Methods and apparatus for dynamically assigning time slots in a wireless communication system

• US 7,161,922 B2
• Filed: 08/13/2004
• Issued: 01/09/2007
• Est. Priority Date: 06/23/1999
• Status: Expired due to Term

• Current Assignee: Clearwire Ip Holdings LLC (Deutsche Telekom AG)
• Original Assignee: Clearwire Corporation (Deutsche Telekom AG)
• Inventors: Gibbons, David B., Hong, Liang A., Hoole, Elliott, Moinzadeh, Kamyar, Gormley, Eamonn
• Primary Examiner(s): Patel; Ajit
• Application Number:
  US10/917,825
• Publication Number:
  US 20050088990A1
• Time in Patent Office: 879 Days
• Field of Search: 370/468, 370/342, 370/442, 370/461, 370/462, 370/503, 370/392, 370/594, 370/389, 370/335, 370/336, 370/337
• US Class Current: 370/337
• CPC Class Codes: H04W 24/10 Scheduling measurement reports ; Arrangements for measurement reports
• CPC Class Codes: H04W 72/02 Selection of wireless resources by user or terminal
• CPC Class Codes: H04W 72/0446 Resources in time domain, e.g. slots or frames
• CPC Class Codes: H04W 74/00 Wireless channel access

Abstract

A wireless communication system having a base unit and a plurality of remote transceiver units utilizes a dynamic time slot assignment scheme for channel access. The base unit receives and processes a channel access request message from a remote transceiver unit and prepares a channel measurement request message in response. If an M^th time slot of a time frame is available, the base unit sends this message in the M^th time slot and receives a message having channel measurement data in the M^th time slot of the next time frame. On the other hand, if the M^th time slot of the time frame is already reserved, the base unit sends the message in an N^th time slot of the time frame and receives a message having the channel measurement data in the N^th time slot of the next time frame. The base unit selects, based on the channel measurement data, an appropriate channel for communication for the remote transceiver unit. Continuing with use of the dynamic slot assignment, the base unit sends a message having a channel identifier associated with the selected channel and receives an acknowledgement from the remote transceiver unit in response.

Claims

1. A computer memory having computer instructions embedded thereon for dynamically assigning time slots between a base unit and a transceiver unit of a wireless communication system having a predetermined number of time slots per time frame, the computer readable medium comprising instructions that cause one or more computers to:

receive a first message;

process the first message and generate a second message in response thereto;

when a first selected time slot of a time frame is available;

send the second message that is responsive to the first message in the first time slot;

receive a third message that is responsive to the second message in the first time slot of a subsequent time frame;

when the first time slot of the time frame is unavailable;

send the second message that is responsive to the first message in a second time slot of the time frame, the second time slot being different from the first time slot in the time frame; and

receive the third message that is responsive to the second message in the second time slot of the subsequent time frame.

2. The computer memory of claim 1, further comprising computer instructions that cause the one or more computers to:

when the first and second time slots of the time frame are unavailable;

send the second message that is responsive to the first message in a third time slot of the time frame, the third time slot being different from the first and second time slots in the time frame; and

receive the third message that is responsive to the second message in the third time slot of the subsequent time frame.

3. The computer memory of claim 1, further comprising computer instructions that cause the one or more computers to:

reserve the first time slot of the subsequent time frame prior to receiving the third message when the first time slot of the time frame is available; and

reserve the second time slot of the subsequent time frame prior to receiving the third message when the first time slot of the time frame is unavailable.

4. The computer memory of claim 1, further comprising computer instructions that cause the one or more computers to:

reserve the first time slot of the subsequent time frame prior to receiving the third message when the first time slot of the time frame is available;

unreserve the first time slot after receiving the third message in the first time slot of the subsequent time frame;

reserve the second time slot of the subsequent time frame prior to receiving the third message when the first time slot of the time frame is unavailable; and

unreserve the second time slot after receiving the third message in the second time slot of the subsequent time frame.

5. The computer memory of claim 1 wherein the first message comprises a Common Access channel (CAC) message and the second message comprises a Common Link Channel (CLC) message.

6. The computer memory of claim 1 wherein the first message comprises a channel access request for communication.

7. The computer memory of claim 1 wherein the first message comprises a channel access request for communication, the second message comprises a channel measurement request, and the third message comprises channel measurement data.

8. The computer memory of claim 1 wherein the first selected time slot is one of the predetermined number of available sequential time slots.

9. The computer memory of claim 8 wherein the first selected time slot is the first sequential time slot.

10. A computer memory having computer instructions embedded thereon for dynamically assigning time slots in wireless communication system, the computer readable medium comprising instructions that cause one or more computers to:

identify a next available time slot time frame having plurality of time slots;

reserve the identified time slot of the time frame;

send a first message in the reserved time slot of the time frame;

receive a second message that is responsive to the first message in the corresponding reserved time slot of a following time frame; and

unreserve the reserved time slot for subsequent use.

11. The computer memory of claim 10 wherein the first and the second message comprise messages for call establishment.

12. A method for dynamically assigning time slots between a base unit and a transceiver unit of a wireless communication system having a predetermined number of time slots per time frame, the method comprising:

receiving a first message;

processing the first message and generating a second message in response thereto;

when a first selected time slot of a time frame is available;

sending the second message that is responsive to the first message in the first time slot;

receiving a third message that is responsive to the second message in the first time slot of a subsequent time frame;

when the first time slot of the time frame is unavailable;

sending the second message that is responsive to the first message in a second time slot of the time frame, the second time slot being different from the first time slot in the time frame; and

receiving the third message that is responsive to the second message in the second time slot of the subsequent time frame.

13. The method claim 12, further comprising:

when the first and second time slots of the time frame are unavailable;

sending the second message that is responsive to the first message in a third time slot of the time frame, the third time slot being different from the first and second time slots in the time frame; and

receiving the third message that is responsive to the second message in the third time slot of the subsequent time frame.

14. The method of claim 12, further comprising:

reserving the first time slot of the subsequent time frame prior to receiving the third message when the first time slot of the time frame is available; and

reserving the second time slot of the subsequent time frame prior to receiving the third message when the first time slot of the time frame is unavailable.

15. The method of claim 12, further comprising:

reserving the first time slot of the subsequent time frame prior to receiving the third message when the first time slot of the time frame is available;

unreserving the first time slot after receiving the third message in the first time slot of the subsequent time frame;

reserving the second time slot of the subsequent time frame prior to receiving the third message when the first time slot of the time frame is unavailable; and

unreserving the second time slot after receiving the third message in the second time slot of the subsequent time frame.

16. The method of claim 12 wherein the first message comprises a Common Access channel (CAC) message and the second message comprises a Common Link Channel (CLC) message.

17. The method of claim 12 wherein the first message comprises a channel access request for communication.

18. The method of claim 12 wherein the first message comprises a channel access request for communication, the second message comprises a channel measurement request, and the third message comprises channel measurement data.

19. The method of claim 12 wherein the first selected time slot is one of the predetermined number of available sequential time slots.

20. The method of claim 19 wherein the first selected time slot is the first sequential time slot.