Scheduling packet transmissions

• US 8,644,321 B2
• Filed: 09/15/2004
• Issued: 02/04/2014
• Est. Priority Date: 09/16/2003
• Status: Expired due to Fees

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Carlson, Neil Charles, Pankaj, Rajesh K.
• Primary Examiner(s): Moore, Jr., Michael J
• Application Number:
  US10/942,214
• Publication Number:
  US 20050058137A1
• Time in Patent Office: 3,429 Days
• Field of Search: None
• US Class Current: 370/395.42
• CPC Class Codes: H04L 47/24 Traffic characterised by specific attributes, e.g. priority or QoS
• CPC Class Codes: H04L 47/2433 Allocation of priorities to traffic types
• CPC Class Codes: H04W 28/02 Traffic management, e.g. flow control or congestion control
• CPC Class Codes: H04W 72/569 of the traffic information
• CPC Class Codes: H04W 8/04 Registration at HLR or HSS [Home Subscriber Server]

Abstract

This disclosure provides a synchronous packet manager containing a data structure for scheduling future synchronous packet transmissions and arbitrating between synchronous and asynchronous packet transmissions. Slots required for transmitting a synchronous packet are reserved by marking the corresponding entries in a synchronous packet reservation table. Rather than writing packets to many different queues, the application software fills in a single reservation table per BTS sector.

Claims

1. An apparatus for scheduling synchronous packet transmissions for transmission by a single transmission entity, comprising:

a synchronous packet manager for scheduling synchronous packet transmissions for transmission by the single transmission entity on a wireless downlink channel; and

a synchronous packet reservation table for storing slot reservations for the synchronous packet transmissions, wherein the stored slot reservations include at least one placeholder slot reservation for at least one slot on the wireless downlink channel that is unscheduled with any synchronous or asynchronous packet transmissions at the time of reservation, wherein the at least one placeholder slot reservation is configured to prohibit scheduling of any asynchronous packet for transmission by the single transmission entity on the wireless downlink channel in the at least one slot for at least a threshold period of time while the at least one slot remains unscheduled with any synchronous or asynchronous packet transmissions,

wherein the stored slot reservations for the synchronous packet transmissions are established irrespective of when synchronous packets to be transmitted are expected to arrive at the single transmission entity for transmission.

2. The apparatus in claim 1, wherein the synchronous packet manager further comprises a packet scheduler for scheduling asynchronous packet transmissions in response to the synchronous packet reservation table.

3. The apparatus in claim 1, wherein the synchronous packet reservation table is further for storing status information, wherein the status information comprises:

a priority of a synchronous packet reservation; and

a number of slots over which the packet is transmitted.

4. The apparatus in claim 1, wherein the synchronous packet manager determines a reservation to be written in the synchronous packet reservation table.

5. The apparatus in claim 1, wherein the synchronous packet manager maintains a record of a period, burst length, and num_slots for each of said reservation.

6. The apparatus in claim 2, wherein the synchronous packet manager is further configured to:

validate a start time;

find conflicting packets; and

write a synchronous packet reservation in the synchronous packet reservation table.

7. The apparatus in claim 2, wherein the asynchronous packet transmissions are traffic data.

8. The apparatus in claim 4, wherein the reservation comprises:

a priority for a placeholder entry;

a Start_Time that identifies a first slot to be reserved;

an Interlace Period that indicates a period of the reservation;

an Interlace_Burst_Length that indicates a duty cycle of the reservation; and

an Interlace_Num_Slots index that indicates a period at which the reservation is written.

9. The apparatus in claim 4, wherein the reservation is sent to multiple synchronous packet reservation tables.

27. The apparatus of claim 1, wherein the stored slot reservations correspond to slot positions where asynchronous packet transmissions cannot be scheduled irrespective of whether synchronous packet transmissions are scheduled at the slot positions.

28. The apparatus of claim 27, wherein each of the stored slot reservations repeats at a given period at the same respective slot position.

29. The apparatus of claim 27, further comprising:

a packet scheduler for scheduling asynchronous packet transmissions in response to the synchronous packet reservation table such that one or more asynchronous packet transmissions are interlaced between the slot positions of the stored slot reservations.

30. The apparatus of claim 2, wherein the synchronous packet reservation table stores the slot reservations for the synchronous packet transmissions before the synchronous packet manager schedules the synchronous packet transmissions.

