Apparatus and method for modulating data message by employing orthogonal variable spreading factor (OVSF) codes in mobile communication system

• US 7,443,906 B1
• Filed: 05/31/2000
• Issued: 10/28/2008
• Est. Priority Date: 05/31/1999
• Status: Expired due to Term

• Current Assignee: Electronics and Telecommunications Research Institute
• Original Assignee: Electronics and Telecommunications Research Institute
• Inventors: Shim, Jae-Ryong, Lee, Narm-Hee, Bang, Seung-Chan, Kim, Tae-Joong, Kim, Jae-Heung, Kim, Jung-Im, Chae, Jong-Suk, Lee, Hyuck-Jae
• Primary Examiner(s): BURD, KEVIN MICHAEL
• Application Number:
  US09/584,189
• Time in Patent Office: 3,072 Days
• Field of Search: 375/140, 375/146, 375/142, 375/144, 375/145, 375/130, 375/141, 375/147, 375/295
• US Class Current: 375/140
• CPC Class Codes: H04B 1/7073 Synchronisation aspects
• CPC Class Codes: H04B 2201/70703 using multiple or variable rates
• CPC Class Codes: H04J 13/0044 OVSF [orthogonal variable spreading factor]
• CPC Class Codes: H04J 13/10 Code generation
• CPC Class Codes: H04J 13/20 having an orthogonal variable spreading factor [OVSF]

Abstract

A method for converting source data to a channel-modulated signal having a plurality of pairs of in-phase (I) and quadrature-phase (Q) data in a mobile station, wherein the mobile station uses at least one channel, includes the steps of: a) encoding the source data to generate at least one data part and a control part; b) generating at least one spreading code to be allocated to the channel, wherein each spreading code is selected on the basis of a data rate of the data part and the control part and spreading codes are selected so that two consecutive pairs of the I and Q data are correspondent to two points located on same point or symmetrical with respect to a zero point on a phase domain; and c) spreading the control part and the data part by using the spreading code, to thereby generate the channel-modulated signal. The method is capable of improving a power efficiency of a mobile station by reducing a peak-to-average power ratio in a mobile communication system.

Claims

1. An apparatus for converting source data to a channel-modulated signal having a plurality of pairs of in-phase (I) and quadrature-phase (Q) data in a mobile station, wherein the mobile station uses (N−

1) data channels (N is an integer larger than two) and a control channel, the apparatus comprising;

channel coding means for encoding the source data to generate (N−

1) data parts and a control part, wherein the data parts are allocated to the data channels and the control part is allocated to the control channel;

code generating means for generating spreading codes to be allocated to the channels, wherein each of the spreading codes is selected on the basis of a data rate of the data part and the control part and spreading codes are selected so that two consecutive pairs of the I and Q data are correspondent to two points located on the same point or symmetrical with respect to a zero point on a phase domain; and

spreading means for spreading the control channel and the data channels by using the spreading codes to thereby generate the channel-modulated signal,

wherein;

the code generating means includes;

control means responsive to the spreading factor for generating code numbers for the channels; and

spreading code generation means responsive to the spreading factor and the code number for generating the spreading code to be allocated to the channels,

the spreading code generation means includes;

counting means for consecutively producing a count value in synchronization with a clock signal;

first spreading code generation means responsive to the count value and the spreading factor for generating the spreading codes to be allocated to the data channels; and

second spreading code generation means responsive to the count value and the spreading factor for generating the spreading code to he allocated to the control channel, the spreading codes correspond to an orthogonal variable spreading factor (OVSF) code, the spreading code allocated to the control channel is represented by C_256,0, where 256 denotes the spreading factor and 0 the code number,

the spreading codes allocated to first and second data channels are represented by C_{4, 1}={1, 1, −

1, −

1},

when there are more than two data channels, the spreading codes allocated to a third data channel and, when present, a fourth data channel are represented by C_{4, 3}={1, −

1, −

1, 1}, and

when there are more than four data channels, the spreading codes allocated to a fifth data channel and, when present, a sixth data channel are represented by C_{4, 2}={1, −

1, 1, −

1}.

2. The apparatus as recited in claim 1, wherein the first spreading code generation means includes:

first logical operation means responsive to the count value for carrying out a logical operation with the spreading factor and the code number related to a data part, to thereby generate the spreading code related to the data part; and

first selection means for outputting the spreading code related to the data part in response to a select signal as the spreading factor related to the data part.

3. The apparatus as recited in claim 2, wherein said first logical operation means receives a code number of I₇I₆I₅I₄I₃I₂I₁I₀, a count value of B₇B₆B₅B₄B₃B₂B₁B₀ and a predetermined spreading factor.

