Steered coupled-cavity-backed Hertzian dipole array

This paper presents the operating characteristics of a coupled-cavity-backed Hertzian dipole resonator array excited with mutually injection-locked voltage-controlled oscillators (VCOs). It is demonstrated that microwave spatial power-combined inter-injection locking through mutual coupling of individual antenna oscillators can be obtained with an auxiliary coupling network formed by a cavity iris configuration introduced within a reduced-height waveguide arrangement. As a result, strong mutual-coupling control can be realized and exploited in conjunction with self-injection-locked oscillators in order to achieve direct phase modulation of the locked oscillators. Beam scanning up to 10° off the broadside through locked VCO phase modification has been demonstrated in a three-element array occupying a space of only 0.6 λ₀×0.027 λ_o at 998 MHz