Generation of difference pattern from a linear microstrip patch array for the monopulse radar application

This paper presents a new technique to generate difference pattern from a circularly polarized (CP) microstrip array antenna for monopulse radar application. The individual truncated corner radiators of the array are left‐handed CP (LHCP). The difference pattern is generated by placing together the left and right side proposed single elements in opposite direction to each other along the y‐axis with an inter‐element spacing of 3 λ /4 . In order to achieve a stable radiation pattern with low sidelobe level over a resonating band, a uniform feed network is designed for the array. Finally, the proposed single element and the 4 × 1 array are designed, fabricated, and measured. The left‐polarized element of the array structure, resonates at 5.90 GHz with good circular polarization properties. The array prototype resonates at 5.904 GHz with 3.60% impedance bandwidth. The array gives null depth greater than −30 dB at θ = 0 ∘ in different ϕ cuts. The proposed left‐CP array has a gain of 9.48 dBic and a radiation efficiency of 77.50% . Moreover, the measured results matched well with the simulated results, which proves the effectiveness of the proposed approach for practical application.