  We analyze the mean and the variance of the useful signal and interference
powers in a multi-cell network using zero-forcing beamforming (ZF-BF) with two
beamformer normalization approaches. While the mean has been the main focus in
earlier studies on ZF-BF, analysis of the variance has not been tackled. Our
analysis provides a complete statistical study, sheds light on the importance
of the variance by deriving closed-form expressions for the signals' two
moments, and provides a practical use for these expressions; we use the gamma
or lognormal distribution for the interference power to analytically calculate
the outage.
