Timer based stall avoidance mechanism for high speed wireless communication system

• US 20030123403A1
• Filed: 12/09/2002
• Published: 07/03/2003
• Est. Priority Date: 01/03/2002
• Status: Active Grant

• Current Assignee: Innovative Sonic Limited
• Original Assignee: Innovative Sonic Limited
• Inventors: Jiang, Sam Shiaw-Shiang
• Granted Patent: US 7,436,795 B2
• Time in Patent Office: Days
• US Class Current: 370/328
• CPC Class Codes: H04L 1/1812 Hybrid protocols; Hybrid automatic repeat request [HARQ]
• CPC Class Codes: H04L 1/1841 Resequencing
• CPC Class Codes: H04L 1/1848 Time-out mechanisms
• CPC Class Codes: H04L 1/1851 using multiple timers
• CPC Class Codes: H04L 1/1883 using multiple timers
• CPC Class Codes: H04L 47/10 Flow control; Congestion control
• CPC Class Codes: H04L 47/28 in relation to timing considerations
• CPC Class Codes: H04L 69/28 Timers or timing mechanisms used in protocols

Abstract

This invention uses timers at the transmitter to track its sending data blocks to improve the timer-based stall avoidance mechanism of the prior art. Moreover, the invention uses a multi-timer mechanism to manage reordering buffers at the receiver. The multi-timer mechanism provides the receiver with one timer per reorder buffer, or uses one timer per missing data block, or uses one timer per missing data block but a gap of consecutive TSN missing data blocks can share one timer. The multi-timer mechanism can effectively track the missing blocks and monitor the reorder delivery process for all reordering buffers.

Claims

1. A timer based method to avoid the stall of in-sequence delivery of the reordering buffers at the receiver in a High Speed Downlink Packet Access (HSDPA) of a wireless communication system, where the transmitter assigning a Transmission Sequence Number (TSN) to the new sending data blocks, wherein the method comprising the steps of:

at the transmitter;

starting a timer to run for a first predetermined period of time when sending a data block having a new TSN;

stopping the timer if received a positive acknowledgment responding to the sent data block before the timer expires; and

if the timer expired, removing the particular data block from the retransmission buffer.

2. The method as claimed in claim 1, wherein starting a timer to run for a first predetermined period of time further comprising the steps of:

setting a configuration time that is equal to or greater than the first predetermined period of time; and

sending the configuration time to a receiver.

3. A timer based method to avoid the stall of in-sequence delivery of the reordering buffers at the receiver in a High Speed Downlink Packet Access (HSDPA) of a wireless communication system, where a Transmission Sequence Number (TSN) is assigned to each new data blocks, while the receiver having the capacity of providing priority in-sequence received data blocks delivery by temporarily storing the correctly received data blocks based on their priority class and in the order of their TSN at reordering buffers before delivering them to upper layers, wherein the method comprising the steps of:

at the receiver;

receiving the data block with assigned TSN;

storing the correctly received data block into one of the reordering buffers based on the data block'"'"'s priority class and the order of its TSN;

initializing at least one timer running for a second predetermined period of time for each reordering buffer when a received data block (TSN=X) can'"'"'t be delivered to upper layer due to at least one data block with lower TSN (TSN<

X) in the reordering buffer is missed;

stopping the timer if the data block (TSN=X) can be delivered to upper layer due to all the data blocks with lower TSN (TSN<

X) in the reordering buffer is received; and

when the timer expired, removing at least one missing data block from the reordering buffer.

4. The method as claimed in claim 3, wherein initializing at least one timer for each reordering buffer is initializing one timer per reordering buffer and when the timer expired, removing missing data blocks from the reordering buffer further comprising of delivering received data blocks (TSN<

=X−

1) of the particular reordering buffer to upper layers; and

removing all missing data blocks (TSN<

X) from the reordering buffer.

5. The method as claimed in claim 3, wherein initializing at least one timer for each reordering buffer is initializing one timer for each missing data block in the reordering buffer and when the timer expired, removing at least one missing data blocks from the reordering buffer further comprising of removing the timer-monitored missing data block from the reordering buffer.

