Frequency hopping communication device and frequency hopping method

• US 6,658,044 B1
• Filed: 06/22/2000
• Issued: 12/02/2003
• Est. Priority Date: 06/23/1999
• Status: Expired due to Term

• Current Assignee: Hanwha Systems Co., Ltd.
• Original Assignee: Samsung Thomson-CSF Co., Ltd. (Hanwha Corporation)
• Inventors: Kim, Je-Woo, Park, Jong-Hyeon, Cho, Hyung-Weon
• Primary Examiner(s): PHU, PHUONG M
• Application Number:
  US09/602,201
• Time in Patent Office: 1,258 Days
• Field of Search: 375/132, 375/133, 375/134, 375/135
• US Class Current: 375/135
• CPC Class Codes: H04B 1/713 using frequency hopping
• CPC Class Codes: H04L 5/023 Multiplexing of multicarrier modulation signals multicarrier modulation H04L27/2601

Abstract

A frequency hopping (FH) communication device and a frequency hopping method are provided. The frequency hopping communication device includes a first frequency hopping unit for receiving data to be transmitted, orthogonal frequency division multiplexing (OFDM) modulating the received data using the frequency of a subcarrier corresponding to a first frequency hopping code among the frequencies of a predetermined number of subcarriers, and outputting first frequency hopped data on which the data to be transmitted is loaded and a second frequency hopping unit for second frequency hopping the first frequency hopped data by mixing the first frequency hopped data with a carrier composed according to a second frequency hopping code. When jamming occurs, the frequency affected by jamming is restricted to a narrow bandwidth. Therefore, it is possible to reduce the influence of jamming and to easily restore data even though jamming occurs. Also, it is possible to improve the degree of concealment of data.

Claims

1. A communication apparatus, comprising:

a first unit receiving first data, generating a first frequency hopping code, generating first frequency hopped data in dependence upon said first frequency hopping code, modulating said first frequency hopped data, outputting said modulated data, said modulating corresponding to orthogonal frequency division multiplexing modulating, said modulated data corresponding to said received first data loaded on said first frequency hopped data; and

a second unit receiving input data corresponding to said modulated data, generating a second frequency hopping code, composing carrier data in dependence upon said second frequency hopping code, mixing said composed data with said input data, and outputting second frequency hopped data corresponding to said mixing of said composed data with said input data, said received first data corresponding to data to be transmitted.

2. The apparatus of claim 1, said first frequency hopping code being generated when said first data is received by said first unit, said second frequency hopping code being generated when said input data is received by said second unit.

3. The apparatus of claim 1, said first frequency hopping code corresponding to a predetermined first frequency hopping code, said second frequency hopping code corresponding to a predetermined second frequency hopping code.

4. The apparatus of claim 1, said first frequency hopping code being generated in accordance with first predetermined regulations, said second frequency hopping code being generated in accordance with second predetermined regulations.

5. The apparatus of claim 1, said first frequency hopping code being generated in accordance with first predetermined regulations when said first data is received by said first unit, said second frequency hopping code being generated in accordance with second predetermined regulations when said input data is received by said second unit.

6. The apparatus of claim 1, said first frequency hopping code being generated in accordance with first predetermined regulations when said first data is received by said first unit, said first frequency hopping code corresponding to a predetermined first frequency hopping code, said second frequency hopping code being generated in accordance with second predetermined regulations when said input data is received by said second unit, said second frequency hopping code corresponding to a predetermined second frequency hopping code.

7. The apparatus of claim 1, said modulating of said first frequency hopped data using a frequency of a predetermined subcarrier.

8. The apparatus of claim 1, said modulating of said first frequency hopped data using a frequency of a subcarrier corresponding to said first frequency hopping code among frequencies of a predetermined quantity of subcarriers.

9. The apparatus of claim 1, said apparatus corresponding to a frequency hopping communication device frequency hopping data.

10. The apparatus of claim 1, said first unit corresponding to a first frequency hopping unit, said second unit corresponding to a second frequency hopping unit.

11. The apparatus of claim 1, said first unit generating said first frequency hopped data in dependence upon said received first data and said first frequency hopping code.

12. The apparatus of claim 1, said first unit comprising:

a first frequency hopping code generator performing said generating of said first frequency hopping code according to predetermined regulations when said first data is received by said first unit;

a first frequency hopping data storage unit performing said generating of said first frequency hopped data; and

an orthogonal-frequency-division-multiplexing modulator performing said modulating of said first frequency hopped data using a frequency of a predetermined subcarrier, and performing said outputting of said modulated data.

