Summary
International Symposium on Antennas and Propagation
2012
Session Number:POS1
Session:
Number:POS1-26
Mean Effective Gain Calculation in Realistic Environments based on Ray-tracing
Hyung-ju Kim,
pp.-
Publication Date:2012/10/29
Online ISSN:2188-5079
Summary:
In the mobile communications environment, multipath fading occurs due to reflections, diffractions, and scatterings caused by surrounding buildings and geographical elements. These environmental features are the main reasons of poor transceiving performance. The antenna gain is one of the key parameters in the evaluation of antenna performance together with radiation pattern, impedance, and sensitivity. But antenna gain measurement in conventional anechoic chamber cannot give full credit to the actual mobile communication environment. This is because the anechoic chamber cannot accommodate the real environment for mobile terminal operation. Thus antenna gains measured in anechoic chamber and real environment are different to each other in its character. MEG (Mean Effective Gain) is the antenna gain that concerns the surrounding environment of the receiving antenna and is different from the conventional one measured in free space. With calculated and measured MEG, one can figure out how well the receiving antenna could be fit to the surrounding environment and offers a full understanding on the interaction between the antenna and its surroundings. To calculate the MEG, an angular density function (which represents distribution of transmitted wave that has reached the receiving antenna) should be defined first. In previous studies, various statistical models have been chosen to represent the angular density function such as Gaussian distribution or Laplacian distribution. But with these models, it is difficult to define precise angular density function of the transmitted wave, so it is hard to reflect the effect of surrounding environment in MEG calculation. In this paper, DRT (Deterministic Ray-Tube) method, which is one of the ray tracing methods based on image concept, has been used to find all the wave paths from a transmitting station to a receiving station and by using these transmitted wave distributions in MEG calculation, the effect of surrounding environment can be analysed accurately.