The invention concerns an array of radiating elements. A first plurality of antenna elements in a first plane in an array configuration is configured for operating on a first band of frequencies. A second plurality of planar antenna elements in an array configuration is configured for operating on a second frequency band, the second plurality of antenna elements is also positioned in the first plane. A first effective ground plane is provided for the first plurality of antenna elements and a second effective ground plane is provided for the second plurality of antenna elements. A first spacing between the first plurality of elements and the first effective ground plane is different from a second spacing between the second plurality of elements and the second effective ground plane. According to one embodiment, the second plurality of elements are adjacent to one another in a unitary cluster that is disposed within the first plurality of elements.