13. The apparatus of claim 12, said first frequency hopping code corresponding to a predetermined first frequency hopping code.

14. The apparatus of claim 12, said predetermined subcarrier being among a predetermined quantity of subcarriers.

15. The apparatus of claim 14, further comprising:

a guard interval inserting unit receiving said modulated data output from said modulator, inserting a guard interval into said modulated data, said guard interval reducing influence of intersymbol interference and interframe interference between said predetermined quantity of subcarriers.

16. The apparatus of claim 15, further comprising:

a digital-to-analog converter converting data output from said guard interval inserting unit into analog data, and outputting said converted analog data.

17. The apparatus of claim 16, said second unit comprising:

a second frequency hopping code generator performing said generating of said second frequency hopping code according to predetermined regulations when said input data is received by said second unit; and

a second frequency hopping data generator performing said composing of said carrier data, performing said mixing of said composed data with said received input data, and generating said second frequency hopped data, said received input data corresponding to said analog data output from said the digital-to-analog converter.

18. The apparatus of claim 15, said second unit comprising:

a second frequency hopping code generator performing said generating of said second frequency hopping code according to predetermined regulations when said input data is received by said second unit; and

a second frequency hopping data generator performing said composing of said carrier data, performing said mixing of said composed data with said received input data, and generating said second frequency hopped data.

19. The apparatus of claim 12, further comprising:

a digital-to-analog converter converting said modulated data output from said first unit into analog data, and outputting said converted analog data.

20. The apparatus of claim 19, said second unit comprising:

a second frequency hopping code generator performing said generating of said second frequency hopping code according to predetermined regulations when said input data is received by said second unit; and

a second frequency hopping data generator performing said composing of said carrier data, performing said mixing of said composed data with said received input data, and generating said second frequency hopped data, said received input data corresponding to said analog data output from said the digital-to-analog converter.

21. The apparatus of claim 12, said second unit comprising:

a second frequency hopping code generator performing said generating of said second frequency hopping code according to predetermined regulations when said input data is received by said second unit; and

a second frequency hopping data generator performing said composing of said carrier data, performing said mixing of said composed data with said received input data, and generating said second frequency hopped data.

22. The apparatus of claim 1, said first unit performing said modulating of said first frequency hopped data using a frequency of a predetermined subcarrier, said predetermined subcarrier being among a predetermined quantity of subcarriers.

23. The apparatus of claim 22, further comprising:

a guard interval inserting unit receiving said modulated data output from said first unit, inserting a guard interval into said modulated data, said guard interval reducing influence of intersymbol interference and interframe interference between said predetermined quantity of subcarriers.

24. The apparatus of claim 23, further comprising:

a digital-to-analog converter converting data output from said guard interval inserting unit into analog data, and outputting said converted analog data.

25. The apparatus of claim 24, said second unit comprising:

a second frequency hopping code generator performing said generating of said second frequency hopping code according to predetermined regulations when said input data is received by said second unit; and

a second frequency hopping data generator performing said composing of said carrier data, performing said mixing of said composed data with said received input data, and generating said second frequency hopped data, said received input data corresponding to said analog data output from said the digital-to-analog converter.

26. The apparatus of claim 25, said second frequency hopping code corresponding to a predetermined second frequency hopping code.

27. The apparatus of claim 23, said second unit comprising:

a second frequency hopping code generator performing said generating of said second frequency hopping code according to predetermined regulations when said input data is received by said second unit; and

a second frequency hopping data generator performing said composing of said carrier data, performing said mixing of said composed data with said received input data, and generating said second frequency hopped data.

28. The apparatus of claim 27, said second frequency hopping code corresponding to a predetermined second frequency hopping code.

29. The apparatus of claim 1, further comprising:

a digital-to-analog converter converting said modulated data output from said first unit into analog data, and outputting said converted analog data.

30. The apparatus of claim 29, said second unit comprising:

a second frequency hopping code generator performing said generating of said second frequency hopping code according to predetermined regulations when said input data is received by said second unit; and

a second frequency hopping data generator performing said composing of said carrier data, performing said mixing of said composed data with said received input data, and generating said second frequency hopped data, said received input data corresponding to said analog data output from said the digital-to-analog converter.

