Ultra wideband indoor channel modeling for personal area networking

This paper investigates the Line of Sight (LOS) path loss characteristics of the UWB channel by explicitly focusing on a very short range of 1¿5 m. A vector network analyzer was used to measure the channel transfer function in the frequency band of 6¿8 GHz. It has been observed that the published path loss models for UWB communications report a path loss exponent in the vicinity of the benchmark `2¿ for LOS indoor measurements for 1¿10 m. However, as one of the potential applications of UWB technology will be for wireless desktop environments, it becomes imperative to characterize the UWB channel for the same. We find that though the overall value of the path loss exponent for 1¿5 m is 1.85, which is in agreement with the previously reported values, for 1¿2 m, 2¿3 m, 3¿4 m and 4¿5 m it is found to be 1.55, 1.97, 1.98 and 3.35 respectively. This distance dependent path loss modeling reveals that beyond 4 m channel characteristics change considerably. Therefore, a path loss exponent of value less than 2 is well suitable for desktop applications preferably within a range of 4 m.