Coherence bandwidth in a 1.8-GHz urban mobile radio channel

Results of 1.8-GHz narrow band measurements in an urban area to characterize the coherence bandwidth at 0.9 and 0.5 correlation level are presented. The correlation coefficient between two frequency-spaced envelopes is found to be highly dependent on the receiver position. The confidence interval of the correlation coefficient estimator is calculated to ensure accuracy. For coherence bandwidth, frequency separations less than 60 kHz and 136 kHz will guarantee correlation levels larger than 0.9 and 0.5, respectively, for 90% of the time.