Methodology for improving the performance of asynchronous data traffic over TDD/TDMA wireless networks

• US 6,963,534 B1
• Filed: 10/05/2000
• Issued: 11/08/2005
• Est. Priority Date: 10/05/2000
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Razdan, Ashu, Saran, Huzur, Ghose, Abhishek, Das, Abhishek, Shorey, Rajeev
• Primary Examiner(s): Hsu, Alpus H.
• Assistant Examiner(s): Ryman, Daniel J.
• Application Number:
  US09/680,168
• Time in Patent Office: 1,860 Days
• Field of Search: 370/230, 370/337, 370/345, 370/346, 370/347, 370/449, 370/468, 370/470, 370/471, 370/474, 370/349, 370/395.1, 370/395.4, 370/412, 370/428, 370/429, 370465-467, 455/450, 455/452.1, 455/453
• US Class Current: 370/230
• CPC Class Codes: H04J 3/1682 Allocation of channels according to the instantaneous demands of the users, e.g. concentrated multiplexers, statistical multiplexers
• CPC Class Codes: H04J 3/247 ATM or packet multiplexing
• CPC Class Codes: H04W 28/06 Optimizing the usage of the radio link, e.g. header compression, information sizing , discarding information system modifying transmission characteristic according to link quality by modifying frame length H04L1/0007; dynamic adaptation of the packet size for flow control or congestion control H04L47/365
• CPC Class Codes: H04W 28/14 using intermediate storage
• CPC Class Codes: H04W 74/00 Wireless channel access
• CPC Class Codes: H04W 74/04 Scheduled access hybrid access H04W74/02

Abstract

The present invention relates to a computer implemented system for transferring data over a master driven TDD/TDMA based wireless network operating with minimum delay in end-to-end transmission by achieving optimum time slot utilization by minimizing the number of baseband packets created for each Link layer packet, where each baseband packet of is a size corresponding to one of a permitted set of capacities ‘C₁, C₂, . . . Cn’. The system also optimizes sharing of bandwidth, higher link utilization and low baseband packet transmission queue occupancy by adaptive scheduling of the transmission of the baseband packets in the queues. The invention also provides a method and computer program product for the above system.

Claims

1. A computer implemented system for transferring data over a master driven TDD/TDMA based wireless network characterized in that it operates with minimum delay in end-to-end transmission by including:

means for achieving optimum time slot utilization by minimizing the number of baseband packets created for each Link layer packet, each baseband packet being of a size corresponding to one of a permitted set of capacities ‘

C1, C2, . . . Cn’

, wherein minimizing the number of baseband packets created for said each Link layer packet comprises converting said Link layer packet into as many baseband packets of highest capacity ‘

Cn’

as possible and repeating a conversion process or unconverted bytes using each successive lower capacity baseband packet size until all the unconverted bytes have been converted into said baseband packets; and

means for optimum sharing of bandwidth, higher link utilization and low baseband packet transmission queue occupancy by adaptive scheduling of the transmission of said baseband packets in said queues.

2. A system as claimed in claim 1, wherein said means for minimizing the number of baseband packets created for said each Link layer packet is an Segmentation and Reassembly Optimum Slot Utilization (SAR-OSU) algorithm.

3. A system as claimed in claim 1, wherein said master driven TDD/TDMA based wireless network comprises a Bluetooth network and said Link layer packet comprises a Logical Link Control and Adaptation Protocol (L2CAP) packet.

4. A system as claimed in claim 1, wherein said means for adaptive scheduling of transmission is an Adaptive Flow-based Polling (AFP) algorithm whereby a baseband packet transmission queue with a size greater than a defined threshold is continuously polled for a defined number of transmissions as long as its size remains greater than said defined threshold.

5. A system as claimed in claim 1 further comprising means for increasing the transmission polling interval for a baseband packet transmission queue with low packet traffic when a ‘

poll’

packet is sent instead of a ‘

data’

packet.

6. A computer implemented method for transferring data over a master driven TDD/TDMA based wireless network characterized in that it operates with minimum delay in end-to-end transmission by:

achieving optimum time slot utilization by minimizing the number of baseband packets created for each Link Layer packet, each baseband packet being of a size corresponding to one of a permitted set of capacities ‘

C1, C2, . . . Cn’

, wherein minimizing the number of baseband packets created for said each Link layer packet comprises converting said Link layer packet into as many baseband packets of highest capacity ‘

Cn’

as possible and repeating a conversion process on unconverted bytes using each successive lower capacity baseband packet size until all the unconverted bytes have been converted into said baseband packets; and

maintaining optimum sharing of bandwidth, higher link utilization and low baseband packet transmission queue occupancy by adaptive scheduling of the transmission of said baseband packets in said queues.

7. A method as claimed in claim 6, wherein said minimizing the number of said baseband packets created for said each Link layer packet is by an Segmentation and Reassembly Optimum Slot Utilization (SAR-OSU) algorithm.

8. A method as claimed in claim 6, wherein said master driven TDD/TDMA based wireless network comprises a Bluetooth network and said Link layer packet comprises a Logical Link Control and Adaptation Protocol (L2CAP) packet.

9. A method as claimed in claim 6, wherein said adaptive scheduling of transmission is by an Adaptive Flow-based Polling (AFP) algorithm whereby a queue with a size greater than a defined threshold is continuously polled for a defined number of transmissions as long as its size remains greater than said defined threshold.

10. A method as claimed in claim 6 further comprising increasing the transmission polling interval for a baseband packet transmission queue with low packet traffic when a ‘

poll’

packet is sent instead of a ‘

data’

packet.

11. A computer program product comprising computer readable program code stored on computer readable storage medium embodied therein for causing a computer to transfer data over a master driven TDD/TDMA based wireless network characterized in that it operates with minimum delay in end-to-end transmission by including:

a computer readable program code adapted to achieving optimum time slot utilization by minimizing the number of baseband packets created for each Link layer packet, each baseband packet being of a size corresponding to one of a permitted set of capacities ‘

C1, C2, . . . Cn’

, wherein minimizing the number of baseband packets created for said each Link layer packet comprises converting said Link layer packet into as many baseband packets of highest capacity ‘

Cn’

as possible and repeating a conversion process on unconverted bytes using each successive lower capacity baseband packet size until all the unconverted bytes have been converted into said baseband packets; and

a computer readable program code adapted to implementing optimum sharing of bandwidth, higher link utilization and low baseband packet queue occupancy by adaptive scheduling of the transmission of said baseband packets in said queues.

12. A computer program product as claimed in claim 11, wherein said computer readable program code adapted to minimizing the number of baseband packets created for said each Link layer packet is an Segmentation and Reassembly Optimum Slot Utilization (SAR-OSU) algorithm.

13. A computer program product as claimed in claim 11, wherein said master driven TDD/TDMA based wireless network comprises a Bluetooth network, and said Link layer packet comprises a Logical Link Control and Adaptation Protocol (L2CAP) packet.

14. A computer program product as claimed in claim 11, wherein said computer readable program code adapted to adaptive scheduling for transmission comprises an Adaptive Flow-based Polling (AFP) algorithm whereby a queue with a size greater than a defined threshold is continuously polled for a defined number of transmissions as long as its size remains greater than the defined threshold.

15. A computer program product as claimed in claim 11 further comprising a computer readable program code adapted to increasing the transmission polling interval for a baseband packet transmission queue with low packet traffic when a ‘

poll’

packet is sent instead of a ‘

data’

packet.