X-band cavity-backed slot antennas and coupled oscillator systems

In this paper, substrate integrated waveguide (SIW) cavity-backed antennas and coupled oscillator systems are proposed. The cavity-backed structure permits to overcome potential problems such as heat dissipation and unwanted surface wave modes in large array implementations, and may provide better phase noise performances. Moreover, it provides a design parameter to control coupling among the oscillator elements. Full-wave FEM-based and harmonic balance (HB) analyses are used to design passive antennas and active antenna oscillators, whose frequency responses have been evaluated for different values of certain geometrical parameters. Based on the results obtained, different configurations of two-element coupled oscillator antenna systems have been proposed. Compact, single substrate prototypes are presented. These low cost implementations could be useful in radar and communication applications.