An antenna array comprising: a first and second plurality of unit cells respectively connected in series via respective transmission lines , each of the unit cells including a microstrip patch having two insets on a first axis of the microstrip patch , the microstrip patch being connected to a first and a second of the transmission lines at the two insets , respectively; a first and second termination unit cell each connected in series to a corresponding one unit cell of the first and second plurality of unit cells via one of the transmission lines , each termination unit cell including a microstrip patch having an inset on a second axis of the microstrip patch , the microstrip patch being connected to the one transmission line at the inset ; the antenna array further comprising a first sub-array comprising the first plurality of unit cells and the first termination unit cell in a forward in-phase feed, a second sub-array comprising the second plurality of unit cells and the second termination unit cell in a backwards, out-of-phase feed, wherein the first sub-array and the second sub-array provide differential feeding to each unit cell of the first plurality of unit cells and the second plurality of unit cells via the first and second transmission lines , wherein the second plurality of unit cells are provided in a staggered arrangement at an offset relative to the first plurality of unit cells , wherein the microstrip patch of each of the unit cells further has a third inset and a fourth inset , the microstrip patch being connected to third and fourth transmission lines at the third inset and the fourth inset , respectively, whereas the third inset and the fourth inset are disposed on a third axis perpendicular to the first axis , and wherein the first plurality of unit cells is arranged linearly on a fourth axis parallel to a fifth axis on which there is linearly arranged the second plurality of the unit cells . a first and second plurality of unit cells respectively connected in series via respective transmission lines , each of the unit cells including a microstrip patch having two insets on a first axis of the microstrip patch , the microstrip patch being connected to a first and a second of the transmission lines at the two insets , respectively; a first and second termination unit cell each connected in series to a corresponding one unit cell of the first and second plurality of unit cells via one of the transmission lines , each termination unit cell including a microstrip patch having an inset on a second axis of the microstrip patch , the microstrip patch being connected to the one transmission line at the inset ; the antenna array further comprising a first sub-array comprising the first plurality of unit cells and the first termination unit cell in a forward in-phase feed, a second sub-array comprising the second plurality of unit cells and the second termination unit cell in a backwards, out-of-phase feed, wherein the first sub-array and the second sub-array provide differential feeding to each unit cell of the first plurality of unit cells and the second plurality of unit cells via the first and second transmission lines , wherein the second plurality of unit cells are provided in a staggered arrangement at an offset relative to the first plurality of unit cells , wherein the microstrip patch of each of the unit cells further has a third inset and a fourth inset , the microstrip patch being connected to third and fourth transmission lines at the third inset and the fourth inset , respectively, whereas the third inset and the fourth inset are disposed on a third axis perpendicular to the first axis , and wherein the first plurality of unit cells is arranged linearly on a fourth axis parallel to a fifth axis on which there is linearly arranged the second plurality of the unit cells . <EOS>