that alignment of antennas in a wpan application is relatively easy referring now to fig9 a further antenna 30 u2032 is shown the ground plane 32 u2032 is u201c t shaped u201d to extend to the edge of the substrate 36 to accommodate an extended microstrip feed line 108 u2032 a supporting housing 120 also is shown the housing provides structural integrity for the substrate 36 and can be of metal or plastics material fig1 is a view of the antenna 30 u2032 showing the feed network 100 the elements are shown as wireframe outlines so as to appear transparent the optimal width wgnd of the u2018 leg 33 is determined by a numerical simulation optimisation and for the present embodiment a width of 5 mm is chosen by this arrangement a feed port 110 and ground return path are provided at the edge of the substrate which makes for easy external connection most usually to an integrated circuit which needs to be in close proximity to the antenna additionally the leg 33 of the ground plane prevents the feed line 108 u2032 from radiating the base of the housing omitted in fig1 forms the reflector and therefore needs to be fabricated from a conductive material the array size may also be varied to suit other applications depending upon the gain required by the antenna in the present embodiment of 4 u00d7 2 array elements the required.