31. The apparatus of claim 1, said second unit comprising:

a second frequency hopping code generator performing said generating of said second frequency hopping code according to predetermined regulations when said input data is received by said second unit; and

a second frequency hopping data generator performing said composing of said carrier data, performing said mixing of said composed data with said received input data, and generating said second frequency hopped data.

32. The apparatus of claim 31, said second frequency hopping code corresponding to a predetermined second frequency hopping code.

33. A frequency hopping communication apparatus, comprising:

a first unit receiving first data, generating a predetermined first frequency hopping code, generating first frequency hopped data in dependence upon said first frequency hopping code, modulating said first frequency hopped data, outputting said modulated data, said modulated data corresponding to said received first data loaded on said first frequency hopped data; and

a second unit receiving input data corresponding to said modulated data, generating a predetermined second frequency hopping code, composing carrier data in dependence upon said second frequency hopping code, mixing said composed data with said input data, and outputting second frequency hopped data corresponding to said mixing of said composed data with said input data, said first data received by said first unit corresponding to data to be transmitted.

34. The apparatus of claim 33, said modulating corresponding to orthogonal frequency division multiplexing modulating.

35. The apparatus of claim 34, said first frequency hopping code comprising:

frequency information for orthogonal-frequency-division-multiplexing modulating said received first data using N predetermined subcarriers, where N is a predetermined positive number.

36. The apparatus of claim 35, said first unit comprising:

a first frequency hopping data storage unit outputting said first frequency hopped data;

a first converter first converting said first frequency hopped data into a determined number of data items, and outputting said first converted data, said first converter corresponding to a serial-to-parallel converter, said first converting corresponding to parallel converting, said first converted data corresponding to parallel converted data, said first converted data corresponding to d_p(t);

a second converter second converting said first converted data using frequencies of said N predetermined subcarriers, orthogonal-frequency-division-multiplexing modulating said first converted data, and outputting said first converted data loaded on N modulated subcarriers, said second converter corresponding to an N-point complex inverse-fast-Fourier-transform converter, said second converting corresponding to N-point complex inverse-fast-Fourier-transform converting, said N modulated subcarriers corresponding to d_i(n); and

a third converter receiving said N subcarrier data output from said second converter, third converting said received N subcarrier data, and outputting said third converted data, said third converter corresponding to a parallel-to-serial converter, said third converting corresponding to serially converting.

37. The apparatus of claim 36, said frequencies of said N predetermined subcarriers being determined to be different from each other according to said first frequency hopping code used by said first unit.

38. The apparatus of claim 37, said second converter outputting said second converted data by N-point complex inverse-fast-Fourier-transform converting said first converted data in accordance with $d_i$

 



(n)=1N

 



∑

k=0N-1

 



dp

 



(t)

 





j

 



2

 



π



 



nk/N,

wherein n=1, 2, 3, . . . , and d_p(t) corresponding to said parallel converted data, and d_i(n) corresponding to said N modulated subcarriers outputted.

39. The apparatus of claim 38, said N subcarriers having phases being orthogonal to each other.

40. The apparatus of claim 33, said first unit comprising:

a first converter receiving said first data, first converting said received first data into a predetermined number of data items, and outputting said first converted data, said first converter corresponding to a serial-to-parallel converter, said first converting corresponding to parallel converting;

a first frequency hopping data storage unit receiving said first converted data, and outputting said first frequency hopped data;

a first frequency hopping code generator generating said predetermined first frequency hopping code in accordance with specified regulations when said first converted data are input to said first frequency hopping data storage unit;

a second converter orthogonal-frequency-division-multiplexing modulating said first frequency hopping data using frequencies of N predetermined subcarriers and outputting N modulated subcarriers on which said first converted data are loaded, said second converter corresponding to an N-point complex inverse-fast-Fourier-transform converter; and

a third converter receiving said N subcarrier data output from said second converter, third converting said received N subcarrier data, and outputting said third converted data, said third converter corresponding to a parallel-to-serial converter, said third converting corresponding to serially converting.

41. The apparatus of claim 40, said frequencies of said N subcarriers being determined to be different in accordance with said first frequency hopping code used by said first unit.

42. The apparatus of claim 40, said second converter outputting said second converted data by N-point complex inverse-fast-Fourier-transform converting said first converted data in accordance with $d_i$

 



(n)=1N

 



∑

k=0N-1

 



dp

 



(t)

 





j

 



2

 



π



 



nk/N,

wherein n=1, 2, 3, . . . , and d_p(t) corresponding to said first converted data, and d_i(n) correspoding to said N modulated subcarriers outputted.

