Automatic determination point for random access channel partitioning scheme

• US 6,697,346 B1
• Filed: 10/04/1999
• Issued: 02/24/2004
• Est. Priority Date: 10/05/1998
• Status: Expired due to Term

• Current Assignee: Thomson Licensing SAS (Vantiva SA)
• Original Assignee: Sony International Europe Gmbh (Sony Group Corp.)
• Inventors: James, Paul, Halton, John
• Primary Examiner(s): Tran, Sinh
• Assistant Examiner(s): RAMOS FELICIANO, ELISEO
• Application Number:
  US09/412,186
• Time in Patent Office: 1,604 Days
• Field of Search: 370/328, 370/329, 370/341, 370/345, 370/347, 370/348, 370/335, 370/342, 370/441, 370/336, 370/442, 370/443, 370/337, 455/562, 455/561
• US Class Current: 370/335
• CPC Class Codes: H04B 7/216 Code division or spread-spectrum multiple access [CDMA, SSMA]
• CPC Class Codes: H04W 74/02 Hybrid access

Abstract

The present invention relates to a method and to devices (26, 27) for transmitting and receiving data in a code division multiple access telecommunication system. A random access time window (1) is provided, which comprises a plurality of random access slots for transmitting random access data from at least one first communication device (27) to a second communication device (26). A partition point is determined, which defines a number of contention based random access slots and a number of reservation based random access slots in the random access time window on the basis of statistical information generated in at least one first communication device (27). The random access time window (1) is partitioned in a first and a second section on the basis of said partition point, whereby the first section contains contention based random access slots and the second section contains reservation based random access slots. The present invention thereby allows to dynamically adapt the random access time window resources to changing requirements and an optimal utilization of the resources.

Claims

1. Method for transmitting and receiving data in a code division multiple access telecommunication system, comprising the steps of

providing a random access time window (1) comprising a plurality of random access slots for transmitting random access data from at least one first communication device (27, 28) to a second communication device (26),

determining a partition defining a number of contention based random access slots and a number of reservation based random access slots in the random access time window on the basis of statistical information generated in the at least one first communication device (27, 28), and

partitioning the plurality of random access time slots into a first and a second section (2, 3) on the basis of said partition, whereby the first section contains one or more of the plurality of random access time slots which are designated as contention based random access slots and the second section (3) contains the remainder of the plurality of random access time slots which are designated as reservation based random access slots;

whereby the random access time window is partitioned in two dimensions, time and code.

2. Method for transmitting and receiving data according to claim 1, characterized in, that each random access slot in said random access time window is defined by a time offset value and a preamble code.

3. Method for transmitting and receiving data according to claim 1, characterized in, that said statistical information is information on contention based random access attempts in said at least one first communication device (27, 28).

4. Method for and receiving data according to claim 3, characterized in, that said statistical information is the number of failed contention based random access attempts within a predetermined period of time.

5. Method for transmitting and receiving data according to claim 4, characterized in, that in said step of determining the partition the number of the contention based random access slots in said random access time window is increased in case that the number of failed contention based random access attempts reaches a predetermined contention threshold value.

6. Method for transmitting and receiving data according to claim 4, characterized in, that in said step of determining the partition the number of the contention based random access slots in said random access time window is decreased in case that the number of failed contention based random access attempts falls under a predetermined reservation threshold value.

7. Method for transmitting and receiving data according to claim 6, characterized in, that said reservation threshold value is smaller than said contention threshold value, whereby a buffer space is provided in between.

8. Method for transmitting and receiving data according to claim 1, characterized in, that in said determining step the partition is calculated arithmetically.

9. Method for transmitting and receiving data according to claim 1, characterized in,

that said second communication device periodically broadcasts information about the partition of said random access time window to the at least one first communication device (27, 28).

10. Device (27, 28) for transmitting and receiving data in a code division multiple access telecommunication system, in which a random access time window (1) comprising a plurality of random access slots for transmitting random access data is provided, the plurality of random access slots being partitioned in a first and second section (2, 3), whereby the first section (2) contains one or more of the plurality of random access slots which are designated as contention based random access slots and the second section (3) contains the remainder of the random access slots which are designated as reservation based random access slots, with means (34) for randomly choosing a random access slot from said first section, means (33) for transmitting random access data in said chosen random access slot, and means (41) for generating statistical information on contention based random access attempts, whereby the random access time window is partitioned in two dimensions, time and code.

11. Device for transmitting and receiving data according to claim 10, characterized in, that said means (41) for generating statistical information determines the number of failed contention based random access attempts within a predetermined period of time.

12. Device for transmitting and receiving data according to claim 10, characterized in, that said means (41) for generating statistical information generates a corresponding information signal to be transmitted by said means (33).

13. Device for transmitting and receiving according to claim 10, characterized by

means (32) for receiving periodically broadcast information about the partition of said random access time window (1).

14. Device for transmitting and receiving data according claim 10, characterized in, that each random access slot in said random access time window is defined by a time offset value and a preamble code.

15. Device (26) for transmitting and receiving data in a code division multiple access telecommunication system, in which a random access time window (1) comprising a plurality of random access slots for transmitting random access data is provided, with

means (42) for determining a partition defining a number of contention based random access slots and a number of reservation based random access slots in the random access time window on the basis of received statistical information,

means (38) for partitioning the plurality of random access slots in a first and second section (2, 3) on the basis of said partition,

whereby the first section (2) contains one or more of the plurality of random access slots which are designated as contention based random access slots and the second section (3) contains the remainder of the plurality of random access time slots which are designated as reservation based random access slots, and

means (37) for broadcasting information about the partition of said random access time window (1);

whereby the random access time window is partitioned in two dimensions, time and code.

16. Device for transmitting and receiving data according to claim 15, characterized by means (36) for receiving said statistical information from at least one further device (27, 28) for transmitting and receiving data.

17. Device for transmitting and receiving data according to claim 16, characterized in, that said statistical information is information on contention based random access attempts generated in said at least one further device (27, 28).

18. Device for transmitting and receiving data according to claim 17, characterized in, that said statistical information is the number of failed contention based random access attempts of said at least one further device (27, 28) within a predetermined period of time.

19. Device for transmitting and receiving data according to claim 18, characterized in, that in means (42) for determining the partition the number of the contention based random access slots in said random access time window is increased in case that the number of failed contention based random access attempts reaches a predetermined contention threshold value.

20. Device for transmitting and receiving data according to claim 18, characterized in, that in said means (42) for determining the partition the number of the contention based random access slots in said random access time window is decreased in case that the number of failed contention based random access attempts falls under a predetermined reservation threshold value.

21. Device for transmitting and receiving data according to claim 20, characterized in, that said reservation threshold value is smaller than said contention threshold value, whereby a buffer space is provided in between.

22. Device for transmitting and receiving data according to claim 15, characterized in, that in said determining means (42) the partition is calculated arithmetically.

23. Device for transmitting and receiving data according to claim 15, characterized in, that each random access slot in said random access time window is defined by a time offset value and a preamble code.