4. The apparatus as recited in claim 3, wherein the first logical operation means carries out a logical operation of

$\prod _{}^{}$

i = 0 N - 2 ⁢

⁢

I i ⊕

·

B N - 1 - i

if the predetermined spreading factor is 2^N where N is 2 to 8.

5. The apparatus as recited in claim 2, wherein said first logical operation means includes a plurality of AND gates and a plurality of exclusive OR gates.

6. The apparatus as recited in claim 2, wherein said first selection means includes a multiplexer.

7. The apparatus as recited in claim 1, wherein the second spreading code generation means includes:

second logical operation means responsive to the count value for carrying out a logical operation with the spreading factor and the code number related to the control part, to thereby generate the spreading code related to the control part; and

second selection means for outputting the spreading code related to the control part in response to a select signal as the spreading factor related to the control part.

8. The apparatus as recited in claim 7, wherein said second logical operation means receives a code number of I₇I₆I₅I₄I₃I₂I₁I₀, a count value of B₇B₆B₅B₄B₃B₂B₁B₀ and a predetermined spreading factor.

9. The apparatus as recited in claim 8, wherein the second logical operation means carries out a logical operation of

$\prod _{}^{}$

i = 0 N - 2 ⁢

⁢

I i ⊕

·

B N - 1 - i

if the predetermined spreading factor is 2^N where N is 2 to 8.

10. The apparatus as recited in claim 1, wherein said counting means includes an 8-bit counter when the 2^N is a maximum spreading factor.

67. The mobile station of claim 6, further comprising means for generating C_4,1, C_4,2, C_4,3, and C_256,0.

11. A method for converting source data to a channel-modulated signal having a plurality of pairs of in-phase (I) and quadrature-phase (Q) data in a mobile station, wherein the mobile station uses (N−

1) data channels (N is an integer larger than two) and a control channel, the method comprising the steps of;

a) encoding the source data to generate (N−

1) data parts and a control part, wherein the data parts are allocated to the data channels and the control part is allocated to the control channel;

b) generating spreading codes to be allocated to the channels, wherein each of the spreading codes is selected on the basis of a data rate of the data part and the control part and spreading codes are selected so that two consecutive pairs of the I and Q data are correspondent to two points located on the same point or symmetrical with respect to a zero point on a phase domain; and

c) spreading the control channel and the data channels by using the spreading codes to thereby generate the channel-modulated signal,

wherein;

step a) includes the steps of;

a1) encoding the source data to generate the data part and the control part; and

a2) generating a spreading factor related to the data rate of the data part,

step b) includes the steps of;

b1) generating code numbers for the channels in response to the spreading factor; and

b2) generating the spreading code to be allocated to the channels in response to the spreading factor and the code number,

step b2) includes the steps of;

b2-a) producing a count value in synchronization with a clock signal; and

b2-b) carrying out a logical operation with the spreading factor and the code number related to the data part and the control part in response to the count value, to thereby generate the spreading code related to the data part,

the spreading codes correspond to an orthogonal variable spreading factor (OVSF) code,

the spreading code allocated to the control channel is represented by C_256,0, where 256 denotes a spreading factor and 0 the code number,

the spreading codes allocated to first and second data channels are represented by C_{4, 1}={1, 1, −

1, −

1},

when there are more than two data channels, the spreading codes allocated to a third data channel and, when present, a fourth data channel are represented by C_{4, 3} ={1, −

1, −

1, 1}, and

when there are more than four data channels, the spreading codes allocated to a fifth data channel and, when present, a sixth data channel are represented by C_{4, 2}={1, −

1, 1, −

1}.

12. The method as recited in claim 11, wherein the code number and the count value are represented by an 8-bit signal of I₇I₆I₅I₄I₃I₂I₁I₀ and an 8-bit signal of B₇B₆B₅B₄B₃B₂B₁B₀, respectively.

13. The method as recited in claim 12, wherein the logical operation is accomplished by

$\prod _{}^{}$

i = 0 N - 2 ⁢

⁢

I i ⊕

·

B N - 1 - i

if the spreading factor is 2^N where N is 2 to 8.

