Wide-beam microstrip antenna for application in 24 GHz short-range Doppler sensors

A wide-beam microstrip antenna for applications in short-range Doppler sensors has been developed. Beam widening has been achieved with the use of appropriately fed three radiating patches. To ensure a proper signal distribution along the array, a center radiating element has been designed as an aperture coupled patch fed at its center thorough the slot. Moreover, the center patch serves as a two-way power divider allowing for feeding two outer patches with appropriate amplitudes and phases ensuring simultaneously central symmetry of the antenna which improves radiation pattern.