Tetsu Nakajima

Compressed Block Ack, an efficient selective repeat mechanism for IEEE802.11n

The standardization of IEEE802.11n which aims to achieve 100 Mbps at MAC-SAP (medium access control - service access point) is under work in IEEE802.11, wireless LAN standardization committee. The frame aggregation scheme in which MAC (medium access control) frames are aggregated into one PHY (physical) frame is proposed for IEEE802.11n, because it decreases MAC overhead. In this paper, we propose the compressed block ack mechanism as a selective repeat mechanism to be adapted to the frame aggregation scheme. We present simulation results to compare performance of the compressed block ack mechanism and the legacy block ack of IEEE802.11e and show that the proposed method improves the total throughput by 10% than the conventional method

A Simple and Efficient Selective Repeat Scheme for High Throughput WLAN, IEEE802.11n

The standardization of IEEE802.11n aims to achieve 100 Mbps at MAC-SAP (medium access control - service access point). The frame aggregation scheme in which MAC (medium access control) frames are aggregated into one PHY (physical) frame is proposed as the main MAC technique of IEEE802.11n, because it decreases MAC overhead. The block ack mechanism of IEEE802.11e is applied as a selective repeat method of the frame aggregation. In this paper, we propose the extended block ack mechanism as a selective repeat mechanism to be adapted to the frame aggregation scheme. We present the performance evaluation to compare the throughput of the extended block ack mechanism and the legacy block ack of IEEE802.11e and show that the average improvement is expected to be around 10% and the maximum improvement is about 39% compared with the conventional method.