Performance evaluation results of the Infrared Data Association (IrDA) Advanced Infrared Medium Access Control (AIr MAC) layer are presented. AIr MAC implements Unreserved and Reserved data transfer modes. Reserved mode employs the Request To Send / Clear To Send (RTS/CTS) media access reservation scheme. A simulator for the AIr MAC layer is developed. The importance of the Collision Avoidance ...

Several pin configurations were tested in an attempt to improve the aero-optical environment at large look-back angles over a cylindrical turret with a flat window. When small-diameter, tall pins were placed upstream of the cylindrical turret they created a partial blockage and formed a second shear layer. The second shear layer reduced the turbulent intensity of the main shear layer, with a re...

An Acoustic Window is comprised of a horizontal sliding window at the inner layer, and side-hung window, which can be pushed to open, on one side outer fixed glazing other side. The serves as “baffle” for screening off noise passing through opened when it slid behind window. This baffle-type acoustic proved reduce up 8 dB(A) road traffic gaining popularity in residential developments Hong Kong,...

We investigate a cross layer congestion control technique for TCP Reno-2 (NewReno) in CDMA-based wireless ad-hoc networks in which both TCP layer and PHY layer jointly control congestion. The PHY layer varies transmission power based on the channel condition, interference power received and congestion in the network and seeks to transmit at a minimum power level, whereas the TCP layer controls ...

The IEEE 802.11 MAC standard for wireless ad hoc networks adopts Binary Exponential Back-off (BEB) mechanism to resolve bandwidth contention between stations. BEB mechanism controls the bandwidth allocation for each station by choosing a back-off value from one to CW according to the uniform random distribution, where CW is the contention window size. However, in asymmetric multi-hop networks, ...