31. The apparatus of claim 2, wherein, before each of the slot positions corresponding to the stored slot reservations are scheduled with synchronous packet transmissions, one or more of the asynchronous packet transmissions are scheduled in response to the synchronous packet reservation table.

32. The apparatus of claim 1, wherein, in the event that the synchronous packet manager does not schedule any synchronous packet transmissions within a particular slot corresponding to one of the stored slot reservations, the packet scheduler is permitted to schedule a given asynchronous packet transmission in the particular slot.

33. The apparatus of claim 1, wherein the synchronous packet manager schedules synchronous packets for transmission within one or more of the slot reservations only after the synchronous packets became available for transmission.

10. A method for scheduling synchronous packet transmissions for transmission by a single transmission entity, comprising:

scheduling synchronous packet transmissions for transmission by the single transmission entity on a wireless downlink channel; and

storing slot reservations for the synchronous packet transmissions, wherein the stored slot reservations include at least one placeholder slot reservation for at least one slot on the wireless downlink channel that is unscheduled with any synchronous or asynchronous packet transmissions at the time of reservation, wherein the at least one placeholder slot reservation is configured to prohibit scheduling of any asynchronous packet for transmission by the single transmission entity on the wireless downlink channel in the at least one slot for at least a threshold period of time while the at least one slot remains unscheduled with any synchronous or asynchronous packet transmissions,

wherein the stored slot reservations for the synchronous packet transmissions are established irrespective of when synchronous packets to be transmitted are expected to arrive at the single transmission entity for transmission.

11. The method in claim 10, wherein scheduling synchronous packet transmissions further comprises scheduling asynchronous packet transmissions in response to a synchronous packet reservation table.

12. The method in claim 10, wherein scheduling synchronous packet transmissions further comprises writing a reservation in the synchronous packet reservation table.

13. The method in claim 10, wherein scheduling synchronous packet transmissions further comprises maintaining a record of a period, burst length, and num_slots for each of said reservation.

14. The method in claim 11, wherein the asynchronous packet transmissions are traffic data.

15. The method in claim 12, wherein writing the reservation further comprises:

validating a start time;

finding conflicting packets; and

writing a synchronous packet reservation in the synchronous packet reservation table.

16. The method in claim 12, wherein writing the reservation is performed on multiple synchronous packet reservation tables.

36. The method of claim 10, wherein the at least one placeholder slot reservation is further configured to permit scheduling of a synchronous packet for transmission by the single transmission entity on the wireless downlink channel in the at least one slot while the at least one slot remains unscheduled with any synchronous or asynchronous packet transmissions.

37. The method of claim 10,

wherein the threshold period of time extends until N number of slots before the at least one slot, further comprising:

determining that the at least one slot remains unscheduled with any synchronous or asynchronous packet transmissions when the threshold period of time is over;

removing the at least one placeholder slot reservation in response to the determination; and

permitting one or more asynchronous packets to be scheduled for transmission by the single transmission entity on the wireless downlink channel in the at least one slot in response to the removal of the at least one placeholder slot reservation.

38. The method of claim 37, wherein N=1.

39. The method of claim 10, wherein the threshold period of time extends until the at least one slot such that the at least one placeholder slot reservation is not removed and no asynchronous packets are permitted to be scheduled in the at least slot even in the event that the at least one slot remains unscheduled with any synchronous or asynchronous packet transmissions when the at least one slot is reached.

40. The method of claim 10,

wherein the synchronous packet transmissions correspond to periodically transmitted multicast traffic, and

wherein the stored slot reservations prohibit asynchronous unicast traffic from being scheduled in any reserved slot corresponding to the stored slot reservations for at least the threshold period of time.

17. An apparatus for scheduling synchronous packet transmissions for transmission by a single transmission entity, comprising:

means for scheduling synchronous packet transmissions for transmission by the single transmission entity on a wireless downlink channel; and

means for storing slot reservations for the synchronous packet transmissions, wherein the stored slot reservations include at least one placeholder slot reservation for at least one slot on the wireless downlink channel that is unscheduled with any synchronous or asynchronous packet transmissions at the time of reservation, wherein the at least one placeholder slot reservation is configured to prohibit scheduling of any asynchronous packet for transmission by the single transmission entity on the wireless downlink channel in the at least one slot for at least a threshold period of time while the at least one slot remains unscheduled with any synchronous or asynchronous packet transmissions,

wherein the stored slot reservations for the synchronous packet transmissions are established irrespective of when synchronous packets to be transmitted are expected to arrive at the single transmission entity for transmission.

