A low cost, low side lobe and high efficiency non-orthogonally coupled slotted waveguide array antenna for monopulse radar tracking

Modern airborne tracking radar systems require antennas which are rugged and have high electrical performance. The paper deals with a novel design and manufacturing technique for a non-orthogonally coupled resonant slotted waveguide array antenna for monopulse tracking radar. Critical design, manufacturing and mass producibility issues have been considered, leading to a successful realization of a low profile, diagonally coupled slotted waveguide monopulse array antenna. For the foundation of high frequency applications, this paper demonstrates the excellent performance of these types of antennas designed for 17 GHz.. The design has two original and innovative features. The first is the diagonal quadrant division of the radiating aperture and use of non-orthogonal slot coupler to couple the power from the monopulse comparator output ports to the array feed input ports. Secondly, novel machining and joining processes have been introduced for manufacturing this antenna, resulting in cost effective cent per cent yield (zero defect units). Using this technology, several accurate, frequency independent choices can be analysed and studied with ease at cheaper cost before cutting metal.