Title : 
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
         
        
        
        
        
        
            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;
         
        
        
        
            Conference_Titel : 
Wireless Communications and Networking Conference, 2005 IEEE
         
        
        
            Print_ISBN : 
0-7803-8966-2
         
        
        
            DOI : 
10.1109/WCNC.2005.1424753