Apparatus and method for assigning a common packet channel in a CDMA communication system

• US 20010026543A1
• Filed: 02/16/2001
• Published: 10/04/2001
• Est. Priority Date: 02/16/2000
• Status: Abandoned Application

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Choi, Sung-Ho, Koo, Chang-Hoi, Hwang, Sung-Oh, Lee, Hyun-Woo, Kim, Kyou-Woong, Mun, Hyun-Jung, Park, Seong-III
• Application Number:
  US09/784,914
• Publication Number:
  US 20010026543A1
• Time in Patent Office: Days
• US Class Current: 370/335
• CPC Class Codes: H04B 1/7075 with code phase acquisition
• CPC Class Codes: H04B 7/2628 using code-division multiple access [CDMA] or spread spectrum multiple access [SSMA] H04B7/2618 takes precedence
• CPC Class Codes: H04J 13/0044 OVSF [orthogonal variable spreading factor]
• CPC Class Codes: H04J 13/20 having an orthogonal variable spreading factor [OVSF]
• CPC Class Codes: H04W 72/02 Selection of wireless resources by user or terminal
• CPC Class Codes: H04W 72/20 Control channels or signalling for resource management
• CPC Class Codes: H04W 72/21 in the uplink direction of a wireless link, i.e. towards the network
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal

Abstract

Disclosed is a method for assigning a channel to a UE by a UTRAN in a CDMA communication system. The UTRAN receives a selected one of a plurality of access preamble signatures from the UE, and selects one of a plurality of channel assignment signatures associated with the received access preamble signature in order to assign one of a plurality of physical common packet channels (PCPCHs) unused in the UTRAN. The UTRAN selects one of the access preamble signatures depending on a maximum data rate required when the UE transmits data. Further, the UTRAN selects one of the unused PCPCH channels depending on the received access preamble signature and the selected channel assignment signature.

Claims

1. A method for assigning a channel to a UE (user equipment) by a UTRAN (UMTS (Universal Mobile Telecommunications System) Terrestrial Radio Access Network) in a CDMA (Code Division Multiple Access) communication system, the method comprising the steps of:

receiving a access preamble signature from the UE; and

selecting one of a plurality of channel assignment signatures associated with the received access preamble signature in order to assign one of a plurality of physical common packet channels (PCPCHs) unused in the UTRAN.

2. The method as claimed in

claim 1

, wherein the UTRAN selects one of the channel assignment signatures depending on a maximum data rate required when the UE transmits data.

3. The method as claimed in

claim 1

, further comprising the step of selecting one of the PCPCHs unused in the UTRAN depending on the received access preamble signature and the selected channel assignment signature for receiving a packet data from the UE.

4. The method as claimed in

claim 3

, wherein the PCPCH selecting step comprises the steps of:

determining a number P_SF of PCPCHs capable of supporting a maximum data rate required when the UE transmits data out of the unused PCPCHs;

determining a number S_SF of access preamble signature available for the maximum data rate required when the UE transmits data;

determining a number T_SF of channel assignment signatures available for the maximum data rate depending on the number P_SF of the PCPCHs;

calculating a minimum positive number M_SF out of positive numbers which are determined to have a remainder of ‘

0’

when multiplying the number S_SF of the access preamble signatures by a given positive number and dividing the multiplied value by the number P_SF of the PCPCHs;

calculating a specific coefficient ‘

n’

satisfying the following equation

n*M_SF*S_SF≦

i+j*S_SF≦

(n+1)*M_SF*S_SF

where i denotes an access preamble signature number and j denotes a channel allocation message number; and

selecting one PCPCH'"'"'s number ‘

k’

out of the PCPCHs unused in the UTRAN by satisfying the following equation

k={[(i+n) mod S_SF]+j*S_SF} mod P_SF

.

5. The method as claimed in

claim 4

, further comprising the steps of:

calculating a specific coefficient ‘

m’

for determining a data rate by satisfying the following equation

P<sub>2m−

1</sub>≦

k<

P_2m

where P<sub>2m−

1</sub> denotes a channelization code with a spreading factor 2<sup>m−

1</sup>, and P_2m denotes a channelization code with a spreading factor 2^m;

calculating an uplink scrambling code'"'"'s number by satisfying the following equation $\lfloor <br><br>\underset{2\le <br><br>a<<br><br>m-1}{\sum <br><br>}<br><br>\text{\hspace{1em}<br><br>}<br><br>\left(P_{2^a}-P_{2^{2<br><br>a-1}}\right)/2^{a-1}+\left(k-P_{2^{m-1}}\right)/2^m\rfloor <br><br>$

where, α

is an integer numbers;

calculating a heading node by satisfying the following equation $\left(\underset{2\le <br><br>a<<br><br>m-1}{\sum <br><br>}<br><br>\left(P_{2^a}-P_{2^{a-1}}\right)*2^{m-a}+k+P_{2^{m-1}}\right)/2^m;<br><br>$

selecting a channelization code with a spreading factor corresponding to the maximum data rate from the heading node and determining the selected channelization code as a channelization code to be used by the UE.

