Correlation analysis of multiple-input multiple-output channels with cross-polarized antennas

In this paper, we investigate the correlation characteristics of the multiple-input multiple-output (MIMO) channels based on the outdoor measurement. The correlation coefficients for both co-polarized and cross-polarized channels are studied. Results show that the polarization decorrelation performs better than spatial decorrelation in strong line of sight (LOS) scenario. In non line of sight (NLOS) scenario, they are of the same order. The envelope correlation coefficient is observed to be approximately the same as the power correlation coefficient in both time and frequency domain. The correlation of the channels highly depends on the propagation scenarios, and it increases as the Ricean K factor increases. It is also found that the correlation in the elevation domain is much higher than that in the azimuth domain.