Method and system for integrated link adaptation and power control to improve error and throughput performance in wireless packet networks

• US 7,502,340 B1
• Filed: 05/12/2000
• Issued: 03/10/2009
• Est. Priority Date: 05/12/2000
• Status: Expired due to Fees

• Current Assignee: AT&T Corporation (AT&T, Inc.)
• Original Assignee: AT&T Corporation (AT&T, Inc.)
• Inventors: Leung, Kin K, Wang, Li-Chun, Chuang, Justin Che-I
• Primary Examiner(s): PATEL, AJIT
• Application Number:
  US09/570,097
• Time in Patent Office: 3,224 Days
• Field of Search: 370/311, 370/318, 370/332, 370/333, 370/335, 370/328, 455/450, 455/452, 455/13.4, 455/574, 455/522
• US Class Current: 370/318
• CPC Class Codes: H04L 1/0003 by switching between different modulation schemes
• CPC Class Codes: H04L 1/0015 characterised by the adaptation strategy
• CPC Class Codes: H04L 1/0019 in which mode-switching is based on a statistical approach
• CPC Class Codes: H04L 27/0008 arrangements for allowing a transmitter or receiver to use more than one type of modulation negotiating modulation type for two-way transmission paths H04L5/1453
• CPC Class Codes: H04W 24/02 Arrangements for optimising operational condition
• CPC Class Codes: H04W 28/04 Error control
• CPC Class Codes: H04W 28/18 Negotiating wireless communication parameters
• CPC Class Codes: H04W 4/08 User group management
• CPC Class Codes: H04W 52/20 using error rate

Abstract

The invention provides a system that implements an algorithm for integrated link adaptation and power control to achieve specified error rates and to improve an overall throughput for real-time applications in wireless packet networks. The system initially divides wireless terminals into groups according to their signal path gains. Afterwards, the system can periodically adapt transmissions (i.e., link adaptations) based on the required error rates, actual error statistics and average transmission power for each wireless terminal group. Furthermore, transmission power can be adjusted by an enhanced Kalman-filter method to ensure successful reception.

Claims

1. A method for improving error performance and throughput performance of a wireless network, comprising:

dividing a plurality of wireless terminals into a plurality of groups, at least one of the groups including two or more wireless terminals; and

adapting a modulation level for each of the groups

wherein dividing the plurality of wireless terminals into a plurality of groups is based on a signal path gain corresponding to each of the wireless terminals.

2. A method for improving error performance and throughput performance of a wireless network, comprising:

dividing a plurality of wireless terminals into a plurality of groups, at least one of the groups including two or more wireless terminals; and

adapting a modulation level for each of the groups;

wherein adapting a modulation level for each of the groups is based on a transmission power statistic, and wherein

wherein the transmission power statistic is an average power over a predetermined number of packets transmitted to the groups.

3. A method for improving error performance and throughput performance of a wireless network, comprising:

dividing a plurality of wireless terminals into a plurality of groups, at least one of the groups including two or more wireless terminals; and

adapting a modulation level for each of the groups;

wherein adapting a modulation level for each of the groups is based on a transmission power statistic, wherein the transmission power statistic its an average power over a predetermined number of packets received by the groups.

4. An apparatus for improving error performance and throughput performance of a wireless network comprising:

a controller that divides a plurality of wireless terminals into a plurality of groups, at least one of the groups including two or more wireless terminals, and that adapts a modulation level for each of the groups;

wherein dividing the plurality of wireless terminals into a plurality of groups is based on a signal path gain corresponding to each of the wireless terminals.

5. An apparatus for improving error performance and throughput performance of a wireless network, comprising:

a controller that divides a plurality of wireless terminals into a plurality of groups, at least one of the groups including two or more wireless terminals, and that adapts a modulation level for each of the groups;

wherein adapting a modulation level for each of the groups is based on a transmission power statistic, wherein the transmission power statistic is an average power over a predetermined number of packets transmitted to the groups.

6. An apparatus for improving error performance and throughput performance of a wireless network, comprising:

a controller that divides a plurality of wireless terminals into a plurality of groups, at least one of the groups including two or more wireless terminals, and that adapts a modulation level for each of the groups;

wherein adapting a modulation level for each of the groups is based on a transmission power statistic, wherein the transmission power statistic is an average power over a predetermined number of packets received by the groups.