Research On 400MHz Wireless Domain Network Channel Modeling Based On Markov Chain

The rapid development of wireless communication in recent years has been widely used in WLAN, Bluetooth, ZigBee, Wireless HD and other short-range wireless communication technologies. It indicates that the human body-centered LAN will develop more rapidly. Meanwhile, as the world’s aging population is getting more and more serious, the wireless applications in the human body-centered healthcare will also become more widespread. In order to fully understand the wireless network around the human body, many research scholars have been devoted to the study of Wireless Body Area Network (WBAN). Since the propagation channel of WBAN is more complex and changeable than the traditional channel, research on the propagation channel of WBAN is a difficult and hot spot.Firstly, In this paper, a mobile and portable channel testing system is developed. Realization of this system includes the construction of the hardware platform and the design of the software program. Among, The part of hardware is use of the Chengdu wireless dragon’s C51RF-PS development board. The key parts of software realization contain point wireless communication, power acquisition of the received signal, implementation of the data transfer rate, and so on. Testing results show that the system has very strong stability, and it can successfully send and receive data in the case of various human activities. Moreover, the system can acquire the RSSI (Received Signal Strength Indicator) value of the signal received power, and the signal sampling rate of the test system can reach250kbps.Subsequently,this paper utilizes the development system, which is under the on-bod y and off-body communication modes, to test the WABM channel of different environ ments and actions, and obtains a number of test data, and presents the drawing of differ ent sets of test data, and analyses the difference between data.In the end, this paper proposed a two-state Markov channel model for the indoor environment (such as hospital). The channel environment is divided into ideal and non ideal states, and we assume that the ideal state is Rice model and the non ideal state is Rayleign model. Based on the data obtained from the test system, the two state Markov model is applied to the indoor channel modeling in the hospital. By comparing the first-order feature of the simulated data with the measured data, we find that two CDF curves agree well. Hence, the applicability of the model is verified.