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A comparison is made of the statistical properties of energy density reception of mobile radio signals with those of multichannel predetection combining diversity reception using an array of whip antennas lined up transverse to the direction of motion. Theoretically, the energy density system is about as effective as a 3-channel diversity system in reducing fading. This conclusion was obtained from cumulative distribution function (cdf) curves, level crossing rate curves, and power spectra density function curves. Experimentally, the probability distribution curves show that the variation of the signal amplitude of a 4-channel diversity system is less than that of an energy density signal, but the fading rates of the two signals are almost the same. The experimental power spectra curves verify that the shape of the output spectrum for the diversity receiver is independent of the number of channels, but the level is reduced in magnitude with more channels. The output spectrum for the energy density system is more concentrated at lower frequencies than the diversity receiver.