A radio frequency, RF, antenna array comprising: a reflector element; a first antenna unit configured to operate at a first frequency band and including three antenna elements (118, 120, 122) that are collocated on the reflector element, each of the three antenna elements (118, 120, 122) having a different polarization direction than the other two antenna elements of the first antenna unit; a first switch associated with the first antenna unit and a first conductive line configured to selectively connect each one of the antenna elements (118, 120, 122) of the first antenna unit to the first conductive line; a second antenna unit configured to operate at a second frequency band and including three antenna elements (124, 126, 130) that are collocated on the reflector element, each of the three antenna elements (124, 126, 130) having a different polarization direction than the other two antenna elements of the second antenna unit; and a second switch associated with the second antenna unit and a second conductive line configured to selectively connect each one of the antenna elements (124, 126, 130) of the second antenna unit to the second conductive line; wherein the antenna array further comprises: a plurality of the first antenna units, and a plurality of the first switches, each of the first switches being associated with a respective one of the first antenna units and a respective first conductive line; and a plurality of the second antenna units, and a plurality of the second switches, each of the second switches being associated with a respective one of the second antenna units and a respective second conductive line; wherein each of the three antenna elements (118, 120, 122, 124, 126, 130) in each of the first and second antenna units (110, 112) has a polarization direction for emitting or receiving RF signals that is orthogonal to a polarization direction of the other two antenna elements; and wherein at least some of the first antenna units have different polarization orientations on the reflector element than at least some of the other first antenna units. a reflector element; a first antenna unit configured to operate at a first frequency band and including three antenna elements (118, 120, 122) that are collocated on the reflector element, each of the three antenna elements (118, 120, 122) having a different polarization direction than the other two antenna elements of the first antenna unit; a first switch associated with the first antenna unit and a first conductive line configured to selectively connect each one of the antenna elements (118, 120, 122) of the first antenna unit to the first conductive line; a second antenna unit configured to operate at a second frequency band and including three antenna elements (124, 126, 130) that are collocated on the reflector element, each of the three antenna elements (124, 126, 130) having a different polarization direction than the other two antenna elements of the second antenna unit; and a second switch associated with the second antenna unit and a second conductive line configured to selectively connect each one of the antenna elements (124, 126, 130) of the second antenna unit to the second conductive line; wherein the antenna array further comprises: a plurality of the first antenna units, and a plurality of the first switches, each of the first switches being associated with a respective one of the first antenna units and a respective first conductive line; and a plurality of the second antenna units, and a plurality of the second switches, each of the second switches being associated with a respective one of the second antenna units and a respective second conductive line; wherein each of the three antenna elements (118, 120, 122, 124, 126, 130) in each of the first and second antenna units (110, 112) has a polarization direction for emitting or receiving RF signals that is orthogonal to a polarization direction of the other two antenna elements; and wherein at least some of the first antenna units have different polarization orientations on the reflector element than at least some of the other first antenna units. a plurality of the first antenna units, and a plurality of the first switches, each of the first switches being associated with a respective one of the first antenna units and a respective first conductive line; and a plurality of the second antenna units, and a plurality of the second switches, each of the second switches being associated with a respective one of the second antenna units and a respective second conductive line; wherein each of the three antenna elements (118, 120, 122, 124, 126, 130) in each of the first and second antenna units (110, 112) has a polarization direction for emitting or receiving RF signals that is orthogonal to a polarization direction of the other two antenna elements; and wherein at least some of the first antenna units have different polarization orientations on the reflector element than at least some of the other first antenna units.