Date Added: May 2011
Low packet delay and packet loss probability are the two most contradicting requirements of Wireless Sensor and Actuator Networks (WSAN). In this paper, saturation delay characteristics of Multiple Input Multiple Output (MIMO)-enabled IEEE 802.11 technology utilizing Enhanced Distributed Channel Access (EDCA) at Medium Access Control (MAC) and a simple spatial-multiplexing scheme in PHYsical (PHY) layer has been thoroughly analyzed. Results show that due to the low Signal to Noise Ratio (SNR) in WSAN environment, simple modulation schemes with low spectral efficiency have better delay and reliability performance. Otherwise, the delay will be highly sensitive to SNR, packet payload, number of competing nodes.