Gregg E. Rasor

Pseudo-pilot OFDM scheme for 802.11a and R/A in DSRC applications

A pseudo-pilot scheme is proposed for 802.11a and 802.11R/A (roadside applications version) in DSRC (dedicated short range communication) applications. The scheme overcomes the shortcomings of the original IEEE 802.11a standard by substituting pilots in selected data slots for channel equalization; at the receiver, the pilots are removed and random data inserted. It is shown that the technique is very effective in addressing the high mobility DSRC environment with minor changes to the 802.11a and R/A physical layer.

Composite antenna pattern for realistic ray tracing simulations

The widespread adoption of wireless local area networks (WLAN) and the emerging wireless personal area networks (WPAN) has required a deeper understanding of the indoor propagation channel. As a consequence, ray analysis techniques based on geometrical optics have emerged as the tools of choice for modeling indoor and outdoor environments. In realistic scenarios, antennas will be installed within proximity to wall structures or embedded in complex environments such as vehicle interiors for telematics applications. Hence. we no longer have free space antenna patterns but composite antenna patterns. We consider here the application of the finite-difference time-domain (FDTD) technique for obtaining 3D antenna patterns in complex structures with different material properties. Simulation results are submitted and discussed.