Experimental evaluation of UWB transmission waveform for short-range wireless networks

In this paper, UWB transmission waveform is modeled by using multi-ray technique. There are three case studies. The first case concerns only the normal direct path. The second one considers two rays that consist of the direct and ground reflection path. And the last case considers the direct, ground and ceiling reflection path. These cases are used to approximately model the UWB channel in the anechoic chamber, outdoor and indoor environment, respectively. The transmitted and received antenna use the trapezoidal antenna and perform the same characteristics. The impulse responses of these antenna at each specific pointing angle are calculated by using FDTD transformation method to the far field region that are shown. The channel of this experiment is the free space and applies in the Friis´ transmission formula. The UWB channel impulse responses of each case are illustrated. After that, the transmitted signal is set to be a modulated Gaussian pulse within frequency ranges between 3.1 GHz and 10.6 GHz. The matched filter reception is considered to maximize the SNR at the receiver for the evaluation. The received signal of each UWB model are shown. The effects of each UWB channel are described from the results.