ABSTRACT
Antennas have a decisive influence on the performance of wireless communication systems: depending on radiation characteristics, antennas differently affect cell coverage, multipath discrimination, and cochannel interference, which directly or indirectly impact on system performance. Antenna beam shaping is a simple strategy to act on these parameters in a controlled way. More sophisticated solutions like adaptive antennas may be considered with the same objective, but these antennas tend to be less affordable at millimeter waves, and more complex. Two main approaches may be used for beam shaping: antenna arrays or shaped-aperture antennas. Printed arrays are compact and very flexible for beam shaping. The most simple beam-shaping requirements for wireless communications are found in lower frequency applications, related with the need for sectored coverage of base station antennas, or with the requirement for low radiation of the mobile terminal antenna in the direction of the user head.
