Adaptive air interface waveform

• US 6,847,678 B2
• Filed: 04/22/2003
• Issued: 01/25/2005
• Est. Priority Date: 04/25/2002
• Status: Expired due to Term

• Current Assignee: Raytheon Company (Rtx Corporation)
• Original Assignee: Raytheon Company (Rtx Corporation)
• Inventors: Berezdivin, Roberto, Breinig, Robert J., Topp, Allan R., Seidel, Scott Y.
• Primary Examiner(s): TSE, YOUNG TOI
• Application Number:
  US10/421,168
• Publication Number:
  US 20030203721A1
• Time in Patent Office: 644 Days
• Field of Search: 375/132, 375/133, 375/135, 375/136, 375/138, 375/140, 375/141, 375/146, 375/147, 370/335, 370/337, 370/342, 370/343, 370/344, 370/347, 370/429, 370/480, 370/482, 370/491
• US Class Current: 375/146
• CPC Class Codes: H03M 13/1102 Codes on graphs and decoding on graphs, e.g. low-density parity check [LDPC] codes
• CPC Class Codes: H03M 13/255 with Low Density Parity Check [LDPC] codes
• CPC Class Codes: H04L 1/0001 Systems modifying transmission characteristics according to link quality, e.g. power backoff adaptive data allocation for multicarrier modulation H04L5/0044; controlling transmission power for radio systems H04W52/04
• CPC Class Codes: H04L 1/0002 by adapting the transmission rate
• CPC Class Codes: H04L 1/0009 by adapting the channel coding H04L1/1812 takes precedence
• CPC Class Codes: H04L 5/0021 in which codes are applied as a frequency-domain sequences, e.g. MC-CDMA
• CPC Class Codes: H04L 5/0037 Inter-user or inter-terminal allocation
• CPC Class Codes: H04L 5/0042 intra-user or intra-terminal allocation
• CPC Class Codes: H04L 5/0046 Determination of how many bits are transmitted on different sub-channels
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04L 5/006 Quality of the received signal, e.g. BER, SNR, water filling
• CPC Class Codes: H04L 5/0064 Rate requirement of the data, e.g. scalable bandwidth, data priority

Abstract

In one embodiment, a method for generating an adaptive air interface waveform includes generating a waveform that includes a variable carrier frequency and variable bandwidth signal. The variable bandwidth signal includes one or more subcarriers that are dynamically placeable over a range of frequencies, and each subcarrier is separately modulated according to a direct sequence (DS) spread spectrum (SS) technique. The waveform has an embedded pilot usable to optimize one or more spectrum efficiencies of the waveform. A modulation constellation, a code rate, and a code length of the generated waveform are adapted according to an available spectrum and one or more sub-carrier conditions.

Claims

1. A system for generating an adaptive air interface waveform, the system comprising:

an adaptive multi-carrier organization and signaling component operable to generate a waveform having a multi-carrier organization comprising a variable carrier frequency and variable bandwidth signal that comprises one or more subcarriers that are dynamically placeable over a range of frequencies, each subcarrier being separately modulated according to a direct sequence (DS) spread spectrum (SS) modulation technique, the waveform having an embedded pilot usable to optimize one or more spectrum efficiencies of the waveform; and

an adaptive multi-level bandwidth-efficient coding and modulation (BECM) component receive the waveform from the adaptive multi-carrier organization and signaling component, the BECM component operable to adapt a modulation constellation, a code rate, and a code length of the waveform according to an available spectrum and one or more varying conditions of the subcarrier in order to provide the waveform as the adaptive air interface waveform.

2. The system of claim 1, wherein the waveform is a heteromorphic waveform operable to dynamically adapt with respect to one or more of frequency, time, modulation, code, data rate, power, signaling, and multi-carrier organization.

3. The system of claim 1, wherein the range of frequencies spans approximately 250 MHz.

4. The system of claim 1, wherein the waveform is operable to use one or more unused holes in a spectrum defined by one or more of frequency, space, and time.

5. The system of claim 1, wherein the waveform supports a plurality of multiple access (MA) modulation techniques.

6. The system of claim 5, wherein the plurality of MA modulation techniques comprises:

one or more carrier division multiple access (CDMA) modulation techniques;

one or more time division multiple access (TDMA) modulation techniques;

one or more frequency division multiple access (FDMA) modulation techniques;

one or more frequency-hopped multiple access (FHMA) modulation techniques.

7. The system of claim 5, wherein at least one of the MA modulation techniques is a hybrid MA modulation technique that combines two or more different conventional modulation techniques.

8. The system of claim 1, wherein the BECM uses a low-density parity-check (LDPC) code modulation technique to adapt the modulation constellation, the code rate, and the code length of the waveform.

9. The system of claim 1, wherein the BECM is operable to adapt the modulation constellation, the code rate, and the code length of the waveform according to one or more quality of service (QoS) requirements and one or more data rate requirements for signal transport, in addition to the available spectrum and one or more varying conditions of the subcarrier.

