Apparatus and method for allocating channel using OVSF code for uplink synchronous transmission scheme in a W-CDMA communication system

1. A channel allocation method in a CDMA (Code Division Multiple Access) communication system, comprising the steps of:

receiving from a UTRAN (UMTS (Universal Mobile Terrestrial System) Terrestrial Radio Access Network) one SF (Spreading Factor) node C SF,k out of 2 m− 1 SF nodes (where m is an integer larger than 3) arranged in the form of a tree having a mother node and child nodes;

searching a group including the received SF node C SF,k in accordance with

For

⁢

⁢

SF

≤

2

m

-

1

4

,

(

P

1

·

SF

,

P

1

·

k

)

=

(

2

m

-

1

4

,

n

)

For

⁢

⁢

SF

>

2

m

-

1

4

,

(

P

2

·

2

m

-

1

4

,

P

2

·

n

)

=

(

SF

,

k

)

where

,

P

1

=

2

m

-

1

4

·

SF

⁢

⁢

and

⁢

⁢

P

2

=

4

·

SF

2

m

-

1

;

spreading a signal on a dedicated physical data channel (DPDCH) with an OVSF (Orthogonal Variable Spreading Factor) code corresponding to a selected one of the received SF node and its child nodes in the searched group; and

spreading a signal on a dedicated physical control channel (DPCCH) with an OVSF code corresponding to an SF node determined by

F

⁡

(

C

2

m

-

1

4

·

k

)

=

C

2

m

-

1

,

2

m

-

1

-

k

-

1

⁢

⁢

(

k

=

0

,

1

,

…

⁢

)

if the n of the received SF node is the first half value having (2 m −1)/4 and

F

⁡

(

C

2

m

-

1

4

·

k

)

=

C

2

m

-

1

,

2

m

-

1

-

(

k

-

32

)

⁢

⁢

(

k

=

0

,

1

,

…

⁢

)

if the n thereof is the latter half value halving the same.

2. The channel allocation method as claimed in claim 1 , wherein if a spreading factor in the SF node C SF,k is SF=64 and an associated spreading factor for a control part is SF=256, a spreading factor C control,256,127− of the DPCCH is mapped to a spreading factor C data,64,k of the DPDCH, and a spreading factor C control,256,255−k of the DPCCH is mapped to a spreading factor C data,64,32+k of the DPDCH in accordance with:

F ( C data,64,k )= C control,256,127−k

F ( C data,64,32+k )= C control,256,255−k

where k=0, 1, 2, 3, . . . , 23.

3. The channel allocation method as claimed in claim 1 , wherein if a spreading factor in the SF node C SF,k is SF=64 and an associated spreading factor for a control part is SF=256, a spreading factor C control,256,96+k of the DPCCH is mapped to a spreading factor C data,64,k of the DPDCH, and a spreading factor C control,256,224+k of the DPCCH is mapped to a spreading factor C data,64,32+k of the DPDCH in accordance with:

  F ( C data,64,k )= C control,256,96+k

F ( C data,64,32 +k )= C control,256,224+k

where k=0, 1, 2, 3 , . . . , 23.

4. The channel allocation method as claimed in claim 1 , wherein in the case where a spreading factor in the SF node C SF,k is SF=1 28 and an associated spreading factor for a control part is SF=256, when k in a spreading factor C data,128,k of the DPDCH is an even number, a spreading factor of the DPCCH is mapped according to F(C data,128,k )=C control,256,127−k ; when the k is an odd number, the spreading factor of theDPCCH is mapped according to F 7 (C data,128,2n+1 )=F 7 (C data,128,2(n+8)+1 )=F 7 (C data,128,2(n+16)+1 )=C control,256,103−n , (for 0≦n≦7); when k in a spreading factor C data,64,32+k of the DPDCH is an even number, the spreading factor of the DPCCH is mapped according to F(C data,128,64+k )=C control,256,255−k ; and when the k is an odd number, the spreading factor of the DPCCH is mapped according to

F 7 ( C data,128,64,+2n+1 )= F 7 ( C data,128,64+2(n+8)+1 )= F 7 ( C data,128,64+2(n+16)+1 )= C control,256,207−n , (for 0≦n≦7), where k= 0, 1, 2, 3, . . . , 23.

