APPARATUS AND METHOD FOR INTERFERENCE-ADAPTIVE COMMUNICATIONS

• US 20100062705A1
• Filed: 09/10/2008
• Published: 03/11/2010
• Est. Priority Date: 09/10/2008
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Huang, Yuheng, Rajkotia, Amol, Dural, Ozgur
• Granted Patent: US 8,355,666 B2
• Time in Patent Office: Days
• US Class Current: 455/1
• CPC Class Codes: H04K 3/224 with countermeasures at transmission and/or reception of the jammed signal, e.g. stopping operation of transmitter or receiver, nulling or enhancing transmitted power in direction of or at frequency of jammer
• CPC Class Codes: H04L 1/0071 Use of interleaving interleaving per se H03M13/27
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/0044 allocation of payload
• CPC Class Codes: H04L 5/006 Quality of the received signal, e.g. BER, SNR, water filling

Abstract

In embodiments, an adaptive tone erasure technique is applied to orthogonal frequency division multiplexing (OFDM) communications, such as ECMA-368 standard ultra-wideband (UWB) communications. A transmitter obtains jammed sub-carrier information and calculates an erasure mask. The jammed sub-carriers are nulled before transmitting to a receiver. In accordance with the erasure mask, bits falling on the jammed sub-carriers are replaced by erasure bits before interleaving, keeping the interleaver block size constant notwithstanding variations in the number of the jammed sub-carriers. The receiver also obtains the jammed sub-carrier information and the erasure mask. After the receiver deinterleaves the constant size blocks, it decodes the data without the erasure bits. The transmitter may detect the jammed sub-carriers itself, or obtain the information from the receiver. The receiver similarly may detect the jammed sub-carriers itself, or obtain the information from the transmitter.

Claims

1. A communication method comprising:

obtaining at a transmitter device current jammed sub-carrier information identifying currently jammed sub-carriers of a plurality of sub-carriers available for carrying data from the transmitter device to a receiver device;

obtaining at the transmitter device an erasure mask corresponding to the current jammed sub-carrier information;

inserting erasure bits into each of a plurality of data sub-blocks processed in accordance with the erasure mask to obtain sub-blocks of a predetermined size;

interleaving each sub-block of the sub-blocks of the predetermined size to obtain interleaved sub-blocks, the erasure bits being located in the sub-blocks of a predetermined size so that the erasure bits fall onto the currently jammed sub-carriers; and

transmitting wirelessly the interleaved sub-blocks from the transmitter device.

2. The method of claim 1, further comprising:

nulling out the currently jammed sub-carriers before transmitting.

3. The method of claim 1, wherein obtaining current jammed sub-carrier information comprises receiving the information from the receiver device.

4. The method of claim 3, wherein obtaining current jammed sub-carrier information is performed periodically with a predetermined time interval.

5. The method of claim 3, wherein obtaining current jammed sub-carrier information is performed at times determined by dynamically varying interference affecting communications between the transmitter device and the receiver device.

6. The method of claim 3, wherein obtaining current jammed sub-carrier information comprises receiving at the transmitter device one or more predetermined messages comprising the information.

7. The method of claim 1, wherein obtaining current jammed sub-carrier information comprises determining the information locally at the transmitter device.

8. The method of claim 1, wherein obtaining current jammed sub-carrier information comprises:

sending a jammed sub-carrier query to the receiver device; and

in response to the jammed sub-carrier query, receiving from the receiver device the jammed sub-carrier information.

9. The method of claim 1, further comprising:

mapping bits of the interleaved sub-blocks into modulated symbols, the step of mapping being performed before the step of transmitting.

10. The method of claim 1, wherein:

transmitting is performed in accordance with ECMA-368 standard and the sub-carriers of the plurality of sub-carriers are orthogonal frequency division multiplexed (OFDM) sub-carriers.

11. The method of claim 10, wherein:

obtaining the erasure mask comprises step for obtaining the erasure mask so that the erasure bits fall onto the currently jammed sub-carriers.

12. The method of claim 10, wherein obtaining the erasure mask comprises:

generating a complete physical null tone list {P_n, n=1, 2, . . . , N_in};

generating a data null tone list {Q_n, n=1, 2, . . . , N_in} by converting each P_n to Q_n using tone mapping rule defined by the ECMA-368 standard;

for each Q_n, generating

$\left(\frac{6}{N_{\mathrm{TDS}}}\right)$

pairs of integers according to rule;

{2Q_n, 2Q_n+1}+k·

N_CBPS, k=0, 1, . . . , (6/N_TDS−

1);

stacking the integers into a list {q_n};

for each entry in the list {q_n}, reverse-calculating the step of interleaving to obtain integers q_n⁽³⁾; and

stacking the integers q_n⁽³⁾ into a list {q_n⁽³⁾} to obtain the erasure mask, wherein the integers q_n⁽³⁾ indicate indices for inserting the erasure bits.

