-rate signal processing modules are analysis modules configured to recover a number of data symbols from a modulated data signal.

4. The circuit of claim 1, further comprising at least one mapper coupled to the local interface.

5. The circuit of claim 1, further comprising a configurable mapper coupled to the local interface, the configurable mapper being configured to receive a stream of input data symbols and, in response to receiving a first configuration signal corresponding to the first modulation/demodulation scheme, mapping the stream of input data symbols into a stream of in-phase data symbols and a stream of quadrature data symbols corresponding to the first modulation/demodulation scheme and, in response to receiving a second configuration signal corresponding to the second modulation/demodulation scheme, mapping the stream of input data symbols into a stream of in-phase data symbols and a stream of quadrature data symbols corresponding to the second modulation/demodulation scheme.

6. The circuit of claim 1, further comprising at least one de-mapper coupled to the local interface.

7. The circuit of claim 1, further comprising a configurable de-mapper coupled to the local interface, the configurable de-mapper being configured to receive a stream of in-phase data symbols and a stream of quadrature data symbols and, in response to receiving a first de-configuration signal corresponding to the first modulation/demodulation scheme, de-mapping the stream of in-phase data symbols and the stream of quadrature data symbols into a stream of input data symbols corresponding to the first modulation/demodulation scheme and, in response to receiving a second deconfiguration signal corresponding to the second modulation/demodulation scheme, de-mapping the stream of in-phase data symbols and the stream of quadrature data symbols into a stream of input data symbols corresponding to the second modulation/demodulation scheme.

8. The circuit of claim 1, further comprising a summing junction coupled to the local interface.

9. A configurable modem circuit for modulating/demodulating a data signal, comprising:

a number of configurable multi-rate signal processing modules, each of the configurable multi-rate processing modules comprising;

a first sample rate converter;

a first digital filter coupled to the first sample rate converter;

a second sample rate converter; and

a second digital filter coupled to the second sample rate converter and also coupled to the first digital filter;

a first one of the multi-rate signal processing modules being configured to process a data signal in accordance with a first modulation/demodulation scheme, a second one of the multi-rate signal processing modules being configured to process a data signal in accordance with a second modulation/demodulation scheme, the first modulation/demodulation scheme being different than the second modulation/demodulation scheme; and

means for shuttling a number of data symbols among the configurable multi-rate signal processing modules according to either of the first or second modulation/demodulation schemes.

10. The system of claim 9, further comprising a means for mapping a stream of data symbols into at least one stream of quadrature data symbols and at least one stream of in-phase data symbols.

11. The system of claim 9, further comprising a means for performing an addition of a quadrature component and an in-phase component of a data signal.

12. A system for modulating a data signal for transmission over a communications channel, comprising:

a configurable input mapper coupled to a local interface, the input mapper having a data input;

a control module coupled to the local interface;

a buffer memory coupled to the local interface;

a number of synthesis modules coupled to the local interface, a first one of the synthesis modules being configured to process a data signal in accordance with a first modulation scheme, a second one of the synthesis modules being configured to process a data signal in accordance with a second modulation scheme, the first modulation scheme being different than the second modulation scheme; and

an output summing node coupled to the local interface, the output summing node having a modulated data outputs,

the control module being adapted to shuttle a number of data symbols among the synthesis modules such that, in response to receiving a data signal corresponding to the first modulation scheme, the controller shuttles data symbols to the first one of the synthesis modules for processing and, in response to receiving a data signal corresponding to the second modulation scheme, the controller shuttles data symbols to the second one of the synthesis modules for processing.

13. The system of claim 12, wherein each of the synthesis modules further comprise:

a first sample rate converter;

a first digital filter coupled to the first sample rate converter;

a second sample rate converter;

a second digital filter coupled to the second sample rate converter; and

a summing junction coupled to the first and second digital filters.

14. The system of claim 12, wherein the control module further comprises a state machine.

15. The system of claim 12, wherein the control module further comprises:

a processor;

a local memory; and

a data distribution logic stored on the memory, wherein the data distribution logic is executed by the processor.

16. The system of claim 12, wherein the configurable mapper further comprises a carrierless amplitude/phase mapping circuit.

17. The system of claim 12, wherein the configurable mapper further comprises a multi-channel mapping circuit.

18. The system of claim 12, wherein the configurable mapper further comprises a discrete wavelet mapping circuit.

19. A system for modulating a data signal for transmission over a communications channel, comprising:

means for mapping a number of data symbols in a data signal;

means for shuttling a number of mapped data signals among a number of synthesis modules;

means for processing the mapped data signals in the synthesis modules such that a first one of the synthesis modules is configured to process a data signal in accordance with a first modulation scheme and a second one of the synthesis modules is configured to process a data signal in accordance with a second modulation scheme, the first modulation scheme being different than the second modulation scheme; and

means for summing a number of quadrature symbols and a number of in-phase symbols generated by the synthesis modules to generate a modulated data output signal,

the means for shuttling being configured such that, in response to receiving a data signal corresponding to the first modulation scheme, the means for shuttling shuttles data symbols to the first one of the synthesis modules for processing and, in response to receiving a data signal corresponding to the second modulation scheme, the means for shuttling shuttles data symbols to the second one of the synthesis modules for processing.