5. An uplink channel transmission apparatus for a user equipment (UE) in a CDMA communication system, comprising:

a memory for storing 2 m−1 SF nodes (where m is an integer larger than 3) arranged in the form of a tree having a mother node and child nodes;

an input unit for receiving one SF node C SF,k from a UTRAN;

an OVSF code allocating device for searching a group including the received SF node C SF,k according to

For

⁢

⁢

SF

≤

2

m

-

1

4

,

(

P

1

·

SF

,

P

1

·

k

)

=

(

2

m

-

1

4

,

n

)

2

m

-

1

4

⁢

⁢

For

⁢

⁢

SF

>

2

m

-

1

4

,

(

P

2

·

2

m

-

1

4

,

P

2

·

n

)

=

(

SF

,

k

)

where

,

P

1

=

2

m

-

1

4

·

SF

⁢

⁢

and

⁢

⁢

P

2

=

4

·

SF

2

m

-

1

,

selecting one node for a data part out of the receivedSF node and associated child nodes from the searched group, and selecting an SF node for a control part determined by

F

⁡

(

C

2

m

-

1

4

·

k

)

=

C

2

m

-

1

,

2

m

-

1

-

k

-

1

⁢

⁢

(

k

=

0

,

1

,

…

⁢

)

if the n of the received SF node is the first half value halving (2 m −1)/4 and

F

⁡

(

C

2

m

-

1

4

·

k

)

=

C

2

m

-

1

,

2

m

-

1

-

(

k

-

32

)

⁢

⁢

(

k

=

0

,

1

,

…

⁢

)

if the n thereof is the latter half value halving the same;

an OVSF code generator for generating OVSF codes for a DPDHC and a DPCCH corresponding to the selected SF nodes of the data part and the control part;

a DPDCH spreader for spreading a signal on the DPDCH with the generated OVSF code for the data part; and

a DPCCH spreader for spreading a signal on the DPCCH with the generated OVSF code for the control part.

6. The uplink channel transmission apparatus as claimed in claim 5 , wherein if a spreading factor in the SF node C SF,k is SF=64 and an associated spreading factor for the control part is SF=256, a spreading factor C control,256,255−k of the DPCCH is mapped to a spreading factor C data,64,k of the DPDCH, and a spreading factor C control,256,255−k of the DPCCH is mapped to a spreading factor C data,64,32+k of the DPDCH in accordance with:

F ( C data,64,k )= C control,256,127−k

F ( C data,64,32+k )= C control,256,255−k

where k=0, 1, 2, 3, . . . , 23.

7. The uplink channel transmission apparatus as claimed in claim 5 , wherein in the case where a spreading factor in the SF node C SF,k is SF=128 and an associated spreading factor for the control part is SF=256, when k in a spr ading factor C data,128,k of the DPDCH is an even number, a spreading factor of the DPCCH is apped according to F(C data,128,k )=C control,256,127−k ; when k is an odd number, the spreading factor of the DPCCH is mapped according to F 7 (C data,128,2n+1 )=F 7 (C data,128,2(n+8)+1 )=F 7 (C data,128,2(n+16)+1 )=C control,256,103−n , (for 0≦n≦7); when k in the spreading factor C data,64,32+k of the DPDCH is an even number, the spreading factor of the DPCCH is mapped according to F(C data,128,64+k )=C control,256,255−k ; and when k is an odd number, the spreading factor of the DPCCH is mapped according to

F 7 ( C data,128,64+2n+1 )= F 7 ( C data,128,64+2(n+8)+1 )= F 7 ( C data,128,64+2(n+16)+1 )= C control,256,207−n , (for 0≦n≦7), where k= 0, 1, 2, 3,. . . , 23.

