Block-Poll Coordination Function for Improving Throughput Performance in Wireless Lans

IEEE 802.11 DCF shows the inefficient throughput performance, due to the large backoff and collision overheads. We propose the Block-poll coordination function (BCF) to reduce the back-off and collision overheads, thus increasing the aggregate throughput. By introducing a new Block-poll frame which includes a polling bitmap, each station can decide its transmission order, so that the channel access emulates TDMA. In addition, by dividing the polling bitmap into several chunks and transmitting only the changed chunks, the polling overhead can be reduced. The simulation and analysis results show the proposed protocol achieves higher throughput than IEEE 802.11 DCF, while reducing the average delay and the delay jitter values.