Spatial diversity

Antenna techniques

• Spatial diversity employs multiple antennas, usually with the same characteristics, that are physically separated from one another. Depending upon the expected incidence of the incoming signal, sometimes a space on the order of a wavelength is sufficient. Other times much larger distances are needed.
  • Macrodiversity is when transmitters are spaced much longer than the wavelength. When the spacing is of the same order or smaller than the wavelength, it is called microdiversity.
  • Cellularization or sectorization, for example, is a spatial diversity scheme that can have antennas or base stations miles apart. This is especially beneficial for the mobile communication industry since it allows multiple users to share a limited communication spectrum and avoid co-channel interference.