14. An apparatus for converting source data to a channel-modulated signal having a plurality of pairs of in-phase (I) and quadrature-phase (Q) data in a mobile station, wherein the mobile station uses (N−

1) data channels (N is an integer larger than two) and a control channel, the apparatus comprising;

channel coding means for encoding the source data to generate (N−

1) data parts and a control part, wherein the data parts are allocated to the data channels and the control part is allocated to the control channel;

code generating means for generating spreading codes to be allocated to the channels, wherein each of the spreading codes is selected on the basis of a data rate of the data part and the control part and spreading codes are selected so that two consecutive pairs of the I and Q data are correspondent to two points located on the same point or symmetrical with respect to a zero point on a phase domain; and

spreading means for spreading the control channel and the data channels by using the spreading codes to thereby generate the channel-modulated signal,

wherein;

the spreading codes correspond to an orthogonal variable spreading factor (OVSF) code,

said channel coding means includes spreading factor generation means for generating a spreading factor related to the data rate of the data part,

the spreading code allocated to the control channel is represented by C_256,0, where 256 denotes the spreading factor and 0 the code number,

the spreading codes allocated to first and second data channels are represented by C_{4, 1}={1, 1, −

1, −

1},

said code generating means includes control means responsive to the spreading factor for generating code numbers for the channels, and spreading code generation means responsive to the spreading factor and the code number for generating the spreading code to be allocated to the channels, said spreading code generation means including, counting means for consecutively producing a count value in synchronization with a clock signal, first spreading code generation means responsive to the count value and the spreading factor for generating the spreading code to be allocated to the data channel, and second spreading code generation means responsive to the count value and the spreading factor for generating the spreading code to be allocated to the control channel, and

the second spreading code generation means includes;

second logical operation means responsive to the count value for carrying out a logical operation with the spreading factor and the code number related to the control part, to thereby generate the spreading code related to the control part; and

second selection means for outputting the spreading code related to the control part in response to a select signal as the spreading factor related to the control part.

15. The apparatus as recited in claim 14, wherein the first spreading code generation means includes:

first logical operation means responsive to the count value for carrying out a logical operation with the spreading factor and the code number related to the data part, to thereby generate the spreading code related to the data part; and

first selection means for outputting the spreading code related to the data part in response to a select signal as the spreading factor related to the data part,

and wherein said first logical operation means receives a code number of I₇I₆I₅I₄I₃I₂I₁I₀, a count value of B₇B₆B₅B₄B₃B₂B₁B₀ and a predetermined spreading factor.

16. The apparatus as recited in claim 15, wherein the first logical operation means carries out a logical operation of

$\prod _{}^{}$

i = 0 N - 2 ⁢

⁢

I i ⊕

·

B N - 1 - i

if the predetermined spreading factor is 2^N where N is 2 to 8.

17. The apparatus as recited in claim 14, wherein said second logical operation means receives a code number of I₇I₆I₅I₄I₃I₂I₁I₀, a count value of B₇B₆B₅B₄B₃B₂B₁B₀ and a predetermined spreading factor.

18. The apparatus as recited in claim 17, wherein the second logical operation means carries out a logical operation of

$\prod _{}^{}$

i = 0 N - 2 ⁢

⁢

I i ⊕

·

B N - 1 - i

if the predetermined spreading factor is 2^N where N is 2 to 8.

19. A method for converting source data to a channel-modulated signal having a plurality of pairs of in-phase (I) and quadrature-phase (Q) data in a mobile station, wherein the mobile station uses (N−

1) data channels (N is an integer larger than two) and a control channel, the method comprising the steps of;

a) encoding the source data to generate (N−

1) parts and a control part, wherein the data part are allocated to the data channel and the control part is allocated to the control channel;

b) generating spreading codes to be allocated to the channels, wherein each of the spreading codes is selected on the basis of a data rate of the data part and the control part and spreading codes are selected so that two consecutive pairs of the I and Q data are correspondent to two points located on the same point or symmetrical with respect to a zero point on a phase domain; and

c) spreading the control channel and the data channels by using the spreading codes to thereby generate the channel-modulated signal,

wherein the spreading code is an orthogonal variable spreading factor (OVSF) code and the spreading code allocated to the control channel is represented by C_256,0, where 256 denotes spreading factor and 0 code number,

the spreading codes allocated to first and second data channels are represented by C_{4, 1}={1, 1, −

1, −

1}, and

said step a) includes;

a1) encoding the source data to generate the data part and the control part; and

a2) generating a spreading factor related to the data said step b) including,

b1) generating code numbers for the channels in response to the spreading factor; and

b2) generating the spreading code to be allocated to the channels in response to the spreading factor and the code number, said step b2) further including;

b2-a) producing a count value in synchronization with a clock signal; and

b2-b) carrying out a logical operation with the spreading factor and the code number related to the data parts and the control part in response to the count value to thereby generate the spreading code related to the data part.

