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The propagation characteristics of radio wave have been an important topic in wireless communications. Based on the ray tracing method, the propagation of radio wave for indoor NLOS environment is simulated and analyzed. In this paper, the received power is obtained by simulation, and we will analyze the impact of various factors on the received power. Later, the study can be used to simplify indoor radio wave propagation model and provide a theoretical basis, which is in favor of indoor wireless communication network planning and optimization and can lay the foundation of the development of future technology.

The propagation characteristics of radio wave have been an important topic in wireless communications. The traditional models are mostly for the macro-cell environment, which uses a statistical method according to mass of actual measurement data. With the micro-cell and pico-cell system starting to be used, the traditional statistical methods have failed. Method of Moment [

Beginning in the 1990s, with the computing capability significantly improving, the deterministic models have become the main indoor prediction model, due to its high-precision prediction effect. Existing deterministic models are iterative equation invariance test method (MEI) [

In this paper, the simulation is placed in the indoor community environment, in which there are a number of wooden shelve. The size of the supermarket is

In the simulation, the transmitting antenna is location in (1.3, 3.5, 4.0), which is vertical polarization. The transmitting power is 33 dBm and the gain of the antenna is 5 dBi. Besides, the operating frequency is 2.0 GHz. The receiving antenna moves respectively along the four path AB, CD, EF and DF, as shown in

Firstly, we neglect the object indoor, and respectively simulate AB, CD, EF, DF, shown in

Line AB starts at point A(3.0, 3.5, 1.7) and ends at point B(12.5, 3.5, 1.7), which has 0.5 m intervals along the x-axis linear path. As a general reception, the height of receiving antenna is 1.7m. Line DF starts at point D(5.2, 6.7, 1.7) and ends at point F(10, 6.7, 1.7). Like line AB, line DF has 0.5 m intervals along the x-axis linear path. The receiving power of the two paths in the simulation are shown in

Line CD starts at point C(5.2, 0.4, 1.7) and ends at point D(5.2, 6.7, 1.7), which has 0.5 m intervals along the y-axis linear path. Line EF starts at point E(10, 0.4, 1.7) and ends at point D(10, 6.7, 1.7). Like line CD, line DF has 0.5 m intervals along the y-axis linear path. The receiving power of the two paths in the simulation are shown in

In the actual scene, radio wave is shadowed seriously, so the impact of objects for indoor radio propagation can’t be ignored. There are no direct rays in the blocked area, but a myriad of reflection, transmission, diffraction and even diffuse rays can still reach there. Below, we can consider the following indoor scenario shown in

According to the complexity of the simulation, the indoor environment of the simulation calculation can be divided into two groups: one group was predicted in the empty room, which is an ideal situation; another group is in a typical indoor environment, and the results were compared to the same path. According to the Simulation results of the two groups, we can conclude as follows:

1) In

2) It can be seen from the simulation results that the received power can rapidly change 10 - 20 dBm. The fast fading is due to multipath propagation of radio wave.

3) With the line of sight propagation, the value of the result is large, which is the performance of Rician fading. For visual path AB, which considers indoor objects, will increase 20 dBm. Because it doesn’t have the direct ray path indoor, and it generates a lot of reflection and diffracted rays.

4) In the absence of line of sight ray or only existing higher-order reflected rays, the value of the result is small, which is the performance of Rayleigh fading.

As can be seen from

This work has been supported by the National Natural Science Fund under Grant no. 61372045 and by the Ministry of International Journal of Antennas; Propagation and Education of Higher Specialized Research Fund for the Doctoral Program under Grant no. 20123223120003.

Feng Chen,Yuanjian Liu,Pengfei Wang, (2015) Study on the Propagation Characteristics of Radio Wave for Indoor Non-Line-of-Sight. Journal of Computer and Communications,03,40-43. doi: 10.4236/jcc.2015.33007