13. A transmitter device comprising:

a memory;

a wireless receiver;

a wireless transmitter; and

a controller coupled to the wireless receiver, the wireless transmitter, and the memory, the controller being configured to;

obtain at the transmitter device current jammed sub-carrier information identifying currently jammed sub-carriers of a plurality of sub-carriers available for carrying data from the transmitter device to a receiver device,

obtain at the transmitter device an erasure mask corresponding to the current jammed sub-carrier information,

insert erasure bits into each of a plurality of sub-blocks processed in accordance with the erasure mask to obtain sub-blocks of a predetermined size,

interleave each sub-block of the sub-blocks of the predetermined size to obtain interleaved sub-blocks, the erasure bits being located in the sub-blocks of a predetermined size so that the erasure bits fall onto the currently jammed sub-carriers, and

communicate the interleaved sub-blocks to the wireless transmitter for transmission.

14. The transmitter device of claim 13, wherein further comprise:

nulling out the currently jammed sub-carriers before the step of transmitting.

15. The transmitter device of claim 13, wherein obtaining current jammed sub-carrier information comprises receiving the information from the receiver device.

16. The transmitter device of claim 15, wherein obtaining current jammed sub-carrier information periodically with a predetermined time interval.

17. The transmitter device of claim 15, wherein obtaining current jammed sub-carrier information at times determined by dynamically varying interference affecting communications between the transmitter device and the receiver device.

18. The transmitter device of claim 15, wherein obtaining current jammed sub-carrier information comprises receiving at the transmitter device one or more vendor-specific messages comprising the information.

19. The transmitter device of claim 13, wherein obtaining current jammed sub-carrier information comprises determining the information locally at the transmitter device.

20. The transmitter device of claim 13, further comprising:

mapping bits of the interleaved sub-blocks into modulated symbols, mapping being performed before transmitting.

21. The transmitter device of claim 13, wherein:

the wireless transmitter is configured to transmit in accordance with ECMA-368 standard;

the wireless receiver is configured to receive in accordance with the ECMA-368 standard; and

the transmitting is performed in accordance with the ECMA-368 standard and the sub-carriers of the plurality of sub-carriers are orthogonal frequency division multiplexed (OFDM) sub-carriers.

22. The transmitter device of claim 21, wherein:

obtaining the erasure mask comprises step for computing the erasure mask so that the erasure bits fall onto the currently jammed sub-carriers.

23. The transmitter device of claim 21, wherein obtaining the erasure mask comprises:

generating a complete physical null tone list {P_n, n=1, 2, . . . , N_in};

generating a data null tone list {Q_n, n=1, 2, . . . , N_in} by converting each P_n to Q_n using tone mapping rule defined by the ECMA-368 standard;

for each Q_n, generating

$\left(\frac{6}{N_{\mathrm{TDS}}}\right)$

pairs of integers according to rule;

{2Q_n, 2Q_n+1}+k·

N_CBPS, k=0, 1, . . . , (6/N_TDS−

1);

stacking the integers into a list {q_n};

for each entry in the list {q_n}, reverse-calculating the step of interleaving to obtain integers q_n⁽³⁾; and

stacking the integers q_n⁽³⁾ into a list {q_n⁽³⁾} to obtain the erasure mask, wherein the integers q_n⁽³⁾ indicate indices for inserting the erasure bits.

24. A transmitter device comprising:

a means for storing data;

a means for wirelessly receiving;

a means for wirelessly transmitting; and

a means for processing coupled to the means for receiving, the means for transmitting, and the means for storing, the means for processing being configured to;

obtain at the transmitter device current jammed sub-carrier information identifying currently jammed sub-carriers of a plurality of sub-carriers available for carrying data from the transmitter device to a receiver device,

obtain at the transmitter device an erasure mask corresponding to the current jammed sub-carrier information,

insert erasure bits into each sub-block processed in accordance with the erasure mask to obtain sub-blocks of a predetermined size,

interleave each sub-block of the sub-blocks of the predetermined size to obtain interleaved sub-blocks, the erasure bits being located in the sub-blocks of predetermined size so that the erasure bits fall onto the currently jammed sub-carriers, and

communicate the interleaved sub-blocks to the wireless transmitter for transmission.

