Method and apparatus for assigning scheduling for uplink packet transmission in a mobile communication system

• US 20050078651A1
• Filed: 08/16/2004
• Published: 04/14/2005
• Est. Priority Date: 08/16/2003
• Status: Abandoned Application

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Choi, Sung-Ho, Heo, Youn-Hyoung, Kim, Young-Bum, Kwak, Yong-Jun, Lee, Ju-Ho
• Application Number:
  US10/919,036
• Publication Number:
  US 20050078651A1
• Time in Patent Office: Days
• US Class Current: 370/349
• CPC Class Codes: H04L 47/10 Flow control; Congestion control
• CPC Class Codes: H04L 47/263 Rate modification at the source after receiving feedback
• CPC Class Codes: H04L 47/29 using a combination of thresholds
• CPC Class Codes: H04L 47/30 in combination with information about buffer occupancy at either end or at transit nodes
• CPC Class Codes: H04W 28/02 Traffic management, e.g. flow control or congestion control
• CPC Class Codes: H04W 28/14 using intermediate storage
• CPC Class Codes: H04W 52/14 Separate analysis of uplink or downlink
• CPC Class Codes: H04W 52/286 during data packet transmission, e.g. high speed packet access [HSPA]
• CPC Class Codes: H04W 52/362 Aspects of the step size
• CPC Class Codes: H04W 52/40 during macro-diversity or soft handoff
• CPC Class Codes: H04W 72/21 in the uplink direction of a wireless link, i.e. towards the network
• CPC Class Codes: H04W 72/52 based on load
• CPC Class Codes: H04W 72/542 using measured or perceived quality
• CPC Class Codes: H04W 8/04 Registration at HLR or HSS [Home Subscriber Server]

Abstract

A method in a UE of transmitting buffer state information and CSI for scheduling an uplink packet data service in a mobile communication system supporting the uplink packet data service is provided. The buffer state information indicates a state of a data buffer for storing packet data to be transmitted from the UE and the CSI indicates an uplink transmit power of the UE. The UE acquires different transmission intervals of the buffer state information and the CSI, initially transmits the buffer state information and the CSI, if the amount of packet data stored in the buffer is equal to or greater than a predetermined threshold, and periodically transmits the buffer state information and the CSI at the transmission intervals.

Claims

1. A method in a user equipment (UE) for transmitting buffer state information and channel state information (CSI) for scheduling an uplink packet data service in a mobile communication system supporting the uplink packet data service, the buffer state information indicating a state of a data buffer for storing packet data to be transmitted from the UE and the CSI indicating an uplink transmit power of the UE, the method comprising the steps of:

acquiring different transmission intervals of the buffer state information and the CSI;

initially transmitting the buffer state information and the CSI, if an amount of packet data stored in the data buffer is at least equal to a predetermined threshold; and

periodically transmitting the buffer state information and the CSI at the different transmission intervals.

2. The method of claim 1, further comprising the step of attaching the buffer state information to a cyclic redundancy code (CRC) for transmission error detection, before the initially transmitting and the periodically transmitting steps.

3. The method of claim 1, wherein the buffer state information and the CSI are initially transmitted and periodically transmitted in assigned areas of a predetermined scheduling interval, and the transmission intervals of the buffer state information and the CSI are integer multiples of a duration of the predetermined scheduling interval.

4. The method of claim 3, wherein the buffer state information and the CSI are periodically transmitted in the assigned areas of scheduling intervals from an initial transmission time, by integer multiples of the predetermined transmission intervals.

5. The method of claim 3, wherein the buffer state information and the CSI are periodically transmitted in the assigned areas of scheduling intervals from predetermined reference scheduling intervals for the buffer state information and the CSI, after an initial transmission time, by integer multiples of the predetermined transmission intervals.

6. The method of claim 5, wherein each of the reference scheduling intervals is determined by

(CNT_sch—

_int−

offset)mod(T/T<sub>sch—

int</sub>)=0

where CNT<sub>sch—

int</sub> is an index of the reference scheduling interval, offset is an integer value as different as possible for each UE, mod is an operator that computes a remainder of a division between two operands, T is a transmission interval of the buffer state information or the CSI, and T<sub>sch—

int</sub> is a duration of the scheduling interval.