6. The method as claimed in claim 5, wherein initializing one timer for each missing data block in each reordering buffer further comprising of using one timer to monitor a missing gap having a plurality of missing data blocks with consecutive TSNs, while the missing data blocks are not removed from the reordering buffer, no other timer will be assigned to any missing data blocks within the missing gap;

and when the timer expired, removing at least one missing data blocks from the reordering buffer is to remove the timer-monitored missing data block(s) from the reordering buffer.

7. The method as claimed in claim 3, wherein initializing at least one timer running for a second predetermined period of time for each reordering buffer further comprising of the steps of:

receiving a configuration time from the transmitter; and

setting the second predetermined period of time equal or greater than the received configuration time.

8. A transmitter having timer based means for avoiding the stall of in-sequence delivery of the reordering buffers at the receiver in a High Speed Downlink Packet Access (HSDPA) of a wireless communication system, where the transmitter assigning a Transmission Sequence Number (TSN) to the new sending data blocks, wherein the transmitter comprising:

means for starting a timer to run for a first predetermined period of time when sending a data block having a new TSN;

means for stopping the timer if received a positive acknowledgment responding to the sent data block before the timer expires; and

if the timer expired, means for removing the particular data block from the retransmission buffer.

9. The transmitter as claimed in claim 8, wherein means for starting a timer to run for a first predetermined period of time further comprising:

means for setting a configuration time that is equal to or greater than the first predetermined period of time; and

means for sending the configuration time to a receiver.

10. A receiver having timer based means for avoiding the stall of in-sequence delivery of the reordering buffers at the receiver in a High Speed Downlink Packet Access (HSDPA) of a wireless communication system, where a Transmission Sequence Number (TSN) is assigned to each new data blocks, while the receiver having the capacity of providing priority in-sequence received data blocks delivery by temporarily storing the correctly received data blocks based on their priority class and in the order of their TSN at reordering buffers before delivering them to upper layers, wherein the receiver comprising:

means for receiving the data block with assigned TSN;

means for storing the correctly received data block into one of the reordering buffers based on the data block'"'"'s priority class and the order of its TSN;

means for initializing at least one timer running for a second predetermined period of time for each reordering buffer when a received data block (TSN=X) can'"'"'t be delivered to upper layer due to at least one data block with lower TSN (TSN<

X) in the reordering buffer is missed;

means for stopping the timer if the data block (TSN=X) can be delivered to upper layer due to all the data blocks with lower TSN (TSN<

X) in the reordering buffer is received; and

when the timer expired, means for removing at least one missing data block from the reordering buffer.

11. The receiver as claimed in claim 10, wherein means for initializing at least one timer for each reordering buffer is initializing one timer per reordering buffer and when the timer expired, means for removing missing data blocks from the reordering buffer further comprising means for delivering received data blocks (TSN<

=X−

1) of the particular reordering buffer to upper layers; and

means for removing all missing data blocks (TSN<

X) from the reordering buffer.

12. The receiver as claimed in claim 10, wherein means for initializing at least one timer for each reordering buffer is initializing one timer for each missing data block in the reordering buffer and when the timer expired, means for removing at least one missing data blocks from the reordering buffer further comprising means for removing the timer-monitored missing data block from the reordering buffer.

13. The receiver as claimed in claim 12, wherein means for initializing one timer for each missing data block in each reordering buffer further comprising means for using one timer to monitor a missing gap having a plurality of missing data blocks with consecutive TSNs, while the missing data blocks are not removed from the reordering buffer, no other timer will be assigned to any missing data blocks within the missing gap;

and when the timer expired, means for removing at least one missing data blocks from the reordering buffer further comprising means for removing the timer-monitored missing data block(s) from the reordering buffer.

14. The receiver as claimed in claim 10, wherein means for initializing at least one timer running for a second predetermined period of time for each reordering buffer further comprising:

means for receiving a configuration time from the transmitter; and

means for setting the second predetermined period of time equal or greater than the received configuration time.