20. The method as recited in claim 19, wherein the code number and the count value are represented by an 8-bit signal of I₇I₆I₅I₄I₃I₂I₁I₀ and an 8-bit signal of B₇B₆B₅B₄B₃B₂B₁B₀, respectively.

21. The method as recited in claim 20, wherein the logical operation is accomplished by

$\prod _{}^{}$

i = 0 N - 2 ⁢

⁢

I i ⊕

·

B N - 1 - i

if the spreading factor is 2^N where N is 2 to 8.

22. A spreading method for a mobile station, wherein the mobile station is capable of using at least three data channels and at least one control channel, comprising:

systematically spreading a first one of the data channels by C_4,1;

systematically spreading a second one of the data channels by C_4,1; and

systematically spreading a third one of the data channels by C_4,3, wherein

C_4,1 is a first orthogonal variable spreading factor code with the spreading factor of 4 and the code number of 1,

C_4,3 is a second orthogonal variable spreading factor code with the spreading factor of 4 and the code number of 3, and

when three and not more than three of the data channels are used, the first one of the data channels, the second one of the data channels, and the third one of the data channels are used.

23. The method of claim 22, wherein C_4,1 represents {1, 1, −

1, −

1} and C_4,3 represents {1, 1, −

1, −

1}.

24. The method of claim 23, further comprising:

spreading the at least one control channel by C_256,0, wherein C_256,0 is a third orthogonal variable spreading factor code with the spreading factor of 256 and the code number of 0.

25. The method of claim 24, wherein

the mobile station uses the data channels such that at least the first one of the data channels and the third one of the data channels are coupled to an in-phase branch, and

the mobile station uses the data channels and the at least one control channel such that at least the second one of the data channels and the at least one control channel are coupled to a quadrature-phase branch.

26. The method of claim 24, further comprising:

allocating the first one of the data channels and the third one of the data channels to an in-phase branch, and

allocating the at least one control channel and the second one of the data channels to a quadrature-phase branch.

27. The method of claim 24, further comprising:

generating C_4,1, C_4,3, and C_4,2.

28. The method of claim 22, further comprising:

when more than three of the data channels are used, systematically spreading a fourth one of the data channels by C_4,3, wherein

when four and not more than four of the data channels are used, the first one of the data channels, the second one of the data channels, the third one of the data channels, and the fourth one of the data channels are used.

29. The method of claim 28, further comprising:

spreading the at least one control channel by C_256,0 is a third orthogonal variable spreading factor code with the spreading factor of 256 and the code number of 0.

30. The method of claim 29, wherein

the mobile station uses the data channels such that at least the first one of the data channels and the third one of the data channels are coupled to an in-phase branch, and

the mobile station uses the data channels and the at least one control channel such that at least the second one of the data channels and the fourth one of the data channels and the at least one control channel are coupled to a quadrature-phase branch.

31. The method of claim 29, further comprising:

allocating the first one of the data channels and the third one of the data channels to an in-phase branch; and

allocating the second one of the data channels and the fourth one of the data channels and the at least one control channel to a quadrature-phase branch.

32. The method of claim 28, further comprising:

when more than four of the data channels, systematically spreading a fifth one of the data channels by C_4,2; and

when more than five of the data channels are used, systematically spreading a sixth one of the data channels by C_4,2, wherein

C_4,2 is a fourth orthogonal variable spreading factor code with the spreading factor of 4 and the code number of 2,

when five and not more than five of the data channels are used, the first one of the data channels, the second one of the data channels, the third one of the data channels, the fourth one of the data channels, and the fifth one of the data channels are used, and

when six of the data channels are used, the first one of the data channels, the second one of the data channels, the third one of the data channels, the fourth one of the data channels, the fifth one of the data channels, and the sixth one of the data channels are used.

33. The method of claim 32, wherein

C_4,1 represents {1, 1, −

1, −

1}, C_4,2 represent {1, −

1, 1, −

1}, and C_4,3 represents {1, −

1, −

1, 1}.

34. The method of claim 33, further comprising:

spreading the at least one control channel by C_{256, 0}, wherein C_256,0 is a third orthogonal variable spreading factor code with the spreading factor of 256 and the code number of 0.

35. The method of claim 34, wherein

the mobile station uses the data channels such that at least the first one of the data channels and the third one of the data channels are coupled to an in-phase branch;

the mobile station uses data channels and the at least one control channel such that at least the second one of the data channels and the at least one control channel are coupled to a quadrature-phase branch.

36. The method of claim 35, wherein

the mobile station uses the data channels such that the fourth one of the data channels is coupled to the quadrature-phase branch.