18. The apparatus in claim 17, wherein the means for scheduling synchronous packet transmissions further comprises a packet scheduler for scheduling asynchronous packet transmissions in response to a synchronous packet reservation table.

19. The apparatus in claim 17, wherein the status information comprises:

a priority of a synchronous packet reservation; and

a number of slots corresponding to a period of slots for the synchronous packet reservation over which the packet is transmitted.

20. The apparatus in claim 17, wherein the means for scheduling maintains a record of a period, burst length, and num_slots for each of said reservation.

21. The apparatus in claim 17, wherein the means for scheduling further determines a reservation to be written in the synchronous packet reservation table.

22. The apparatus in claim 17, wherein the means for scheduling synchronous packet transmissions is further configured to:

validate a start time;

find conflicting packets; and

write a synchronous packet reservation in the synchronous packet reservation table.

23. The apparatus in claim 20, wherein the reservation comprises:

a priority for a placeholder entry;

a Start_Time that identifies a first slot to be reserved;

an Interlace_Period that indicates a period of the reservation;

an Interlace_Burst_Length that indicates a duty cycle of the reservation; and

an Interlace_Num_Slots index that indicates a period at which the reservation is written.

24. The apparatus in claim 20, wherein the reservation is sent to multiple synchronous packet reservation tables.

25. An apparatus for scheduling synchronous packet transmissions for transmission by a single transmission entity, comprising:

a memory storage unit which stores instructions; and

a processor coupled to the memory storage unit, wherein the instructions configure the processor to;

schedule synchronous packet transmissions for transmission by the single transmission entity on a wireless downlink channel; and

store slot reservations for the synchronous packet transmissions, wherein the stored slot reservations include at least one placeholder slot reservation for at least one slot on the wireless downlink channel that is unscheduled with any synchronous or asynchronous packet transmissions at the time of reservation, wherein the at least one placeholder slot reservation is configured to prohibit scheduling of any asynchronous packet for transmission by the single transmission entity on the wireless downlink channel in the at least one slot for at least a threshold period of time while the at least one slot remains unscheduled with any synchronous or asynchronous packet transmissions,

wherein the stored slot reservations for the synchronous packet transmissions are established irrespective of when synchronous packets to be transmitted are expected to arrive at the single transmission entity for transmission.

26. A non-transitory computer readable storage medium which stores executable instructions, wherein the executable instructions cause a processor to:

schedule synchronous packet transmissions for transmission by a single transmission entity on a wireless downlink channel; and

store slot reservations for the synchronous packet transmissions, wherein the stored slot reservations include at least one placeholder slot reservation for at least one slot on the wireless downlink channel that is unscheduled with any synchronous or asynchronous packet transmissions at the time of reservation, wherein the at least one placeholder slot reservation is configured to prohibit scheduling of any asynchronous packet for transmission by the single transmission entity on the wireless downlink channel in the at least one slot for at least a threshold period of time while the at least one slot remains unscheduled with any synchronous or asynchronous packet transmissions,

wherein the stored slot reservations for the synchronous packet transmissions are established irrespective of when synchronous packets to be transmitted are expected to arrive at the single transmission entity for transmission.

34. A method for scheduling synchronous packet transmissions for transmission by a single transmission entity, comprising:

scheduling synchronous packet transmissions for transmission by the single transmission entity; and

storing slot reservations for the synchronous packet transmissions, wherein the stored slot reservations are for at least one slot where any asynchronous packet for transmission by the single transmission entity in the at least one slot is prohibited for at least a threshold period of time irrespective of whether or not the at least one slot is scheduled with any synchronous or asynchronous packet transmissions,

wherein the stored slot reservations for the synchronous packet transmissions correspond to less than all available slots,

and wherein the stored slot reservations for the synchronous packet transmissions are established irrespective of when synchronous packets to be transmitted are expected to arrive at the single transmission entity for transmission.

35. The method of claim 34, further comprising:

receiving one or more asynchronous packets to be scheduled for transmission; and

scheduling the one or more asynchronous packets within one or more unreserved slots that do not conflict with the stored slot reservations.