An antenna structure (10) includes a plurality of transmit linear elements (22a-22d) arranged parallel to one another and a plurality of receive linear elements (24a-24d) also arranged parallel to one another. Individual ones of the plurality of transmit elements are spaced apart from one another and have one of the plurality of receive elements disposed therebetween. A width of each of the plurality of transmit elements and the plurality of receive elements varies periodically along a length of the element thus periodically modulating each element. A narrowest width portion of a transmit element is disposed adjacent to a widest width portion of an adjacently disposed receive element, and vice versa, minimizing coupling between the elements. Transmit amplifiers (16a, 16b) and receive amplifiers (30a, 30b) are located at opposite ends of an antenna stalk body (36) where the transmit amplifiers and receive amplifiers are intimately associated with their respective antenna elements, minimizing losses.