Comparison of antenna beam broadening methods for phased array radar applications

Multifunction phased array radars usually have narrow beam widths to meet their tracking requirements such as resolution and accuracy. Search of a large area by this narrow beam becomes too time consuming. In these occasions antenna beam broadening is useful and may reduce search time or increase probability of detection. In this paper different methods for antenna beam broadening is discussed and compared with each other. A broad beam is designed with each of the phase only, amplitude only and amplitude-phase methods. Phase only method shows better power efficiency but amplitude only method yields better side lobe level and ripples. It is shown that, for special broadening factors, beam broadening may lead to a better coverage and power efficiency than narrow beam antenna and is better suited for phased array radar applications.