7. The method of claim 1, further comprising the step of discontinuing the periodic transmission of the buffer state information and the CSI, if the amount of the packet data stored in the data buffer is less than the predetermined threshold.

8. The method of claim 1, further comprising the step of discontinuing the periodic transmission of the buffer state information and the CSI, upon receiving a scheduling release message requesting termination of the transmission of the buffer state information and the CSI.

9. The method of claim 1, wherein a transmission interval of the buffer state information is longer than a CSI transmission interval.

10. The method of claim 1, wherein when the UE communicates with at least two Node Bs in a soft handover, a transmission interval of the buffer state information is longer than a CSI transmission interval.

11. The method of claim 1, wherein a transmission interval of the buffer state information is shorter than a CSI transmission interval.

12. The method of claim 1, wherein when the CSI reflects an uplink channel state change over a term that is long enough to overcome long-term fading, a transmission interval of the buffer state information is shorter than a CSI transmission interval.

13. The method of claim 1, wherein the different transmission intervals of the buffer state information and the CSI are determined according to a quality of service (QoS) requirement for the uplink packet data service and radio resources available to receive the uplink packet data service.

14. A method in a Node B for receiving buffer state information and channel state information (CSI) from a user equipment (UE) for scheduling an uplink packet data service in a mobile communication system supporting the uplink packet data service, comprising the steps of:

acquiring different reception intervals of the buffer state information and the CSI;

determining if the buffer state information and the CSI have been initially received; and

periodically receiving the buffer state information and the CSI at the different reception intervals, if the buffer state information and the CSI have been initially received.

15. The method of claim 14, wherein the step of determining if the buffer state information and the CSI have been initially received, comprises the steps of:

acquiring received data including the buffer state information and a cyclic redundancy code (CRC) of the received data for transmission error detection; and

receiving the buffer state information and the CSI, if the received data has no error by a CRC check.

16. The method of claim 14, wherein the buffer state information and the CSI are initially and periodically received in assigned areas of a predetermined scheduling interval, and the different reception intervals of the buffer state information and the CSI are integer multiples of a duration of the predetermined scheduling interval.

17. The method of claim 16, the buffer state information and the CSI are periodically received in the assigned areas of scheduling intervals from an initial reception time, by integer multiples of the different reception intervals.

18. The method of claim 16, wherein the buffer state information and the CSI are periodically received in the assigned areas of scheduling intervals from predetermined reference scheduling intervals for the buffer state information and the CSI, after an initial reception time, by integer multiples of the different reception intervals.

19. The method of claim 18, wherein each of the reference scheduling intervals is determined by

(CNT_sch—

_int−

offset )mod(T/T<sub>sch—

int</sub>)=0

where CNT<sub>sch—

int</sub> it is an index of the reference scheduling interval, offset is an integer as different as possible for each UE, mod is an operator that computes a remainder of a division between two operands, T is a reception interval of the buffer state information or the CSI, and T<sub>sch—

int</sub> is a duration of the scheduling interval.

20. The method of claim 14, further comprising the steps of:

estimating the buffer state of the UE by calculating a difference between previous buffer state information and an amount of packet data received after the previous buffer state information; and

discontinuing the periodic reception of the buffer state information and the CSI, if the buffer state estimate is less than a predetermined threshold.

21. The method of claim 20, further comprising the step of transmitting to the UE a scheduling release message requesting termination of the transmission of the buffer state information and the CSI.

22. The method of claim 14, wherein a reception interval of the buffer state information is longer than a CSI reception interval.

23. The method of claim 14, wherein when the UE communicates with at least two Node Bs in a soft handover, a reception interval of the buffer state information is longer than a CSI reception interval.

24. The method of claim 14, wherein a reception interval of the buffer state information is shorter than a CSI reception interval.

