Effect of random alignment sway on the performance of IrDA handheld devices

We present the results from a performance simulation of an IrDA based infrared wireless link involving a handheld portable device in which there is a random variation of angular alignment due to natural directional hand `sway´ of the device operator. The variation in transmitter angle can affect the link bit-error-rate (BER) by going out of alignment with the receiver, thus affecting the link throughput and file transfer delay due to the requirement of retransmissions at the data link layer of the IrDA protocol if data packets are lost. Results are produced from a simulation model of the IrDA protocol using the OPNET^TM package, with physical layer properties based on an analytical model of the link topology, and an angular sway model based on a Gaussian distribution of angular positions