Adaptive Interactive Speech Transmission Over 802.11 Wireless LAN
Antonio Servetti, Juan Carlos De Martin · PORTO Publications Open Repository TOrino (Politecnico di Torino) · 2003
We present an adaptive technique to transmit speech over 802.11 wireless packet networks. According to the proposed scheme, the speech coding rate of a network-driven variable bitrate coder is selected to match the istantaneous wireless channel conditions: higher rates (i.e., larger packets) for low error rates, lower rates (i.e., smaller packets) when the channel is noisy. Packet size is, in fact, directly related to the probability of retransmission, one of the major sources of delay in contention-based medium access control. Network simulation results show that the adaptive approach can address the stringent quality of service requirements for two way interactive speech applications over wireless packet networks, reducing packet loss rates and end-to-end delays.