43. The apparatus of claim 40, said first frequency hopping code generator comprising:

a pseudo noise code generator generating a pseudo noise code for said frequency hopped data to be transmitted, outputting said pseudo noise code;

an address generator generating an address corresponding to said pseudo noise code, outputting said address; and

a memory receiving and storing said first data, outputting said first frequency hopping code corresponding to said address, said memory storing said first frequency hopping code.

44. The apparatus of claim 40, said first frequency hopping code generator comprising:

a pseudo noise code generator generating a pseudo noise code;

an address generator generating an address corresponding to said pseudo noise code; and

a memory outputting said first frequency hopping code corresponding to said address when said first data is received by said first unit.

45. The apparatus of claim 33, said first unit comprising:

a first frequency hopping code generator performing said generating of said first frequency hopping code according to predetermined regulations when said first data is received by said first unit;

a first frequency hopping data storage unit performing said generating of said first frequency hopped data; and

an orthogonal-frequency-division-multiplexing modulator performing said modulating of said first frequency hopped data using a frequency of a predetermined subcarrier, and performing said outputting of said modulated data.

46. The apparatus of claim 45, said first frequency hopping code generator comprising:

a pseudo noise code generator generating a pseudo noise code for said frequency hopping said first data, outputting said pseudo noise code;

an address generator generating an address corresponding to said pseudo noise code, outputting said address; and

a memory receiving and storing said first data, outputting said first frequency hopping code corresponding to said address, said memory storing said first frequency hopping code.

47. The apparatus of claim 45, said first frequency hopping code generator comprising:

a pseudo noise code generator generating a pseudo noise code;

an address generator generating an address corresponding to said pseudo noise code; and

a memory outputting said first frequency hopping code corresponding to said address when said first data is received by said first unit.

48. The apparatus of claim 33, said first unit comprising:

a pseudo noise code generator generating a pseudo noise code for said frequency hopped data to be transmitted, outputting said pseudo noise code;

an address generator generating an address corresponding to said pseudo noise code, outputting said address; and

a memory receiving and storing said first data, outputting said first frequency hopping code corresponding to said address, said memory storing said first frequency hopping code.

49. A method, comprising:

modulating first data using a frequency of a subcarrier corresponding to a predetermined first frequency hopping code, said frequency being selected from among a plurality of frequencies of a predetermined number of subcarriers, said first data corresponding to data to be transmitted;

outputting first frequency hopped data on which said first data is loaded, said first frequency hopped data on which said first data is loaded corresponding to modulated data; and

second frequency hopping said first frequency hopped data by mixing said first frequency hopped data with a subcarrier composed in dependence upon a second frequency hopping code.

50. The method of claim 49, said modulating corresponding to orthogonal-frequency-division-multiplexing modulating.

51. The method of claim 50, said modulating further comprising:

generating said predetermined first frequency hopping code according to specified regulations when said first data is input to a first unit;

combining said first frequency hopping code with said first data, outputting second data, said second data corresponding to data to be hopped; and

dividing said second data into said first data and said first frequency hopping code, orthogonal-frequency-division-multiplexing modulating said first data using said frequency of said subcarrier corresponding to said first frequency hopping code.

52. The method of claim 51, further comprising:

receiving said modulated data and inserting a guard interval into said modulated data, said guard interval reducing influence of intersymbol interference and interframe interference, said modulated data having said guard interval inserted corresponding to guard interval data, said receiving being performed after said dividing.

53. The method of claim 52, said guard interval reducing influence of intersymbol interference and interframe interference between said predetermined number of subcarriers.

54. The method of claim 52, further comprising:

converting said guard interval data into analog data, outputting said analog data, said converting being performed after said receiving.

55. The method of claim 54, said second frequency hopping further comprising:

generating a predetermined second frequency hopping code in dependence upon specified regulations when said analog data is input to a second unit;

composing said subcarrier data of a frequency corresponding to said second frequency hopping code; and

mixing said analog data with said composed data, generating second frequency hopped data.

56. The method of claim 50, said predetermined first frequency hopping code including frequency information for orthogonal-frequency-division-multiplexing modulating said first data using N predetermined subcarriers when N is a predetermined positive number.