37. The method of claim 36, wherein

the mobile station uses the data channels such that the fifth one of the data channels is coupled to the in-phase branch, and

the mobile station uses the data channels such that the sixth one of the data channels is coupled to the quadrature-phase branch.

38. The method of claim 34, further comprising:

allocating the first one of the data channels and the third one of the data channels to an in-phase branch; and

allocating the at least one control channel and the second one of the data channels to a quadrature-phase branch.

39. The method of claim 38, further comprising:

allocating the fourth one of the data channels to the quadrature-phase branch.

40. The method of claim 39, further comprising:

allocating the fifth one of the data channels to the in-phase branch, and

allocating the sixth one of the data channels to the quadrature-phase branch.

41. The method of claim 34, further comprising:

generating C_4,1, C_4,3, and C_4,2.

42. The method of claim 22 where the third one of the data channels is systematically spread with C_4,3 instead of C_4,2 to reduce the peak to average power ratio of the mobile station.

43. A spreading method for a mobile station, wherein the mobile station is capable of using at least three data channels and at least one control channel, comprising:

receiving first data on a first one of the data channels;

receiving second data on a second one of the data channels;

receiving third data on a third one of the data channels;

systematically spreading the first data by C_4,1;

systematically spreading the second data by C_4,1; and

systematically spreading the third data with C_4,3, wherein

when three and not more than three of the data channels are used, the first and second one of the data channels and the third one of the data channels are used, and

C_I,K represents an orthogonal variable spreading factor code, with I being a spreading factor and K being a code number, wherein 0≦

K<

I.

44. The method of claim 43, wherein

C_4,1 represents {1, 1, −

1, −

1} and C_4,3 represents {1, −

1, −

1, 1}.

45. The method of claim 44, further comprising:

allocating C_256,0 to the at least one control channel.

46. The method of claim 45, wherein

the mobile station uses the data channels such that at least the first one of the data channels and the third one of the data channels are coupled to an in-phase branch, and

the mobile station uses data channels and the at least one control channel such that at least the at least one control channel and the second one of the data channels are coupled to a quadrature-phase branch.

47. The method of claim 45, further comprising:

allocating the first one of the data channels and the third one of the data channels to an in-phase branch, and

allocating the at least one control channel and the second one of the data channels to a quadrature-phase branch.

48. The method of claim 45, further comprising:

generating C_4,1 and C_4,3.

49. The method of claim 43, further comprising:

receiving fourth data on a fourth one of the data channels; and

systematically spreading the fourth data by C_4,3;

wherein

the mobile station uses the data channels such that when the mobile station uses four and not more than four of the data channels, the first one of the data channels, the second one of the data channels, the third one of the data channels, and the fourth one of the data channels are used.

50. The method of claim 49, further comprising:

allocating C_256,0 to the at least one control channel.

51. The method of claim 50, wherein

the mobile station uses the data channels such that at least the first one of the data channels and the third one of the data channels are coupled to an in-phase branch, and

the mobile station uses data channels and the at least one control channel such that at least the second one of the data channels, the fourth one of the data channels, and the at least one control channel are coupled to a quadrature-phase branch.

52. The method of claim 50, further comprising:

allocating the first one of the data channels and the third one of the data channels to an in-phase branch; and

allocating the second one of the data channels and the fourth one of the data channels and the at least one control channel to a quadrature-phase branch.

53. The method of claim 49, further comprising:

receiving fifth data on a fifth one of the data channels;

systematically spreading the fifth data with C_4,2;

receiving sixth data on a sixth one of the data channels; and

systematically spreading the sixth data with C_4,2, wherein

when five and not more than five of the data channels are used, the first one of the data channels, the second one of the data channels, the third one of the data channels, the fourth one of the data channels, and the fifth one of the data channels are used, and

when six of the data channels used, the first one of the data channels, the second one of the data channels, the third one of the data channels, the fourth one of the data channels, the fifth one of the data channels, and the sixth one of the data channels are used.

54. The method of claim 53, wherein

C_4,1 represents {1, 1, −

1, −

1}, C_4,2 represents {1, −

1, −

1, 1}.

55. The method of claim 54, further comprising:

allocating C_{256, 0} to the at least one control channel.

56. The method of claim 55, wherein

the mobile station uses the data channels such that at least the first one of the data channels and the third one of the data channels are coupled to an in-phase branch;

the mobile station uses the data channels and the at least one control channel such that at least the second one of the data channels and the at least one control channel are coupled to a quadrature-phase branch.

