Embodiments of the present invention disclose a signal processing method and a base station. The method may include: performing, by a base station, packet assembly, code modulation, and multi-antenna processing on downlink channel data, so as to form antenna port signals. The method may also include performing, by the base station, orthogonal transform on the antenna port signals according to a preset matrix used for orthogonal transform, and simultaneously sending, by the base station, orthogonally transformed antenna port signals to user equipment by using different antennas, where cells covered by the different antennas have a same cell identity.