25. A computer program product comprising:

computer-readable medium comprising;

code for causing a computer to obtain at the transmitter device current jammed sub-carrier information identifying currently jammed sub-carriers of a plurality of sub-carriers available for carrying data from the transmitter device to a receiver device;

code for causing a computer to obtain at the transmitter device an erasure mask corresponding to the current jammed sub-carrier information;

code for causing a computer to insert erasure bits into each sub-block processed in accordance with the erasure mask to obtain sub-blocks of a predetermined size;

code for causing a computer to interleave each sub-block of the sub-blocks of the predetermined size to obtain interleaved sub-blocks, the erasure bits located in the sub-blocks of predetermined size so that the erasure bits fall onto the currently jammed sub-carriers; and

code for causing a computer to communicate the interleaved sub-blocks to a transmitter for transmission from the transmitter device.

26. A communication method comprising steps of:

obtaining at a receiver device current jammed sub-carrier information identifying currently jammed sub-carriers of a plurality of sub-carriers available for carrying data from a transmitter device to the receiver device;

obtaining at the receiver device an erasure mask corresponding to the current jammed sub-carrier information;

receiving at the receiver device interleaved sub-blocks from the transmitter device, the interleaved sub-blocks having a predetermined size, the interleaved sub-blocks comprising erasure bits inserted in accordance with the erasure mask;

deinterleaving each interleaved sub-block of the interleaved sub-blocks to obtain deinterleaved sub-blocks;

removing the erasure bits from the deinterleaved sub-blocks in accordance with the erasure mask to obtain processed sub-blocks wherein the erasure bits are located in the sub-blocks so that the erasure bits fall onto the currently jammed sub-carriers; and

decoding the processed sub-blocks.

27. The method of claim 26, further comprising:

nulling out the currently jammed sub-carriers before the step of deinterleaving.

28. The method of claim 26, wherein obtaining current jammed sub-carrier information comprises receiving the information from the transmitter device.

29. The method of claim 28, wherein obtaining current jammed sub-carrier information is performed periodically with a predetermined time interval.

30. The method of claim 28, wherein obtaining current jammed sub-carrier information is performed at times determined by dynamically varying interference affecting communications between the transmitter device and the receiver device.

31. The method of claim 28, wherein obtaining current jammed sub-carrier information comprises receiving at the receiver device one or more pre-determined messages comprising the information.

32. The method of claim 26, wherein obtaining current jammed sub-carrier information comprises determining the information locally at the receiver device.

33. The method of claim 26, further comprising:

demodulating the interleaved sub-blocks.

34. The method of claim 26, wherein:

receiving is performed in accordance with ECMA-368 standard and the sub-carriers of the plurality of sub-carriers are orthogonal frequency division multiplexed (OFDM) sub-carriers.

35. The method of claim 34, wherein:

obtaining the erasure mask comprises step for obtaining the erasure mask so that the erasure bits fall onto the currently jammed sub-carriers.

36. The method of claim 34, wherein obtaining the erasure mask comprises:

generating a complete physical null tone list {P_n, n=1, 2, . . . , N_in};

generating a data null tone list {Q_n, n=1, 2, . . . , N_in} by converting each P_n to Q_n using tone mapping rule defined by the ECMA-368 standard;

for each Q_n, generating

$\left(\frac{6}{N_{\mathrm{TDS}}}\right)$

pairs of integers according to rule;

{2Q_n, 2Q_n+1}+k·

N_CBPS, k=0, 1, . . . , (6/N_TDS−

1);

stacking the integers into a list {q_n};

for each entry in the list {q_n}, reverse-calculating the step of interleaving to obtain integers q_n⁽³⁾; and

stacking the integers q_n⁽³⁾ into a list {q_n⁽³⁾} to obtain the erasure mask, wherein the integers q_n⁽³⁾ indicate indices for inserting the erasure bits.

37. The method of claim 26, further comprising:

transmitting the current jammed sub-carrier information from the receiver device to the transmitter device.

38. The method of claim 26, further comprising:

transmitting the erasure mask from the receiver device to the transmitter device.

39. A receiver device comprising:

a memory;

a wireless receiver;

a wireless transmitter; and

a controller coupled to the wireless receiver, the wireless transmitter, and the memory, the controller configured to;

obtain current jammed sub-carrier information identifying currently jammed sub-carriers of a plurality of sub-carriers available for carrying data from a transmitter device to the receiver device,

obtain an erasure mask corresponding to the current jammed sub-carrier information,

receive interleaved sub-blocks from the transmitter device, the interleaved sub-blocks having a predetermined size, the interleaved sub-blocks comprising erasure bits inserted in accordance with the erasure mask,

deinterleave each interleaved sub-block of the interleaved sub-blocks to obtain deinterleaved sub-blocks,

remove the erasure bits from the deinterleaved sub-blocks in accordance with the erasure mask to obtain processed sub-blocks wherein the erasure bits are located in the sub-blocks so that the erasure bits fall onto the currently jammed sub-carriers, and

decode the processed sub-blocks.

40. The receiver device of claim 39, wherein the controller is further configured to null out the currently jammed sub-carriers before deinterleaving.