10. The system of claim 1, wherein the waveform exhibits both macroscopic frequency agility and microscopic frequency agility.

11. A method for generating an adaptive air interface waveform, the method comprising:

generating a waveform having a multi-carrier organization comprising a variable carrier frequency and variable bandwidth signal that comprises one or more subcarrier that are dynamically placeable over a range of frequencies, each subcarrier being separately modulated according to a direct sequence (DS) spread spectrum (SS) modulation technique, the waveform having an embedded pilot usable to optimize one or more spectrum efficiencies of the waveform; and

adapting a modulation constellation, a code rate, and a code length of the waveform according to an available spectrum and one or more varying conditions of the subcarrier in order to provide the waveform as the adaptive air interface waveform.

12. The method of claim 11, wherein the waveform is a heteromorphic waveform operable to dynamically adapt with respect to one or more of frequency, time, modulation, code, data rate, power, signaling, and multi-carrier organization.

13. The method of claim 11, wherein the range of frequencies spans approximately 250 MHz.

14. The method of claim 11, wherein the waveform is operable to use one or more unused holes in a spectrum defined by one or more of frequency, space, and time.

15. The method of claim 11, wherein the waveform supports a plurality of multiple access (MA) modulation techniques.

16. The method of claim 15, wherein the plurality of MA modulation techniques comprises:

one or more carrier division multiple access (CDMA) modulation techniques;

one or more time division multiple access (TDMA) modulation techniques;

one or more frequency division multiple access (FDMA) modulation techniques;

one or more frequency-hopped multiple access (FHMA) modulation techniques.

17. The method of claim 15, wherein at least one of the MA modulation techniques is a hybrid MA modulation technique that combines two or more different conventional modulation techniques.

18. The method of claim 11, wherein a low-density parity-check (LDPC) code modulation technique is used to adapt the modulation constellation, the code rate, and the code length of the waveform.

19. The method of claim 11, wherein the modulation constellation, the code rate, and the code length of the waveform is adapted according to one or more quality of service (QoS) requirements and one or more data rate requirements for signal transport, in addition to the available spectrum and one or more varying conditions of the subcarrier.

20. The method of claim 11, wherein the waveform exhibits both macroscopic frequency agility and microscopic frequency agility.

21. Software for generating an adaptive air interface waveform, the software embodied in media and when executed operable to:

generate a waveform having a multi-carrier organization comprising a variable carrier frequency and variable bandwidth signal that comprises one or more subcarriers that are dynamically placeable over a range of frequencies, each subcarrier being separately modulated according to a direct sequence (DS) spread spectrum (SS) modulation technique, the waveform having an embedded pilot usable to optimize one or more spectrum efficiencies of the waveform; and

adapt a modulation constellation, a code rate, and a code length of the waveform according to a available spectrum and one or more varying conditions of the subcarrier in order to provide the waveform as the adaptive air interface waveform.

22. The software of claim 21, wherein the waveform is a heteromorphic waveform operable to dynamically adapt with respect to one or more of frequency, time, modulation, code, data rate, power, signaling, and multi-carrier organization.

23. The software of claim 21, wherein the range of frequencies spans approximately 250 MHz.

24. The software of claim 21, wherein the waveform is operable to use one or more unused holes in a spectrum defined by one or more of frequency, space, and time.

25. The software of claim 21, wherein the waveform supports a plurality of multiple access (MA) modulation techniques.

26. The software of claim 25, wherein the plurality of MA modulation techniques comprises:

one or more carrier division multiple access (CDMA) modulation techniques;

one or more time division multiple access (TDMA) modulation techniques;

one or more frequency division multiple access (FDMA) modulation techniques;

one or more frequency-hopped multiple access a (FHMA) modulation techniques.

27. The software of claim 25, wherein at least one of the MA modulation techniques is a hybrid MA modulation technique that combines two or more different conventional modulation techniques.

28. The software of claim 21, wherein a low-density parity-check (LDPC) code modulation technique is used to adapt the modulation constellation, the code rate, and the code length of the waveform.

29. The software of claim 21, wherein the modulation constellation, the code rate, and the code length of the waveform is adapted according to one or more quality of service (QoS) requirements and one or more data rate requirements for signal transport, in addition to the available spectrum and one or more varying conditions of the subcarrier.

30. The software of claim 21, wherein the waveform exhibits both macroscopic frequency agility and microscopic frequency agility.

31. A system for generating an adaptive air interface waveform, the system comprising:

means for generating a waveform having a multi-carrier organization comprising a variable carrier frequency and variable bandwidth signal that comprises on or more subcarriers that are dynamically placeable over a range of frequencies, each subcarrier being separately modulated according to a direct sequence (DS) spread spectrum (SS) modulation technique, the waveform having an embedded pilot usable to optimize one or more spectrum efficiencies of the waveform; and

means for receiving the waveform from the means for generating the waveform and adapting a modulation constellation, a code rate, and a code length of the waveform according to an available spectrum and one or more varying conditions of the subcarrier in order to provide the waveform as the adaptive air interface waveform.