A power-efficient MAC protocol for integrated voice and data services over 802.11e HCF

A novel power-efficient MAC protocol, named on-demand polling (ODP) scheme, is presented for supporting integrated voice and data services over WLAN. The ODP scheme combines the polling-based and the contention-based mechanisms over HCF (hybrid coordination function). In the ODP scheme, a voice station is in the polling list when it is in the active mode. During the idle mode, it is configured to operate in the sleep mode for saving power. Also, it adopts the contention-based mechanism to join the list again when returning from the idle mode. In this paper, we investigate the RR-Brady, the RR-CBR and the proposed ODP schemes and derive the power consumption and the aggregate throughput for voice and data stations, respectively. Simulation results show that the ODP scheme can reduce the power consumption for voice stations and enhance the throughput for data stations.