Ranging method in a broadband wireless access communication system

• US 20050041573A1
• Filed: 07/30/2004
• Published: 02/24/2005
• Est. Priority Date: 07/30/2003
• Status: Abandoned Application

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Song, Bong-Gee, Cho, Min-Hee, Eom, Kwang-Seop
• Application Number:
  US10/909,245
• Publication Number:
  US 20050041573A1
• Time in Patent Office: Days
• US Class Current: 370/208
• CPC Class Codes: H04L 5/023 Multiplexing of multicarrier modulation signals multicarrier modulation H04L27/2601
• CPC Class Codes: H04W 74/002 Transmission of channel access control information
• CPC Class Codes: H04W 74/0833 Random access procedures, e.g. with 4-step access
• CPC Class Codes: H04W 74/0866 using a dedicated channel for access
• CPC Class Codes: H04W 8/26 Network addressing or numbering for mobility support

Abstract

A method for transmitting a ranging code from a base station to subscriber stations to prevent collision during a random access by the subscriber stations in an Orthogonal Frequency Division Multiplexing/Orthogonal Frequency Division Multiple Access (OFDM/OFDMA) communication system. The method includes allocating connection identifiers (CIDs) for identifying the subscriber stations, allocating group IDs to the CIDs to divide the subscriber stations into a predetermine number of groups, and allocating ranging codes for distinguishing subscriber stations in a group corresponding to each of the allocated group IDs.

Claims

1. A method for transmitting a ranging signal from a base station to subscriber stations to prevent collisions during a random access by the subscriber stations in an Orthogonal Frequency Division Multiplexing/Orthogonal Frequency Division Multiple Access (OFDM/OFDMA) communication system, the method comprising the steps of:

allocating connection identifiers (CIDs) for identifying the subscriber stations;

allocating group IDs to the CIDs to divide the subscriber stations into a predetermine number of groups; and

allocating ranging codes for distinguishing the subscriber stations in a group corresponding to each of the allocated group IDs.

2. The method of claim 1, wherein the transmitted ranging signal is transmitted for periodic ranging.

3. The method of claim 1, wherein the transmitted ranging signal is transmitted for bandwidth request ranging.

4. The method of claim 1, wherein the CID is one of a basic CID, a primary management CID, and a secondary management CID.

5. The method of claim 1, wherein the CID is allocated by the base station, and transmitted to the subscriber station in an initial ranging procedure.

6. The method of claim 5, wherein the CID is transmitted through a ranging response (RNG-RSP) message transmitted from the base station to the subscriber station in the initial ranging procedure.

7. The method of claim 1, wherein a transmission time and a type of the ranging code are determined by receiving the CID by the subscriber station and using a method shared with the base station through the received CID.

8. The method of claim 1, wherein a transmission time and a type of the ranging code are determined from a CID of the subscriber station by the base station, and the determined transmission time and type of the ranging code are transmitted to the subscriber station.

9. The method of claim 1, further comprising the steps of:

mapping a ranging transmission group to a ranging slot for the ranging code; and

allocating the transmission group according to the CID.

10. The method of claim 9, wherein mapping information between the ranging slot and the ranging transmission group is transmitted through an uplink MAP (UL-MAP) message transmitted from the base station to the subscriber station.

11. A method for transmitting a ranging signal to a base station by a subscriber station in a Broadband Wireless Access (BWA) communication system that supports Orthogonal Frequency Division Multiplexing/Orthogonal Frequency Division Multiple Access (OFDM/OFDMA) and transmits ranging information from the base station to the subscriber station to adjust at least one of time synchronization, frequency synchronization, and a power level between the base station and the subscriber station, the method comprising the steps of:

receiving a connection ID (CID) allocated to the subscriber station from the base station;

determining a transmission time of a ranging code by the subscriber station and a type of the ranging code, from the CID; and

transmitting the determined ranging code to the base station at the determined ranging signal transmission time.

12. The method of claim 11, wherein the transmitted ranging signal is transmitted for periodic ranging.

13. The method of claim 11, wherein the transmitted ranging signal is transmitted for bandwidth request ranging.

14. The method of claim 11, wherein the CID is one of a basic CID, a primary management CID, and a secondary management CID.

15. The method of claim 11, wherein the CID is allocated by the base station, and transmitted to the subscriber station in an initial ranging procedure.

16. The method of claim 15, wherein the CID is transmitted through a ranging response (RNG-RSP) message transmitted from the base station to the subscriber station in the initial ranging procedure.

17. The method of claim 11, wherein the transmission time of the ranging code and the type of the ranging code are determined by receiving the CID by the subscriber station and using a method shared with the base station through the received CID.

18. The method of claim 11, wherein the transmission time of the ranging signal and the type of the ranging code are determined from a CID of the subscriber station by the base station, and the determined transmission time and type of the ranging code are transmitted to the subscriber station.