57. The method of claim 54, wherein

the mobile station uses the data channels such that the fourth one of the data channels is coupled to the quadrature-phase branch.

58. The method of claim 57, wherein

the mobile station uses the data channels such that the fifth one of the data channels is coupled to the in-phase branch, and

the mobile station uses the data channels such that the sixth one of the data channels is coupled to the quadrature-phase branch.

59. The method of claim 55, further comprising:

allocating the first one of the data channels and the third one of the data channels to an in-phase branch; and

allocating the at least one control channel and the second one of the data channels to a quadrature-phase branch.

60. The method of claim 59, further comprising:

allocating the fourth one of the data channels to the quadrature-phase branch.

61. The method of claim 60, further comprising:

allocating the fifth one of the data channels to the in-phase branch, and

allocating the sixth one of the data channels to the quadrature-phase branch.

62. The method of claim 55, further comprising:

generating C_4,1, C_4,3, and C_4,2.

63. The method of claim 43 where the third data is systematically spread with C_4,3 instead of C_4,2 to reduce the peak to average power ratio of the mobile station.

64. The method of claim 43 where the third one of the data channels is systematically spread with C_4,3 instead of C_4,2 to reduce the peak to average power ratio of the mobile station.

65. A mobile station, wherein the mobile station is configured to use a plurality of data channels at least one control channel, comprising:

means for receiving data on the data channels,

wherein a first one of the data channels, a second one of the data channels, and a third one of the data channels are configured to be used when three and not more than three of the data channels are configured to be used,

the first one of the data channels, the second one of the data channels, the third one of the data channels, and a fourth one of the data channels are configured to be used when four and not more than four of the data channels are configured to be used,

the first one of the data channels, the second one of the data channels, the third one of the data channels, the fourth one of the data channels, and a fifth one of the data channels are configured to be used when five and not more than five of the data channels are configured to be used, and

the first one of the data channels, the second one of the data channels, the third one of the data channels, the fourth one of the data channels, the fifth one of the data channels, and a sixth one of the data channels are configured to be used when six of the data channels are configured to be used; and

means for spreading systematically the first one of the data channels by C_4,1, the second one of the data channel by C_4,1, the third one of the data channels by C_4,3, the fourth one of the data channels by C_4,3, the fifth one of the data channels by C_4,2, the sixth one of the data channels by C_4,2, and the at least one control channel by C_256,0, respectively, wherein C_I,K represents an orthogonal variable spreading factor code, with I being a spreading factor and K being a code number, wherein 0≦

K21 I.

66. The mobile station of claim 65, wherein

C_4,1 represents {1, 1, −

1, −

1}, C_4,2 represents {1, −

1, 1, −

1}, and C_4,3 represents {1, −

1, −

1, 1}.

68. The mobile station of claim 65 wherein the third one of the data channels is systematically spread with C_4,3 instead of C_4,2 to reduce the peak to average power ratio of the mobile station.

69. An apparatus for a mobile communication system, wherein the apparatus is configured to use a plurality of data channels at least one control channel, comprising:

a first spreading unit configured to spread systematically a first one of the data channels by C_4,1;

a second spreading unit configured to spread systematically a second one of the data channels by C_4,1; and

a third spreading unit configured to spread systematically a third one of the data channels by C_4,3;

wherein

C_4,1 is a first orthogonal variable spreading factor code with the spreading factor of 4 and the code number of 1,

C_4,3 is a second orthogonal variable spreading factor code with the spreading factor of 4 and the code number of 3, and

the first one of the data channels, the second one of the data channels, and the third one of the data channels are configured to be used when three and not more than three of the data channels are configured to be used.

70. The apparatus of claim 69, further comprising:

a fourth spreading unit configured to spread the at least one control channel by C_256,0;

wherein

C_256,0 is a third orthogonal variable spreading factor code with the spreading factor of 256 and the code number of 0.

71. The apparatus of claim 69, further comprising

an in-phase branch and a quadrature-phase branch, wherein

at least the first one of the data channels and the third one of the data channels are coupled to the in-phase branch, and

at least the second one of the data channels and the at least one control channel are coupled to the quadrature-phase branch.

72. The apparatus of claim 71, further comprising:

a fifth spreading unit configured to spread systematically a fourth one of the data channels by C_4,3, wherein

the first one of the data channels, the second one of the data channels, the third one of the data channels, and the fourth one of the data channels are configured to be used when four and not more than four of the data channels are used, and

the fourth one of the data channels is coupled to the quadrature-phase branch.

