Carrier frequency effects on propagation characteristics in rural macro environments

Based on the experimental results obtained from the extensive wideband MIMO channel measurements at 2.38, 3.705 and 5.25 GHz in Line-Of-Sight (LOS) rural macro environments, the empirical Path Loss (PL) model is proposed for the IMT-Advanced systems. PL exponent, intercept, frequency dependent factor and standard deviation of Shadow Fading (SF) are obtained by using the Least Square (LS) method. It is found that the frequency dependent factor well reflects the measured PL at each carrier frequency. We investigate the frequency dependence of SF and also propose an autocorrelation function which can be modeled with Exponentially Decaying Wave (EDW) function. It is observed that the EDW function well represent the general characteristic of autocorrelation curves.