8. An uplink channel transmission apparatus for a UTRAN in a CDMA communication system, comprising:

a memory for storing 2 m−1 SF nodes (where m is an integer larger than 3) arranged in the form of a tree having a mother node and child nodes;

an input unit for receiving one SF node C SF,k from a UE;

an OVSF code allocating device for searching a group including the received SF node C SF,k according to

For

⁢

⁢

SF

≤

2

m

-

1

4

,

(

P

1

·

SF

,

P

1

·

k

)

=

(

2

m

-

1

4

,

n

)

For

⁢

⁢

SF

>

2

m

-

1

4

,

(

P

2

·

2

m

-

1

4

,

P

2

·

n

)

=

(

SF

,

k

)

where

,

P

1

=

2

m

-

1

4

·

SF

⁢

⁢

and

⁢

⁢

P

2

=

4

·

SF

2

m

-

1

,

selecting one node for a data part out of the received SF node and associated child nodes from the searched group, and selecting an SF node for a control part determined by

F

⁡

(

C

2

m

-

1

4

·

k

)

=

C

2

m

-

1

,

2

m

-

1

-

k

-

1

⁢

⁢

(

k

=

0

,

1

,

…

⁢

)

if the n of the received SF node is the first half value halving (2 m −1)/4 and

F

⁡

(

C

2

m

-

1

4

·

k

)

=

C

2

m

-

1

,

2

m

-

1

-

(

k

-

32

)

⁢

⁢

(

k

=

0

,

1

,

…

⁢

)

if the n thereof is the latter half value halving the same;

an OVSF code generator for generating OVSF codes for a DPDCH and a DPCCH corresponding to the selected SF nodes of the data part and the control part;

a DPDCH despreader for despreading a signal on the DPDCH with the generated OVSF code for the data part; and

a DPCCH despreader for despreading a signal on the DPCCH with the generated OVSF code for the control part.

9. A method for assigning a first OVSF code and a second OVSF code which respectively spread data signals and control signals, in a mobile communication system having an OVSF code wherein 2 m −1 SF nodes are arranged in the form of a tree in m+1 column and the SF nodes are divided into a pair of trees having first and second half SF nodes obtained by halving first SF nodes in a column corresponding to a maximum SF, the method comprising the steps of:

each tree allocating an OVSF code corresponding to one of some SF nodes in anm+1 column which becomes child nodes of one node out of second SF nodes following the first SF nodes as the first OVSF code for spreading a control signal; and

allocating the second OVSF code corresponding to one of the remaining nodes which maintain orthogonality with said one of the second SF nodes to spread a data signal;

wherein the maximum SF node is C 4,k (where k=0, 1, 2, 3), the first SF nodes include C 4,0 and C 4,2 , the second SF nodes incJude C 4,1 and C 4,3 , the second SF node C 4,1 includes child nodes C 8,2 and C 8,3 , the second SF node C 4,3 includes child nodes C 8,6 and C 8,7 , the child nodes C 8,3 and C 8,7 are allocated as the second OVSF code for spreading the control signal, and the remaining nodes are allocated as the first OVSF code for spreading the data signal; and

wherein the first OVSF codes for spreading the data signal and the second OVSF codes for spreading the control signal are so allocated as to be mapped according to:

F ( C data,64,k )= C control,256,127−k

F ( C data,64,32+k )= C control,256,255−k ,

where a spreading factor of the data signal is SF=64, a spreading factor of the control signal is SF=256, and k=0, 1, 2, 3, . . . , 23.

10. A method for assigning a first OVSF (Orthogonal Variable Spreading Factor) code and a second OVSF code which respectively spread data signals and control signals, in a mobile communication system having an OVSF code wherein 2 m −1 SF (Spreading Factor) nodes are arranged in the form of a tree in m+1 column and the SF nodes are divided into a pair of trees having first and second half SF nodes obtained by halving first SF nodes in a column corresponding to a maximum SF, the method comprising the steps of:

each tree allocating an OVSF code corresponding to one of some SF nodes in an m+1 th column which becomes child nodes of one node out of second SF nodes following the first SF nodes as the first OVSF code for spreading a control signal; and

allocating the second OVSF code corresponding to one of the remaining nodes which maintain orthogonality with said one of the second SF nodes to spread a data signal;

wherein the maximum SF node is C 4,k (where k=0, 1, 2, 3), the first SF nodes include C 4,0 and C 4,2 , the second SF nodes include C 4,i , and C 4,3 , the second SF node C 4,1 includes child nodes C 8,2 and C 8,3 , the second SF node C 4,3 includes child nodes C 8,6 and C 8,7 , the child nodes C 8,3 and C 8,7 , are allocated as the second OVSF code for spreading the control signal, and the remaining nodes are allocated as the first OVSF code for spreading the data signal; and