73. The apparatus of claim 72, further comprising:

a sixth spreading unit configured to spread systematically a fifth one of the data channels by C_4,2; and

a seventh spreading unit configured to spread systematically a sixth one of the data channels by C_4,2, wherein C_4,2 is a first orthogonal variable spreading factor code with the spreading factor of 4 and the code number of 2,

the first one of the data channels, the second one of the data channels, the third one of the data channels, the fourth one of the data channels, and the fifth one of the data channels are configured to be used when five and not more than five of the data channels are configured to be used,

the first one of the data channels, the second one of the data channels, the third one of the data channels, the fourth one of the data channels, the fifth one of the data channels, and the sixth one of the data channels are configured to be used when six of the data channels are configured to be used,

the fifth one of the data channels is coupled to the in-phase branch, and

the sixth one of the data channels is coupled to the quadrature-phase branch.

74. The mobile station of claim 73, further comprising:

a spreading code generation unit configured to generate C_4,1, C_4,2, C_4,3, and C_256,0.

75. The apparatus of claim 69 where the third one of the data channels data is systematically spread with C_4,3 instead of C_4,2 to reduce the peak to average power ratio of the mobile station.

76. A mobile station, wherein the mobile station is configured to use a plurality of data channels and at least one control channel, comprising:

an allocation unit configured to allocate first data to a first one of the data channels, second data to a second one of the data channels, third data to a third one of the data channels, fourth data to a fourth one of the data channels, fifth data to a fifth one of the data channels, and sixth data to a sixth one of the data channels, and control data to the at least one control channel, respectively;

a first multiplier configured to multiply systematically the first data by C_4,1;

a second multiplier configured to multiply systematically the second data by C_4,1;

a third multiplier configured to multiply systematically the third data by C_{4, 3};

a fourth multiplier configured to multiply systematically the fourth data by C_{4, 3};

a fifth multiplier configured to multiply systematically the fifth data by C_4,2;

a sixth multiplier configured to multiply systematically the sixth data by C_4,2; and

a seventh multiplier configured to multiply the control data by C_256,0, wherein

the first one of the data channels and the second one of the data channels are configured to be used when two and not more than two of the data channels are used,

the first one of the data channels, the second one of the data channels, and the third one of the data channels are configured to be used when three and not more than three of the data channels are configured to be used,

the first one of the data channels, the second one of the data channels, the third one of the data channels, and the fourth one of the data channels are configured to be used when four and not more than four of the data channels are used,

the first one of the data channels, the second one of the data channels, the third one of the data channels, the fourth one of the data channels, and the fifth one of the data channels are configured to be used when five and not more than five of the data channels are configured to be used, and

the first one of the data channels, the second one of the data channels, the third one of the data channels, the fourth one of the data channels, the fifth one of the data channels, and the sixth one of the data channels are configured to be used when six of the data channels are configured to be used, and

C_I,K represents an orthogonal variable spreading factor code, I being a spreading factor and K being a code number, wherein 0≦

K<

I.

77. The mobile station of claim 76, further comprising:

an in-phase branch and a quadrature-phase branch, wherein

at least the first one of the data channels, the third one of the data channels, and the fifth one of the data channels are coupled to the in-phase branch, and

at least the at least one control channel and the second one of the data channels, the fourth one of the data channels, and the sixth one of the data channels are coupled to the quadrature-phase branch.

78. The mobile station of claim 77, further comprising:

a spreading code generation unit configured to generate C_4,1, C_4,2, C_4,3, and C_256,0.

79. The mobile station of claim 76, wherein C_4,1 represents {1, 1, −

1, −

1}, C_4,2 represents {1, −

1, 1, −

1}, and C_4,3 represents {1, −

1, −

1, 1}.

80. The mobile station of claim 76 wherein the third multiplier systematically multiplies the third data by C_4,3 instead of C_4,2 to reduce the peak to average power ratio of the mobile station.

81. An apparatus for a mobile communication system, wherein the apparatus is configured to use a plurality of data channels and at least one control channel, comprising:

an allocation unit configured to allocate first data to a first one of the data channels, second data to a second one of the data channels, and third data to a third one of the data channels; and

a multiplying unit configured to multiply systematically the first data by C_4,1, the second data by C_4,1, and the third data by C_4,3, wherein

the first one of the data channels, the second one of the data channels, and the third one of the data channels are configured to be used when three and not more than three of the data channels are used, and

C_I,K represents an orthogonal variable spreading factor code, I being a spreading factor and K being a code number, wherein 0≦

K<

I.