20. A method for modulating a data signal for transmission over a communications channel, comprising the steps of:

mapping a number of data symbols in a data signal;

shuttling a number of mapped data signals among a number of synthesis modules such that, in response to receiving a data signal corresponding to the first modulation scheme, data symbols are shuttled to the first one of the synthesis modules for processing and, in response to receiving a data signal corresponding to the second modulation scheme, data symbols are shuttled to the second one of the synthesis modules for processing;

processing the mapped data signals in the synthesis modules such that, a first one of the synthesis modules processes a data signal in accordance with a first modulation scheme, and a second one of the synthesis modules processes a data signal in accordance with a second modulation scheme, the first modulation scheme being different than the second modulation scheme such that, in response to receiving a data signal corresponding to the first modulation scheme, the first one of the synthesis modules processes the mapped data signals and, in response to receiving a data signal corresponding to the second modulation scheme, the second one of the synthesis modules processes the mapped data signals; and

summing a number of quadrature symbols and a number of in-phase symbols generated by the synthesis modules to generate a modulated data output signal.

21. The method of claim 20, wherein the step of processing the mapped data signals in the synthesis modules further comprises the steps of:

up-converting a first sample rate of a first mapped data signal;

digitally filtering the first mapped data signal;

up-converting a second sample rate of a second mapped data signal;

digitally filtering the second mapped data signal; and

summing the first and second mapped data signals.

22. A system for demodulating a data signal transmitted over a communications channel, comprising:

an input buffer coupled to a local interface;

a control module coupled the local interface;

a buffer memory coupled to the local interface;

a number of analysis modules coupled to the local interface, a first one of the analysis modules being configured to process quadrature and in-phase symbols in accordance with a first demodulation scheme, a second one of the analysis modules being configured to process quadrature and in-phase symbols in accordance with a second demodulation scheme, the first demodulation scheme being different than the second demodulation scheme; and

a configurable de-mapper coupled to the local interface,

the control module being adapted to shuttle a number of quadrature and in-phase symbols among the analysis modules such that, in response to receiving a data signal corresponding to the first demodulation scheme, the controller shuttles quadrature and in-phase symbols to the first one of the analysis modules for processing and, in response to receiving a data signal corresponding to the second demodulation scheme, the controller shuttles quadrature and in-phase symbols to the second one of the analysis modules for processing.

23. The system of claim 22, wherein each of the analysis modules further comprise:

a first digital filter and a second digital filter coupled to a common input node;

a first sample rate down-converter coupled to the first digital filter; and

a second sample rate down-converter coupled to the second digital filter.

24. The system of claim 22, wherein the control module further comprises a state machine.

25. The system of claim 22, wherein the control module further comprises:

a processor;

a local memory; and

a data distribution logic stored on the memory, wherein the data distribution logic is executed by the processor.

26. The system of claim 22, wherein the configurable de-mapper further comprises:

a carrierless amplitude/phase de-mapping circuit;

a multi-channel de-mapping circuit; and

a discrete wavelet de-mapping circuit.

27. A system for demodulating a data signal transmitted over a communications channel, comprising:

means for generating a number of quadrature symbols and a number of in-phase symbols from a modulated data signal;

means for shuttling the quadrature and in-phase symbols among a number of analysis modules;

means for processing the quadrature and in-phase symbols in the analysis modules such that a first one of the analysis modules is configured to process quadrature and in-phase symbols in accordance with a first demodulation scheme and a second one of the analysis modules is configured to process quadrature and in-phase symbols in accordance with a second demodulation scheme, the first demodulation scheme being different than the second demodulation scheme; and

means for de-mapping the quadrature and in-phase symbols, thereby recovering an original data signal,

the means for shuttling being adapted to shuttle a number of quadrature and in-phase symbols among the analysis modules such that, in response to receiving a data signal corresponding to the first demodulation scheme, the means for shuttling shuttles quadrature and in-phase symbols to the first one of the analysis modules for processing and, in response to receiving a data signal corresponding to the second demodulation scheme, the means for shuttling shuttles quadrature and in-phase symbols to the second one of the analysis modules for processing.

28. A method for demodulating a data signal transmitted over a communications channel, comprising the steps of:

generating a number of quadrature symbols and a number of in-phase symbols from a modulated data signal;

shuttling the quadrature and in-phase symbols among a number of analysis modules such that, a first one of the analysis modules processes quadrature and in-phase symbols in accordance with a first demodulation scheme, and a second one of the analysis modules processes quadrature and in-phase symbols in accordance with a second demodulation scheme, the first demodulation scheme being different than the second demodulation scheme;

processing the quadrature and in-phase symbols in the analysis modules; and

de-mapping the quadrature and in-phase symbols, thereby recovering an original data signal.

29. The method of claim 28, wherein the step of processing the quadrature and in-phase symbols in the analysis modules further comprises the steps of:

filtering a symbol input with a first digital filter and a second digital filter, the first and second digital filters being in parallel;

down-converting a first sample rate of the output of the first digital filter; and

down-converting a second sample rate of the output of the second digital filter.