wherein when k is an even number, the first OVSF codes for spreading the data signal and the second OVSF codes for spreading the control signal are mapped according to F(C data,128,k )=C control,256,127−k and F(C data,128,64+k )=C control,256,255−k ,and when k is an odd number, the first OVSF codes and the second OVSF codes are mapped according to F 7 (C data,128,2n+1 )=F 7 (C data,128,2(n+8)+1 )=F 7 (C data,128,2(n+16)+1 )=C control,256,103−n , (for 0≦n≦7) and F 7 (C data,128,64+2n+1 )=F 7 (C data,128,64+2(n+8)+1 )=F 7 (C data,128,64+2(n+16)+1 )=C control,256,207−n , (for 0≦n≦7), where a spreading factor of the data signal is SF=128, a spreading factor of the control signal is SF=256, and k=0, 1, 2, 3, . . . , 23.

11. A channel allocation method in a CDMA (Code Division Multiple Access) communication system, comprising the steps of:

selecting a node among a plurality of nodes having a SF (Spreading Factor) supportable for a maximum data rate in the CDMA communication system;

allocating codes corresponding to child nodes having the selected node as a mother node to a control channel; and

allocating codes corresponding to non-selected nodes and codes corresponding to child nodes having the non-selected nodes as a mother node to a data channel corresponding to the control channel,

wherein the codes allocated to a plurality of control channels maintain orthogonality with each other, and the codes allocated to a plurality of data channels are also orthogonal with each other.

12. A channel transmission method for a user equipment (UB) in a CDMA (Code Division Multiple Access) communication system, comprising the steps of:

receiving a node having a specific SF (Spreading Factor) allocated from a UTRAN (UMTS (Universal Mobile Terrestrial System) Terrestrial Radio Access Network);

selecting a node among at least one node having an identical SF as the received node;

allocating a child node among a plurality of child nodes having the selected node as a mother node to a control channel;

allocating a node among the received node and child nodes having the received node as a mother node to a data channel corresponding to the control channel;

spreading a control signal with a code corresponding to the node allocated to the control channel; and

spreading a data signal with a code corresponding to the node allocated to the data channel,

wherein a code corresponding to the selected node maintains orthogonality with a code corresponding to the received node.

13. A channel transmission apparatus for a user equipment (UE) in a CDMA (Code Division Multiple Access) communication system, comprising:

an input unit for receiving a node having a specific SF (Spreacting Factor) allocated from a UTRAN (UMTS (Universal Mobile Terrestrial System) Terrestrial Radio Access Network);

an OVSF (Orthogonal Variable Spreading Factor) code allocating device for selecting a node among one or more nodes having the same SF to the received node, allocating a code corresponding to anode among child nodes having the selected node as a mother node to a control channel, and allocating a code corresponding to a node among the received node and child nodes having the received node as a mother node to a data channel corresponding to the control channel;

an OVSF code generator for generating the code allocated to the control channel and the code allocated to the data channel;

a first spreader for spreading a control signal with the generated code for the control channel; and

a second spreader for spreading a data signal with the generated code for the data channel,

wherein a code corresponding to the selected node maintains orthogonality with a code corresponding to the received node.

14. A channel reception apparatus for a UTRAN(UMTS (Universal Mobile Terrestrial System) Terrestrial Radio Access Network) in a CDMA (Code Division Multiple Access) communication system, comprising:

a memory for storing nodes arranged in a tree form for each SF (Spreading Factor);

an OVSF (Orthogonal Variable Spreading Factor) code allocating device for acquiring a node among at least one node having an identical SF to a random node allocated to a specific UE, allocating a node among child nodes having the acquired node as a mother node to a control channel, and allocating a node among a random node and child nodes having the random node as a mother node to the data channel corresponding to the control channel;

an OVSF code generator for generating a first code corresponding to the node allocated to the control channel and a second code corresponding to the node allocated to the data channel;

a first despreader for despreading a control signal received from the specific UE with the first code; and

a second despreader for despreading a data signal received from the specific UE with the second code,

wherein a code corresponding to the acquired node maintains orthogonality with a code corresponding to the reccived node.