25. The method of claim 14, wherein when the CSI reflects an uplink channel state change over a long term enough to overcome long-term fading, a reception interval of the buffer state information is shorter than a CSI reception interval.

26. The method of claim 14, wherein the different reception intervals of the buffer state information and the CSI are determined according to a quality of service (QoS) requirement for the uplink packet data service and radio resources available to the Node B for the uplink packet data service.

27. A transmitter in a user equipment (UE) for transmitting buffer state information and channel state information (CSI) for scheduling an uplink packet data service in a mobile cornmunication system supporting the uplink packet data service, the buffer state information indicating a state of a data buffer for storing packet data to be transmitted from the UE and the CSI indicating an uplink transmit power of the UE, the transmitter comprising:

a transmission start and end decider for determining a transmission start and end of the buffer state information and the CSI by comparing an amount of packet data stored in the data buffer with a predetermined threshold, the transmission start being determined as a time when the data amount is at least equal to the predetermined threshold; and

a transmission time decider for acquiring different transmission intervals of the buffer state information and the CSI, and determining different transmission times for the buffer state information and the CSI according to the acquired transmission intervals, wherein the transmission start is used as a reference time;

a buffer state transmitter for periodically transmitting the buffer state information at the buffer state transmission times; and

a CSI transmitter for periodically transmitting the CSI at the CSI transmission times.

28. The transmitter of claim 27, wherein the buffer state transmitter comprises:

a switch for receiving the buffer state information at each of the buffer state transmission time;

a cyclic redundancy code (CRC) adder for attaching a CRC to the buffer state information in order to detect transmission errors from the buffer station information; and

a channel encoder for channel-encoding the CRC-attached buffer state information and transmitting the channel-encoded buffer state information.

29. The transmitter of claim 27, wherein the CSI transmitter comprises:

a switch for receiving the CSI at each of the CSI transmission times; and

a channel encoder for channel-encoding the CSI and transmitting the channel-encoded CSI.

30. The transmitter of claim 27, wherein the buffer state transmitter and the CSI transmitter transmit the buffer state information and the CSI in assigned areas of a predetermined scheduling interval, and the different transmission intervals of the buffer state information and the CSI are integer multiples of a duration of the scheduling interval.

31. The transmitter of claim 30, wherein the buffer state transmitter and the CSI transmitter transmit the buffer state information and the CSI in the assigned areas of scheduling intervals from the reference time point, by integer multiples of the different transmission intervals.

32. The transmitter of claim 30, wherein the buffer state transmitter and the CSI transmitter transmit the buffer state information and the CSI in the assigned areas of scheduling intervals from predetermined reference scheduling intervals for the buffer state information and the CSI, after the reference time, by integer multiples of the different transmission intervals.

33. The transmitter of claim 32, wherein each of the reference scheduling intervals is determined by

(CNT_sch—

_int−

offset)mod(T/T<sub>sch—

int</sub>)=0

where CNT<sub>sch—

int</sub> is an index of the reference scheduling interval, offset is an integer as different as possible for each UE, mod is an operator that computes a remainder of a division between two operands, T is a transmission interval of the buffer state information or the CSI, and T<sub>sch—

int</sub> is a duration of the scheduling interval.

34. The transmitter of claim 27, wherein the transmission time decider determines the transmission end as a time when the amount of the packet data stored in the data buffer is less than the threshold.

35. The transmitter of claim 27, wherein the transmission time decider determines the transmission end as a time when a scheduling release message is received from the Node B, after the transmission state time point, and the scheduling release message requests termination of the transmission of the buffer state information and the CSI.

36. The transmitter of claim 27, wherein a transmission interval of the buffer state information is longer than a CSI transmission interval.

37. The transmitter of claim 27, wherein when the UE communicates with at least two Node Bs in a soft handover, a transmission interval of the buffer state information is longer than a CSI transmission interval.

38. The transmitter of claim 27, wherein a transmission interval of the buffer state information is shorter than a CSI transmission interval.

39. The transmitter of claim 27, wherein when the CSI reflects an uplink channel state change over a term that is long enough to overcome long-term fading, a transmission interval of the buffer state information is shorter than a CSI transmission interval.

