Timer based stall avoidance mechanism for high speed wireless communication system

• US 7,436,795 B2
• Filed: 12/09/2002
• Issued: 10/14/2008
• Est. Priority Date: 01/03/2002
• Status: Active Grant

• Current Assignee: Innovative Sonic Limited
• Original Assignee: Innovative Sonic Limited
• Inventors: Jiang, Sam Shiaw-Shiang
• Primary Examiner(s): Milord; Marceau
• Application Number:
  US10/314,539
• Publication Number:
  US 20030123403A1
• Time in Patent Office: 2,136 Days
• Field of Search: 370/328, 370/394, 370/349, 370/329, 370/389, 370/235, 370/392, 370/278, 370/236, 370/336
• 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 stall of in-sequence delivery of reordering buffers at a 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 being capable of providing priority in-sequence received data blocks delivery by temporarily storing correctly received data blocks based on their priority class and in order of their TSN at reordering buffers before delivering them to upper layers, the method comprising:

at the receiver;

receiving a data block with assigned TSN;

storing a 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 predetermined period of time for a reordering buffer when a received data block (TSN=X) cannot be delivered to an upper layer due to at least one data block with a lower TSN (TSN<

X) in the reordering buffer being missed;

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

X) in the reordering buffer being received; and

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

wherein initializing at least one timer for a reordering buffer is initializing one timer for the reordering buffer and when the timer has expired, removing at least one missing data blocks from the reordering buffer further comprising delivering received data blocks (TSN<

=X-1) of the particular reordering buffer to the upper layer; and

removing all missing data blocks (TSN<

X) from the reordering buffer.

2. The method of claim 1, wherein initializing at least one timer for a reordering buffer is initializing one timer for each missing data block in the reordering buffer and when the timer has 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.

3. The method of claim 2, wherein initializing one timer for each missing data block in 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.

4. The method of claim 1, wherein initializing at least one timer running for a predetermined period of time for a reordering buffer further comprising of the steps of:

receiving a configuration time from the transmitter; and

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

5. A receiver having timer based means for avoiding stall of in-sequence delivery of reordering buffers at a receiver in a high speed downlink packet access (HSDPA) of a wireless communication system, a transmission sequence number (TSN) being assigned to each new data block, the receiver having the capacity of providing priority in-sequence received data blocks delivery by temporarily storing correctly received data blocks based on their priority class and in order of their TSN at the reordering buffers before delivering them to upper layers, and the receiver comprising:

means for receiving a data block with assigned TSN;

means for storing a 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 predetermined period of time for a reordering buffer when a received data block (TSN=X) cannot be delivered to an upper layer due to at least one data block having lower TSN (TSN<

X) in the reordering buffer being missed;

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

X) in the reordering buffer being received; and

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

wherein the means for initializing at least one timer for a reordering buffer is initializing one timer for the reordering buffer and when the timer has expired, the means for removing at least one missing data blocks from the reordering buffer further including means for delivering received data blocks (TSN<

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

means for removing all missing data blocks (TSN<

X) from the reordering buffer.

6. The receiver of claim 5, wherein means for initializing at least one timer for a reordering buffer is means for initializing one timer for each missing data block in the reordering buffer and when the timer has 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.

7. The receiver of claim 6, wherein means for initializing one timer for each missing data block in a 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 has 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.

8. The receiver of claim 5, wherein means for initializing at least one timer running for a predetermined period of time for a reordering buffer further comprising:

means for receiving a configuration time from the transmitter; and

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