Design of a Miniature Ku-Band Monopulse Waveguide Slotted Array Antenna

Slotted waveguide array antennas find wide applications in many microwave and radar systems requiring narrow beam and low side lobe level. Light weight, geometric simplicity, high power, limited scan volume and reliability make waveguide slotted arrays very useful for airborne radar application. A Miniature Ku-Band monopulse slotted waveguide array antenna in quarter height waveguide configuration for on-board radar application is presented. Antenna consists of five layers including monopulse comparator. All the layers of the antenna have been designed and analyzed using CST Microwave Studio. Taylor's aperture distribution is selected to obtain narrow beam with low sidelobes. This paper describes design, fabrication technique and electrical performance study to produce desired radiation pattern. The gain of the sum pattern is better than 23 dB while the side lobe level is -21dB in H-plane and -14dB in E-plane. The crossover of difference channels in both planes are around 3.8dB and the null depth in H-plane is 36dB and in E-plane is 25dB.