6. The method as claimed in

claim 1

, wherein the channel assignment signature (j) is selected by satisfying following equation;

n*M_SF*S_SF≦

i+j*S_SF<

(n+1)*M_SF*S_SF

where, i is number of the access preamble signature, the S_SF is a number of access preamble signatures assigned for the maximum data rate determined by the access preamble signature, the M_SF is a minimum positive number (M_SF) out of positive numbers which are determined to have a remainder of ‘

0’

when multiplying the number S_SF by a given positive number and dividing the multiplied value by a number P_SF representing number of PCPCHs assigned to support the maximum data rate, the n indicates how many times a period of M_SF has been repeated.

7. The method as claimed in

claim 6

, wherein a PCPCH (k) is determined by satisfying following equation;

k={[(i+n) mod S_SF]+j*S_SF} mod P_SF.

8. A method for assigning a channel to a UE (user equipment) by a UTRAN (UMTS (Universal Mobile Telecommunications System) Terrestrial Radio Access Network) in a CDMA (Code Division Multiple Access) communication system, the method comprising the steps of:

receiving a selected one of a plurality of access preamble signatures from the UE; and

determining a specific channel assignment signature from a plurality of channel assignment signatures so as to select one of a plurality of unused PCPCHs (physical common packet channels) depending on the received access preamble signature and a channel assignment signature.

9. The method as claimed in

claim 8

, wherein the UTRAN selects one of the channel assignment signatures depending on a maximum data rate determined by the access preamble signature.

10. The method as claimed in

claim 9

, wherein the channel assignment signature (j) is selected by satisfying following equation;

n*M_SF*S_SF≦

i+j*S_SF≦

(n+1)*M_SF*S_SF

where, i is number of the access preamble signature, the S_SF is a number of access preamble signatures assigned for the maximum data rate determined by the access preamble signature, the M_SF is a minimum positive number (M_SF) out of positive numbers which are determined to have a remainder of ‘

0’

when multiplying the number S_SF by a given positive number and dividing the multiplied value by a number P_SF representing number of PCPCHs assigned to support the maximum data rate and the n indicates how many times a period of M_SF has been repeated.

11. The method as claimed in

claim 10

, further comprising the step of selecting one of the PCPCHs unused in the UTRAN depending on the received access preamble signature and the selected channel assignment signature for receiving a packet data from the UB.

12. The method as claimed in

claim 11

, wherein the selected PCPCH (k) is determined by satisfying following equation;

k={[(i+n) mod S_SF]+j*S_SF} mod P_SF.

13. The method as claimed in

claim 9

, wherein the PCPCH selecting step comprises the steps of:

determining a number P_SF of PCPCHs capable of supporting a maximum data rate required when the UE transmits data out of the unused PCPCHs;

determining a number S_SF of access preamble signatures available for the maximum data rate required when the UE transmits data;

determining a number T_SF of channel assignment signatures available for the maximum data rate depending on the number P_SF of the PCPCHs;

calculating a minimum positive number M_SF out of positive numbers which are determined to have a remainder of ‘

0’

when multiplying the number S_SF of the access preamble signatures by a given positive number and dividing the multiplied value by the number P_SF of the PCPCHs;

calculating a specific coefficient ‘

n’

satisfying the following equation

n*M_SF *S_SF≦

i+j*S_SF≦

(n+1)*M_SF*S_SF

where i denotes an access preamble signature number and j denotes a channel allocation message number; and

selecting one PCPCH'"'"'s number ‘

k’

out of the PCPCHs unused in the UTRAN by satisfying the following equation

k={[(i+n) mod S_SF]+j*S_SF}mod P_SF.

