andUser-Level QoSAssessment of Audio-Video Transmission withEDCAofIEEE802.le
Takahiro Suzukit · 2005
Thispaper studies audio-video transmission inawireless LAN withtheEDCAoftheIEEE802.11e MAC protocol intermsofapplica- tion-level QoSanduser-level QoS(i.e., perceptual QoS). Bysimulation, wefirst compare theperformance oftheEDCAandthelegacy IEEE802.11 DCFinthecasewhereaudio, video, anddataaretransmitted inacom- monwireless channel. TheEDCAsupports priority control formultime- diatransmission. Numerical results showthat theEDCAcanimprove the audio andvideo quality oftheDCFwhendatatraffic loadisheavy. We thenstudy theeffects ofdynamic video-resolution andmediasynchroni- zation control ontheapplication-level QoS. Simulation results showthat thetwokinds ofcontrol attheapplication layer inaddition topriority control with theEDCAattheMAClayer iseffective inachieving excellent application-level QoSofaudio-video transmission. Furthermore, weas- sess user-level QoSbythemethod ofsuccessive categories, whichisoneof thepsychometric methods. I.INTRODUCTION