57. The method of claim 50, said modulating further comprising:

outputting second data corresponding to said first frequency hopping code, said second data corresponding to first frequency hopped data;

parallel converting said first frequency hopped data into a predetermined number of data items and outputting said parallel converted data, said parallel converted data corresponding to d_p(t);

N-point complex inverse-fast-Fourier-transform converting said parallel converted data using frequencies of N predetermined subcarriers, orthogonal-frequency-division-multiplexing modulating said parallel converted data, outputting N modulated subcarriers on which said parallel converted data are loaded, said N modulated subcarriers corresponding to d_i(n); and

receiving said N subcarrier data output from said N-point complex inverse-fast-Fourier-transform converter, serially converting said subcarrier data, outputting said serially converted data.

58. The method of claim 57, said frequencies of said N predetermined subcarriers being determined to be different from each other according to said first frequency hopping code used by said first unit.

59. The method of claim 57, said receiving of said N subcarrier data output from said inverse-fast-Fourier-transform converter, said serially converting of said subcarrier data, said outputting of said serially converted data comprising:

obtaining said data d_i(n) by N-point complex inverse-fast-Fourier-transform converting said first data according to $d_i<br><br>\text{\hspace{1em}<br><br>}<br><br>\left(n\right)=\frac{1}{N}<br><br>\text{\hspace{1em}<br><br>}<br><br>\underset{k=0}{\overset{N-1}{\sum <br><br>}}<br><br>\text{\hspace{1em}<br><br>}<br><br>d_p<br><br>\text{\hspace{1em}<br><br>}<br><br>\left(t\right)<br><br>\text{\hspace{1em}<br><br>}<br><br>{\mathrm{<br><br>}}^{j<br><br>\text{\hspace{1em}<br><br>}<br><br>2<br><br>\text{\hspace{1em}<br><br>}<br><br>\mathrm{\pi <br><br>}<br><br>\text{\hspace{1em}<br><br>}<br><br>\mathrm{nk}/N},$

wherein n=1, 2, 3, . . . , and d_p(t) corresponding to said parallel converted data, and d_i(n) corresponding to said N modulated subcarriers outputted, and N being a predetermined positive number.

60. The method of claim 59, phases of said N subcarriers being orthogonal to each other.

61. The method of claim 50, said modulating further comprising:

receiving said first data, parallel converting said first data into a predetermined number of data items and outputting said parallel converted data;

generating said predetermined first frequency hopping code according to specified regulations when said parallel converted data are input to a first frequency hopping data storage unit, said parallel converted data corresponding to d_p(t);

outputting first frequency hopped data, said first frequency hopped data corresponding to said first frequency hopping code;

modulating said first frequency hopped data using frequencies of N predetermined subcarriers and outputting N modulated subcarriers on which said parallel converted data is loaded, said modulating corresponding to orthogonal-frequency-division-multiplexing modulating, said N modulated subcarriers outputted corresponding to d_i(n); and

receiving said N modulated subcarrier data, serially converting said received subcarrier data, and outputting said serially converted data.

62. The method of claim 61, said frequencies of said N predetermined subcarriers being determined to be different from each other in dependence upon said first frequency hopping code.

63. The method of claim 62, said first frequency hopping code being used by a first frequency hopping unit.

64. The method of claim 61, said modulating of said first frequency hopped data and said outputting of said N modulated subcarriers comprising:

obtaining said data d_i(n) by N-point complex inverse-fast-Fourier-transform converting said first data according to $d_i<br><br>\text{\hspace{1em}<br><br>}<br><br>\left(n\right)=\frac{1}{N}<br><br>\text{\hspace{1em}<br><br>}<br><br>\underset{k=0}{\overset{N-1}{\sum <br><br>}}<br><br>\text{\hspace{1em}<br><br>}<br><br>d_p<br><br>\text{\hspace{1em}<br><br>}<br><br>\left(t\right)<br><br>\text{\hspace{1em}<br><br>}<br><br>{\mathrm{<br><br>}}^{j<br><br>\text{\hspace{1em}<br><br>}<br><br>2<br><br>\text{\hspace{1em}<br><br>}<br><br>\mathrm{\pi <br><br>}<br><br>\text{\hspace{1em}<br><br>}<br><br>\mathrm{nk}/N},$

wherein n=1, 2, 3, . . . , and d_p(t) corresponding to said parallel converted data, and d_i(n) corresponding to said N modulated subcarriers outputted, and N being a predetermined positive number.