Throughput enhancement of IEEE 802.11 WLAN via frame aggregation

The popular IEEE 802.11 WLAN is known to achieve relatively small throughput performance compared to the underlying physical layer (PHY) transmission rate. This is due mainly to the large overheads composed of medium access control (MAC) header, PHY preamble/header, backoff time, acknowledgement (ACK) transmission, and some inter-frame spaces (IFSs). Since these overheads are added to each frame transmission, the throughput degradation is relatively high with small-size frames. In this paper, we present a frame aggregation (FA) scheme, which can improve the throughput performance. By aggregating small-size frames into a large frame, we can reduce these overheads relatively. We propose a simple method to implement the FA into the real testbed using off-the-shelf products via device driver modifications. The performance of the FA is evaluated by both numerical analysis and actual measurements from the real testbed. According to the measurement results, the FA can improve the throughput performance by 2 to 3 Mbps, when multiple frames are aggregated.