40. The transmitter of claim 27, wherein the different transmission intervals of the buffer state information and the CSI are determined according to a quality of service (QoS) requirement for the uplink packet data service and radio resources available to receive the uplink packet data service.

41. A receiver in a Node B for receiving buffer state information and channel state information (CSI) from a user equipment (UE) for scheduling an uplink packet data service in a mobile communication system supporting the uplink packet data service, comprising:

a reception time decider for acquiring different reception intervals of the buffer state information and the CSI, and determining reception times for the buffer state information and the CSI according to the different reception intervals using a reception start time of the buffer state information and the CSI as a reference time point;

a buffer state receiver for determining if the buffer state information has been initially received from the UE, identifying a time when the buffer state information has been initially received as the reception start time point, and periodically receiving the buffer state information at the determined buffer state reception times; and

a CSI receiver for periodically receiving the CSI at the determined CSI reception times.

42. The receiver of claim 41, wherein the buffer state receiver comprises:

a switch for acquiring received data including the buffer state information and a cyclic redundancy code (CRC) of the received data for transmission error detection, continuously receiving the received data before the reception start time point, and receiving the received data at the determined buffer state reception times after the reception start time point; and

a CRC checker for detecting the buffer state information from the received data, if the received data has no error by a CRC check.

43. The receiver of claim 41, wherein the CSI receiver comprises:

a switch for acquiring received data including the CSI at the determined CSI reception times; and

a channel decoder for decoding the received data and detecting the CSI from the decoded data.

44. The receiver of claim 41, wherein the buffer state receiver and the CSI receiver receive the buffer state information and the CSI in assigned areas of a predetermined scheduling interval, and the different reception intervals of the buffer state information and the CSI are integer multiples of a duration of the predetermined scheduling interval.

45. The receiver of claim 44, wherein the buffer state receiver and the CSI receiver receive the buffer state information and the CSI in the assigned areas of scheduling intervals from the reference time, by integer multiples of the different reception intervals.

46. The receiver of claim 44, wherein the buffer state receiver and the CSI receiver receive the buffer state information and the CSI in the assigned areas of scheduling intervals from predetermined reference scheduling intervals for the buffer state information and the CSI, after the reference time, by integer multiples of the different reception intervals.

47. The receiver of claim 46, wherein each of the reference scheduling intervals is determined by

(CNT_sch—

_int−

offset )mod(T/T<sub>sch—

int</sub>)=0

where CNT<sub>sch—

int</sub> is an index of the reference scheduling interval, offset is an integer as different as possible for each UE, mod is an operator that computes a remainder of a division between two operands, T is a reception interval of the buffer state information or the CSI, and T<sub>sch—

int</sub> is a duration of the scheduling interval.

48. The receiver of claim 41, wherein the reception time decider estimates the buffer state of the UE by calculating a difference between previous buffer state information and an amount of packet data received after the previous buffer state information, and determines a reception end time as a time when the buffer state estimate is less than a predetermined threshold.

49. The receiver of claim 48, wherein the reception time decider controls a scheduling release message to be transmitted to the UE at the reception end time, and the scheduling release message requests termination of the transmission of the buffer state information and the CSI.

50. The receiver of claim 41, wherein a reception interval of the buffer state information is longer than a CSI reception interval.

51. The receiver of claim 41, wherein when the UE communicates with at least two Node Bs in a soft handover, a reception interval of the buffer state information is longer than a CSI reception interval.

52. The receiver of claim 41, wherein a reception interval of the buffer state information is shorter than a CSI reception interval.

53. The receiver of claim 41, wherein when the CSI reflects an uplink channel state change over a term that is long enough to overcome long-term fading, a reception interval of the buffer state information is shorter than a CSI reception interval.

54. The receiver of claim 41, wherein the different reception intervals of the buffer state information and the CSI are determined according to a quality of service (QoS) requirement for the uplink packet data service and radio resources available to the Node B for the uplink packet data service.