Recent advancements in the area of integrated circuits has lead to the development of various miniaturized sensors and actuators that could be easily used as body sensors by the aged group of population or patients suffering from chronic diseases. Variations in the physiological parameters of human body such as heart beat, body temperature, Electro Cardio Graphy (ECG) etc or any other chronic disorders could be monitored continuously in order to manage the health conditions. The lower most layers of WBAN architecture are Physical and Medium Access layers. The performance of Wireless Body Area Network (WBAN) solely depends on the parameter of these layers. Implementation of these sensors and actuators in, on or around the human body leads to the development of WBAN. IEEE 802.15.6 emerged as one of the standards for WBAN. The analysis of one of the parameters of the physical layer namely, Bit Error Rate (BER) for different types of channel modeling is used to decide the performance of WBAN in its physical layer. Also analysis of path loss for log normal channel model is carried out for an Ultra Wide Band signals.