14. The method as claimed in

claim 13

, further comprising the steps of:

calculating a specific coefficient ‘

m’

for determining a data rate by satisfying the following equation

P<sub>2n−

1</sub>≦

k≦

P_2m

where P<sub>2m−

1</sub> denotes a channelization code with a spreading factor 2<sup>m−

1</sup>, and P_2m denotes a channelization code with a spreading factor 2^m;

calculating an uplink scrambling code'"'"'s number by satisfying the following equation $\lfloor <br><br>\underset{2\le <br><br>a<<br><br>m-1}{\sum <br><br>}<br><br>\left(P_{2^a}-P_{2^{a-1}}\right)/2^{a-1}+\left(k+P_{2^{m-1}}\right)/2^m\rfloor <br><br>$

where, a is an integer numbers;

calculating a heading node by satisfying the following equation $\left(\underset{2\le <br><br>a<<br><br>m-1}{\sum <br><br>}<br><br>\left(P_{2^a}-P_{2^{a-1}}\right)*2^{m-a}+k+P_{2^{m-1}}\right)/2^m;<br><br>$

and

selecting a channelization code with a spreading factor corresponding to the maximum data rate from the heading node and determining the selected channelization code as a channelization code to be used by the UE.

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

upon generation of data to be transmitted over a PCPCH channel, selecting one of a plurality of access preamble signatures and transmitting the selected access preamble signature to a UTRAN;

receiving a selected one of a plurality of channel assignment signatures from the UTRAN; and

determining a PCPCH channel for transmitting the data depending on the selected access preamble signature and the received channel assignment signature.

16. The method as claimed in

claim 15

, wherein the UE selects one of the access preamble signatures depending on a maximum data rate required when transmitting the data.

17. The method as claimed in

claim 15

, wherein the PCPCH (k) is determined by satisfying following equation;

k={[(i+n) mod S_SF]+j*S_SF}mod P_SF.

where, i is a number of the access preamble signature, the j is a number of the received channel assignment signature, the S_SF is a number of access preamble signatures assigned for the maximum data rate determined by the access preamble signature, the P_SF representing a number of PCPCHs assigned to support the maximum data rate, and the n indicates how many times a period of M_SF, which represent a minimum positive number out of positive numbers which are determined to have a remainder of ‘

0’

when multiplying the number S_SF by a given positive number and dividing the multiplied value by a number P_SF, has been repeated.

18. The method as claimed in

claim 15

, wherein the selecting step comprises the steps of:

determining a number P_SF of PCPCHs capable of supporting a maximum data rate required when the UE transmits data out of the unused PCPCHs;

determining a number S_SF of access preamble signatures available for the maximum data rate required when the UE transmits data;

determining a number T_SF of channel assignment signatures available for the maximum data rate depending on the number P_SF of the PCPCHs;

calculating a minimum positive number M_SF out of positive numbers which are determined to have a remainder of ‘

1’

when multiplying the number S_SF of the access preamble signatures by a given positive number and dividing the multiplied value by the number P_SF of the PCPCHs;

calculating a specific coefficient ‘

n’

satisfying the following equation

n*M_SF*S_SF≦

i+j*S_SF≦

(n+1)*M_SF*S_SF

where i denotes an access preamble signature number and j denotes a channel allocation message number; and

selecting one PCPCH'"'"'s number ‘

k’

out of the PCPCHs unused in the UTRAN by satisfying the following equation

k={[(i+n) mod S_SF]+j*S_SF} mod P_SF.

19. The method as claimed in

claim 18

, further comprising the steps of:

calculating a specific coefficient ‘

m’

for determining a data rate by satisfying the following equation

P<sub>2m−

1</sub>≦

k<

P_2m

where P<sub>2m−

1</sub> denotes a channelization code with a spreading factor 2<sup>m−

1</sup>, and P_2m denotes a channelization code with a spreading factor 2^m;

calculating an uplink scrambling code'"'"'s number by satisfying the following equation $\lfloor <br><br>\underset{2\le <br><br>a<<br><br>m-1}{\sum <br><br>}<br><br>\left(P_{2^a}-P_{2^{a-1}}\right)/2^{a-1}+\left(k+P_{2^{m-1}}\right)/2^m\rfloor <br><br>$

where, a is an integer numbers;

calculating a heading node by satisfying the following equation $\left(\underset{2\le <br><br>a<<br><br>m-1}{\sum <br><br>}<br><br>\left(P_{2^a}-P_{2^{a-1}}\right)*2^{m-a}+k+P_{2^{m-1}}\right)/2^m;<br><br>$

and

selecting a channelization code with a spreading factor corresponding to the maximum data rate from the heading node and determining the selected channelization code as a channelization code to be used by the UE.