41. The receiver device of claim 39, wherein obtaining current jammed sub-carrier information comprises receiving the information from the transmitter device.

42. The receiver device of claim 41, wherein obtaining current jammed sub-carrier information is performed periodically with a predetermined time interval.

43. The receiver device of claim 41, wherein obtaining current jammed sub-carrier information is performed at times determined by dynamically varying interference affecting communications between the transmitter device and the receiver device.

44. The receiver device of claim 41, wherein obtaining current jammed sub-carrier information comprises receiving at the receiver device one or more vendor-specific messages comprising the information.

45. The receiver device of claim 39, wherein obtaining current jammed sub-carrier information comprises determining the information locally at the receiver device.

46. The receiver device of claim 39, further comprising:

a demodulator configured to demodulate the interleaved sub-blocks.

47. The receiver device of claim 39, wherein:

the wireless receiver is configured to communicate in accordance with the ECMA-368 standard;

the wireless transmitter is configured to communicate in accordance with ECMA-368 standard; and

receiving is performed in accordance with the ECMA-368 standard and the sub-carriers of the plurality of sub-carriers are orthogonal frequency division multiplexed (OFDM) sub-carriers.

48. The receiver device of claim 47, wherein:

obtaining the erasure mask comprises step for computing the erasure mask so that the erasure bits fall onto the currently jammed sub-carriers.

49. The receiver device of claim 47, wherein obtaining the erasure mask comprises:

generating a complete physical null tone list {P_n, n=1, 2, . . . , N_in};

generating a data null tone list {Q_n, n=1, 2, . . . , N_in} by converting each P_n to Q_n using tone mapping rule defined by the ECMA-368 standard;

for each Q_n, generating

$\left(\frac{6}{N_{\mathrm{TDS}}}\right)$

pairs of integers according to rule;

{2Q_n, 2Q_n+1}+k·

N_CBPS, k=0, 1, . . . , (6/N_TDS−

1);

stacking the integers into a list {q_n};

for each entry in the list {q_n}, reverse-calculating the step of interleaving to obtain integers q_n⁽³⁾; and

stacking the integers q_n⁽³⁾ into a list {q_n⁽³⁾} to obtain the erasure mask, wherein the integers q_n⁽³⁾ indicate indices for inserting the erasure bits.

50. The receiver device of claim 39, further comprising:

The controller communicating the current jammed sub-carrier information to the wireless transmitter for transmission.

51. The receiver device of claim 39, further comprising:

the controller communicating the erasure mask to the wireless transmitter for transmission.

52. A receiver device comprising:

a means for storing data;

a means for wirelessly receiving;

a means for wirelessly transmitting; and

a means for processing coupled to the means for receiving, the means for transmitting, and the means for storing, the means for processing being configured to;

obtain current jammed sub-carrier information identifying currently jammed sub-carriers of a plurality of sub-carriers available for carrying data from a transmitter device to the receiver device,

obtain an erasure mask corresponding to the current jammed sub-carrier information,

receive interleaved sub-blocks from the transmitter device, the interleaved sub-blocks having a predetermined size, the interleaved sub-blocks comprising erasure bits inserted in accordance with the erasure mask,

deinterleave each interleaved sub-block of the interleaved sub-blocks to obtain deinterleaved sub-blocks,

remove the erasure bits from the deinterleaved sub-blocks in accordance with the erasure mask to obtain processed sub-blocks wherein the erasure bits are located in the sub-blocks so that the erasure bits fall onto the currently jammed sub-carriers, and

decode the processed sub-blocks.

53. A computer program product comprising:

computer-readable medium comprising;

code for causing a computer to obtain at the wireless receiver device current jammed sub-carrier information identifying currently jammed sub-carriers of a plurality of sub-carriers available for carrying data from a wireless transmitter device to the wireless receiver device;

code for causing a computer to obtain at the wireless receiver device an erasure mask corresponding to the current jammed sub-carrier information;

code for causing a computer to receive at the wireless receiver device interleaved sub-blocks from the wireless transmitter device, the interleaved sub-blocks having a predetermined size, the interleaved sub-blocks comprising erasure bits inserted in accordance with the erasure mask;

code for causing a computer to deinterleave each interleaved sub-block of the interleaved sub-blocks to obtain deinterleaved sub-blocks;

code for causing a computer to remove the erasure bits from the deinterleaved sub-blocks in accordance with the erasure mask to obtain processed sub-blocks, the erasure bits being located in the sub-blocks so that the erasure bits fall onto the currently jammed sub-carriers; and

code for causing a computer to decode the processed sub-blocks;

wherein the step of obtaining the erasure mask is performed so that the erasure bits fall onto the currently jammed sub-carriers.