82. The apparatus of claim 81, further comprising:

an in-phase branch and a quadrature-phase branch, wherein

at least the first one of the data channels and the third one of the data channels are coupled to the in-phase branch, and

at least the second one of the data channels is coupled to the quadrature-phase branch.

83. The apparatus of claim 81, wherein

the allocation unit is further configured to allocate control data to the at least one control channel, and

the spreading unit is further configured to spread the control data by C_256,0.

84. The apparatus of claim 83, further comprising:

an in-phase branch and a quadrature-phase branch, wherein

at least the first one of the data channels and the third one of the data channels are coupled to the in-phase branch, and

at least one control channel and the second one of the data channels are coupled to the quadrature-phase branch, wherein

the apparatus is configured to use the data channels such that the data channels are spread by one or more orthogonal variable spreading factor codes.

85. The apparatus of claim 81 where the third data is multiplied by C_4,3 instead of C_4,2 to reduce the peak to average power ratio of the mobile station.

86. A mobile station, wherein the mobile station is configured to spread at least one or more data channels by one or more orthogonal variable spreading factor codes, comprising:

a spreading unit configured to spread systematically a first one of the data channels and a second one of the data channels by C_4,1, and to spread systematically a third one of the data channels by C_4,3, wherein

the first one of the data channels, the second one of the data channels, and the third one of the data channels are configured to be spread by the one or more orthogonal variable spreading factor codes when three and not more than three of the data channels are configured to be spread by one or more orthogonal variable spreading factor codes, and

C_I,K represents one of the orthogonal variable spreading factor codes, I being a spreading factor and K being a code number, wherein 0≦

K<

I.

87. The mobile station of claim 86, further comprising:

an in-phase branch, at least the first one of the data channels and the third one of the data channels being coupled to the in-phase branch, and

a quadrature-phase branch, at least the second one of the data channels being coupled to the quadrature-phase branch.

88. The mobile station of claim 87, wherein

the spreading unit is further configured to spread a control channel, the control channel being coupled to the quadrature-phase branch.

89. The mobile station of claim 86 wherein the third one of the data channels is systematically spread by C_4,3 instead of C_4,2 to reduce the peak to average power ratio of the mobile station.

90. A mobile station, wherein the mobile station is configured to use at least one or more data channels, comprising:

a first spreading unit configured to spread systematically at least a first one of the data channels by C_4,1 and a third one of the data channels by C_4,3; and

a second spreading unit configured to spread systematically at least a second one of the data channels by C₄, wherein

the first one of the data channels, the second one of the data channels, and the third one of the data channels are configured to be used when three and not more than three of the data channels are configured to be used, and

C_I,K represents an orthogonal variable spreading factor code, I being a spreading factor and K being a code number, wherein 0≦

K<

I.

91. The mobile station of claim 90, further comprising:

an in-phase branch, at least the first one of the data channels and the third one of the data channels being coupled to the in-phase branch, and

a quadrature-phase branch, at least the second one of the data channels being coupled to the quadrature-phase branch.

92. The mobile station of claim 91, wherein

the second spreading unit is further configured to spread a control channel, the control channel being coupled to the quadrature-phase branch, and

the mobile station is configured to use the data channels such that the data channels are spread by the one or more orthogonal variable spreading factor codes.

93. The mobile station of claim 90 wherein the third one of the data channels is systematically spread by C_4,3 instead of C_4,2 to reduce the peak to average power ratio of the mobile station.

95. The method of claim 93, wherein C_4,1 represents {1, 1, −

1, −

1} and C_4,3 represents {1, −

1, −

1, 1}.

94. A method for a mobile station, wherein the mobile station is capable of transmitting at least three data channels and at least one control channel, comprising:

systematically spreading a first one of the data channels by C_4,1;

systematically spreading a second one of the data channels by C_4,1; and

systematically spreading a third one of the data channels by C_4,3;

wherein

when the mobile station transmits three and not more than three of the data channels, the first one of the data channels, the second one of the data channels, and the third one of the data channels are transmitted, and

C_I,K represents an orthogonal variable spreading factor code, with I being a spreading factor and K being a code number, wherein 0≦

K<

I.

96. The method of claim 94, further comprising:

spreading the at least one control channel by C_256,0.

97. The method of claim 96, wherein

at least the first one of the data channels and the third one of the data channels are coupled to an in-phase branch, and

at least the at least one control channel and the second one of the data channels are coupled to a quadrature-phase branch.

98. The method of claim 96, further comprising:

assigning the first one of the data channels and the third one of the data channels to an in-phase branch; and

assigning the at least one control channel and the second one of the data channels to a quadrature-phase branch.