19. The method of claim 11, further comprising the steps of:

mapping a ranging transmission group to a ranging slot for transmitting the ranging signal; and

allocating the transmission group to the CID.

20. The method of claim 19, wherein mapping information between the ranging slot and the ranging transmission group is transmitted through an uplink MAP (UL-MAP) message transmitted from the base station to the subscriber station.

21. A method for transmitting a ranging code to a base station by a subscriber station in a Broadband Wireless Access (BWA) communication system that supports Orthogonal Frequency Division Multiplexing/Orthogonal Frequency Division Multiple Access (OFDM/OFDMA) and transmits ranging information from the base station to the subscriber station to adjust at least one of time synchronization, frequency synchronization, and a power level between the base station and the subscriber station, the method comprising the steps of:

receiving a connection ID (CID) allocated to the subscriber station from the base station;

allocating a transmission time of the ranging code to a plurality of transmission groups;

determining a transmission time of the ranging code for the subscriber station as one of the transmission groups according to the received CID;

determining a type of the transmission ranging code such that the subscriber stations should have different ranging codes in a same transmission group; and

transmitting the determined ranging code at a transmission time corresponding to the determined transmission group.

22. The method of claim 21, wherein the transmitted ranging code is transmitted for initial ranging.

23. The method of claim 21, wherein the transmitted ranging code is transmitted for bandwidth request ranging.

24. The method of claim 21, wherein the CID is one of a basic CID, a primary management CID, and a secondary management CID.

25. The method of claim 21, wherein the CID is allocated by the base station, and transmitted to the subscriber station in an initial ranging procedure.

26. The method of claim 25, wherein the CID is transmitted through a ranging response (RNG-RSP) message transmitted from the base station to the subscriber station in the initial ranging procedure.

27. The method of claim 21, wherein a transmission group allocated to the transmission time is allocated by a slot for dividing one transmission frame into a plurality of transmission periods.

28. The method of claim 27, wherein mapping information between the ranging slot and the ranging transmission group is transmitted through an uplink MAP (UL-MAP) message transmitted from the base station to the subscriber station.

29. The method of claim 21, wherein the number of transmission groups mapped to the transmission time is determined considering at least one of a number of subscriber stations in a corresponding cell, a maximum delay time, and the number of ranging codes available in one slot.

30. The method of claim 21, wherein types of the transmission group and the ranging code are determined from the CID in accordance with,

CID=α

_code ·

N+β

<sub>G —

ID</sub>

where α

_code denotes a unique number of a ranging code, and β

<sub>G—

ID</sub> denotes a group ID.

31. A method for transmitting a ranging code to a base station by a subscriber station in a Broadband Wireless Access (BWA) communication system that supports Orthogonal Frequency Division Multiplexing/Orthogonal Frequency Division Multiple Access (OFDM/OFDMA) and transmits ranging information from the base station to the subscriber station to adjust at least one of time synchronization, frequency synchronization, and a power level between the base station and the subscriber station, the method comprising the steps of:

allocating, by the base station, a transmission time of the ranging code to a plurality of transmission groups;

receiving information on a transmission time of the ranging code for the subscriber station, determined as one of the transmission groups according to a connection ID (CID) of the subscriber station;

receiving information on a type of the transmission ranging code determined such that the subscriber stations should have different ranging codes in a same transmission group; and

transmitting the determined ranging code at a transmission time corresponding to the determined transmission group.

32. The method of claim 31, wherein the transmitted ranging code is transmitted for initial ranging.

33. The method of claim 31, wherein the transmitted ranging code is transmitted for bandwidth request ranging.

34. The method of claim 31, wherein the CID is one of a basic CID, a primary management CID, and a secondary management CID.

35. The method of claim 31, wherein the CID is transmitted to the subscriber station in an initial ranging procedure.

36. The method of claim 35, wherein the CID is transmitted through a ranging response (RNG-RSP) message transmitted from the base station to the subscriber station in the initial ranging procedure.

37. The method of claim 31, wherein a transmission group allocated to the transmission time is allocated by a slot for dividing one transmission frame into a plurality of transmission periods.

38. The method of claim 37, wherein mapping information between the ranging slot and the ranging transmission group is transmitted through an uplink MAP (UL-MAP) message transmitted from the base station to the subscriber station.

39. The method of claim 31, wherein the number of transmission groups mapped to the transmission time is determined considering at least one of a number of subscriber stations in a corresponding cell, a maximum delay time, and the number of ranging codes available in one slot.

40. The method of claim 31, wherein types of the transmission group and the ranging code are determined from the CID in accordance with,

CID=α

_code ·

N+β

<sub>G —

ID</sub>

where α

_code denotes a unique number of a ranging code, and β

<sub>G—

ID</sub> denotes a group ID.