  For a three-cell constant cellular interfering network, a new property of
alignment is identified, i.e., interference alignment (IA) solution obtained in
an user-cooperation scenario can also be applied in a non-cooperation
environment. By using this property, an algorithm is proposed by jointly
designing transmit and receive beamforming matrices. Analysis and numerical
results show that more degree of freedom (DoF) can be achieved compared with
conventional schemes in most cases.
