Optimization of a link adaptation algorithm for voice over wireless LAN applications

Author

Braskich, Tony ; Smavatkul, Nattavut ; Emeott, Steve

Author_Institution

Motorola Labs, Schaumburg, IL, USA

Volume

3

fYear

2005

fDate

13-17 March 2005

Firstpage

1602

Abstract

Auto rate fallback (ARF) is a link adaptation algorithm that uses layer-2 acknowledgement messages to make decisions to increase or decrease the transmission rate. The algorithm is configured by choosing thresholds to define its behavior. The ARF algorithm is applied to voice-over-IP users in an IEEE 802.11a wireless LAN system, and system simulation is used to determine the optimal ARF configuration. Configuration performance is judged using a unique voice quality metric, which is used to establish a measure of system capacity for a single access point with several voice users. Results indicate that the ARF configuration can significantly impact capacity, and one configuration of ARF provides a capacity within 13% of the available capacity.

Keywords

Internet telephony; indoor radio; mobile radio; optimisation; wireless LAN; IEEE 802.11a; WLAN; auto rate fallback; indoor environments; layer-2 acknowledgement messages; link adaptation algorithm optimization; mobile communication; voice over wireless LAN; voice quality metric; voice-over-IP; Battery charge measurement; Discrete event simulation; Indoor environments; Internet telephony; Noise measurement; Physical layer; Signal to noise ratio; Throughput; Wireless LAN;

fLanguage

English

Publisher

ieee

Conference_Titel

Wireless Communications and Networking Conference, 2005 IEEE

ISSN

1525-3511

Print_ISBN

0-7803-8966-2

Type

conf

DOI

10.1109/WCNC.2005.1424753

Filename

1424753